V. Nabokov.
Notes on the Morphology of the Genus Lycæides (Lycænidæ, Lepidoptera).
Psyche 51:104-138, 1944.

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Psyche [Sept.-Dec.
NOTES ON THE MORPHOLOGY OF THE
GENUS LYCBIDES
(LYCLENIDB, LEPIDOPTERA)
Out of the hundred or so holarctic Lycsenids distributed among at least sixteen genera of the subfamily Plebejince (defi- nitely fixed by Stempffer, 193 7, Bull. soc. ent. France 42 : 2 11, etc.; not covering the superficial concept of "Blues" for which no systematic term or division can exist), only fourteen species or so, two of which are obvious invaders from the Tropics, occur in the nearctic region (north of the 30th parallel). These be- long to seven genera, four of which (the first four in the list given below) are holarctic and contain together six species of which one half is common to both regions. All three exclusively American genera have the free portion of the sedeagus elon- gated; all the exclusively palearctic genera, except Aricia R. L. (and the, mainly tropical, Chilades Moore and Freyeria Cour- voisier) have stubby or proximally "bulbous" free portions. Of the four genera common to both regions one half belongs to the first type and one half to the second.
The only Plebejince, so far known to exist in the nearctic re- gion, are: 1. Agriades Hubner : glandon Prunner (holarctic) ; 2. Vacciniina Tutt: optilete Knoch (holarctic); 3. Lycceides Hubner : argyrognomon Bergstrasser (holarctic) , scudderi Ed- wards, melissa Edwards; 4. Plebejus Kluk: scepiolus Boisdu- val; 5. Plebulina, n.g. (remarkably amalgamating the Plebejus or Lycceides sedeagus with the valval processus superior and uncus + falces of Albulina Tutt): emigdionis Grinnell (geno- type) ; 6. Icaricia, n.g. (allied to Aricia R.L. in sedeagus; some- what to Polyommatus Latreille in general type of uncus as seen ventrally; close to both in processus superior of valve; dis- tinguishable by the underdeveloped, i.e. devoid distally of any Published with the aid of a grant from the Museum of Comparative Zoiilogy at Harvard College.
Unexpectedly represented by speciosa Staudinger in the Andes.



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19441 Genus Lycceides 105
semblance of hook, triangular, laminate, proximally very broad falx, its very gradually tapering apex hardly exceeding in height the level of its strongly humped humerulus) : icarioides Boisdu- val (genotype) with its various subspecies (clamoring for a reviser) and four other species, viz.: demon Doubleday-Hewit- son, spt indeterm. (? chlorine, Skinner), neurona Skinner and shastu Edwards; these four structurally smaller than the geno- type (with an uncus lobe distally somewhat grooved in lateral view but not actually revealing Sternpffer's process as it occurs in Arich anteros Freyer), and 7. Hem.iargus Hiibner: a curi- ously aberrant genus (somewhat allied to Chilades Moore) which is represented by hanno Stoll and in which I very provi- sionally retain isoh Reakirt. An unexpected fdtura superior is present in the former and is monstrously developed in the latter.
For some time I have been especially concerned with the genus Lycosides. In a preliminary paper (Nabokov, 1943 [March, 19441, Psyche 50 :87 etc.) an attempt was made to clear up several taxonomic points mainly in regard to the ne- arctic section; the palearctic one is still badly confused taxo- nomically, especially because the type specimens of a number of races have never been examined structurally (German au- thors, for instance, blindly relying upon the haphazard commer- cial identifications of the Staudinger firm). These matters I shall discuss elsewhere, but it is necessary to make a" few com- ments regarding the genotype.
This is the "argus Linn." of Hiibner ( [ 182 3 1, Verz. bekannt. Schmett. 5 :69), nec Linn., which was selected as the type by Scudder (1872, 4th Ann. Rep. Peabody Acad. Sci. 1871:54; 1875, Roc. Amer. Acad. Arts Sci., Boston 10:208), and since Hiibner's argus is the "Argus" of Reverdin (1917, in Oberthur, Et. lbp. comp. 14: 2 2, fig. 3, uncus) it follows that it is also the "argyrognomon Bergstrasser" of Tutt [and Chapman] (1909, Brit. Butt. 3:205-208, pi. 50, fig. 2, uncus) and thus not the "Ligurka?' of Reverdin (191 7, op. cit.: 22, fig. 4, uncus) which is the ''ismenias Meigen" of Heydemann (1931, Int. ent. Zft. 25: 129) and the^wgyrognomon Bergstrasser" of Forster (1938, 'With an incidental suggestion (LC. : 88, not4 that cleobis Bremer falls to mbsohnus Eversmann. I now find that Hemming (1938, Froc. R. Ent. Soc. London, 7 (I), B : 5-7, fig., mate, type) had already come to the same conclusion.



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106 Psyche [Sept-Dec.
Mitt. Munchner ent. ges. 28: 1 1 ) , wrongly, and belatedly, se- lected by the latter author as "type" with thfe suggestion that readers look up for themselves Hiibner's plate. They do, and find (Hiibner, Samml. europ. Schmett. pi. 64 [1800]) that fig. 316, to which Scudder referred when selecting the type, can be easily matched by German maim of the "Argus" of Reverdin and of the "argyrognomm Bergstr." of Tutt and, consequently, of Hemming (1934, Gen. names hoi. butt. 1: 1081, who defi- nitely fixed it (thus excluding the other species of Lycazides which he knew well) as the type of the genus, and this clinches the matter, whatever the two species be called. The publication of Beuret's important paper ( 1935, Lambillonea 35: 162, etc.) has led to attempts to transfer the name argyrognomon Berg- strasser (1 779, Nomenclatur, 2: 76-77, pi. 46, fig. 1,2) from the short-falx species (the genotype) to which it was applied by Tutt (1909) and which we shall term for the moment species X, to the long-falx species, ismenks Meigen, 1830 (Heyde- mann? 193 1) which we shall term species Y. These attempts have been prompted by the fact that female specimens appar- ently belonging to Y (Beuret, LC., does not give the reasons for his determination), casually collected in the type locality of argyrognomon Bergstr,, proved to be closer to Bergstrasser's equivocal figures than sympatric females of X. One cannot deny that the figures apply better to the general run of Y fe- males than to the general run of X females; but pending further investigation, or some formal decision on the part'of a special commission, I am compelled to use in this paper the name weyrognomun Bergstr, for X because of the following consid- erations: 1. As noted and illustrated by Beuret himself (1934, Lambillonea 34: 119) at a time when he still called X by the name argyrognomw, absolute similarity to Bergstrkser's fig- ures is exhibited by what he (inconsequently) named argyro- gnomon rauraca Beuret (I.c. pi. 5, 5a, fig. 9, 10. See also Beuret, 1928, Soc. Ent. 43, fig. 5, 10, uncus, argyrognomun, 'Augst") . This, now extinct, colony was discovered on a plot of ground, a thousand feet long and 1/6 of this broad, near Augst in the Aargau, N. Switzerland, Le., some 200 miles south from the type locality (BruchkGbel Forest, in the Hesse-Nassau dis- trict, Central Germany) of argyrogwmon Bergstr.; but mor- 'Whose clumsy fixation I reluctantly adopt.



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19441 Genus Lyceeides 107
phologicaUy, i.e., apart from current geographic obsessions and notwithstanding the inconvenience of the thing not flying where it ought to fly, rawaca Beuret was when discovered, and in my opinion remains so BOW, an absolute synonym of orgyro- gnomon argyrogmon Bergstr., since in genitalia it corresponds to Tutt's argyrognomon Bergstr, and in the appearance of the female to Bergstrbser's figures; 2. There is no guarantee that the next German, or British, collector in the Hesse-Nassau dis- trict will not come across chance specimens or a little colony of X, different from the race of X (lyctdasOtdes Beuret, 1934), assigned to the general region, and similar to Beuret's Aargau series-in which case the whole question would have to be brought up again (Tutt remaining the first reviser 5, ; and 3. It is not at all clear what name should be used for X if "argyro- gnomon" is switched to Y. The name acreon Fabricius (1787 Mantissa 2: 76), on the basis of a worn specimen of argus auct (which combined at least X and Y) in the Banksian collection was assigned to the latter omnibus species by Butler (1869, Cat. Diurn. Lep., descr. by Fabricius, in coll. B.M.: 17 1 ) which leaves us none the wiser, even if Butler did see "the type female in Copenhagen" as stated by Heydemann (1931, Int. ent. Zft. 25: 150) who anyway had not seen it himself and thus was per- f &tly unjustified in using the name (I.c. pi. 1, fig. 4, 12) for a race of X. The name' caltiofis Boisduval ( [ 18321 1c. hist. It$. Europe 1 : 58, fig. 4,s) suggested by Hemming (1938, Proc. R. Ent. Soc. London 7,B:4) also cannot be used for X, until the female type (from Grenoble, France) and the Uriage male as- signed to calliopsis by Oberthur (1896, Et. ent. 20, pi. 5, fig. 64) are critically investigated in the B.M. collection. In view of the fantastic misadventures which names have undergone in this genus, pedantic care must be taken, so as to avoid some new nomenclatorial trouble in the future.
The genus Lyccsides, of which argymgnomon Bergstr.-Tutt is the type, is characterized by an uncus (including the fakes) exceedingly different from the corresponding structure found in other subdivisions of the Ptebem, and as I think it advisable to base specific unities upon the intrageneric variation of that character which intergenerically is responsible for the greatest uIn the sense that by figuring the male genitalia he first applied the name argyrognomon Bergstr. (which previously to 1909 had covered at least two Lyeceides species and a form of Plebe* argus Linn.) to a definite species.



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108 Psyche [Sept.-Dec.
hiatus, it is the uncus that I have selected (partly in develop- ment of Reverdin's, Chapman's, and Sterppffer's views) for differentiating species in the Lycosides. The male armature consists of a dorsal (in regard to the body) portion (the uncus) and of a ventral one (the valves - which have a constant fishlike shape in the Plebejiwe,'), The two are hinged to each other somewhat in the way of the lids of a shell and appear "closed" when viewed in situ. When teased out of the tissues and viewed ventrally, i-e., when the whole organ is forced open oysterwise so that its symmetrically ex- tended valves continue to point down, whereas the uncus lobes point distad from the observer, the most conspicuous thing about the upper portion is the presence of a pair of formidable semi-translucent hooks (the subunci or fakes -of a peculiar shape not found in allied genera), produced from the opposite side of the distally twinned uncus and facing each other in the manner of the stolidly raised fists of two pugilists (of the old school) with the uncus hoods lending a Ku-Klux Klan touch to the picture. The flame-shaped distal part of the candle-shaped aedeagus reaches a point between their elbows, while its proxi- mal part is propped by the fultura in/erior (furca) at the root of the valves.
In the paper already referred to, I introduced the following terms: F. for the length of the upright portion, or forearm, of the falx measured from its distal point to the apex of its elbow; H. for the length of the herdus of the falx, from the apex of its elbow to the apex of its shoulder; and U. for the length of the uncus lobe from its distal point to the apex of the shoulder of the falx. In the majority of some 500 preparations, regard- less of whether the elbow of the falx happened to be raised (in the follow-through of an "uppercut," to pursue the pugilistic image) as it is for instance in fig, ARGA. of pi. 1, or whether it remained in its normal position (i.e. with the forearm parallel to the axis of the uncus lobe), a rather curious fact was noticed, namely that the distance between the tip of the falx and the apex of the shoulder exactly equalled V. This suggested the tracing of a triangle, FHU, its lines joining three points: apex of forearm, apex of elbow, and apex of shoulder. A glance at fig. 1 will show that, according to the dimensions of forearm, humerulus and uncus lobe, this triangle assumes a different size (showing the gradual generic development) and a different shape (showing the specific relative dimensions of parts).



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19441 Genus Lyc~ides
t
ARG. C
FIG. 1. EVOLUTION AND SPECIATION OF UNCUS IN LYCBIDES (All the figures are X 33)
F- length of forearm of falx.
H- length of humerulus of falx.
u - length of uncus lobe, equal to distance between apex of falx and apex of shoulder.
FHU- triangle for measuring relative dimensions of parts. X -hypothetical ancestor; FHU = 0.25 + 0.22 + 0.22 = 0.69 mm. AGN - agnata agnata Staudinger, prep. 193, "Maralbaschi [Maralbashi, W. Sinkiang,
Central Asia]" ex coll. Weeks, M.C.Z.;
FHU = 0.33 +
0.26 + 0.30 = 0.89 mm.
ARG.A - argyrognomon Bergstrasser ssp. (ssp. anna Edw. prox.) , prep. 348, "Brewster, Washington [N. Americal, 18-VII-1940" coll. Stallings-
Turner; FHU = 0.36 + 0.33 + 0.27 = 0.96 mm. ARG.B - argyrognomon bellie~i Oberthuz, prep. 189, "Corsica [S. Europe]'' ex coll. Weeks, M.C.Z.; FHU = 0.33 + 0.30 + 0.25 = 0.88 mm. ARG.C-a~gy~ognomon Bengstr. ssp.
(ssp. opulenta Verity prox.), prep. 211, "Alto Adigo [N. Italyl 3-VII-1930,'' ex coll. Weeks, M.C.Z.; FHU = 0.39 + 0.40 + 0.27 = 1.06 mm.
SCU- scudderi scudderi Edwards, prep. 168, neotype, "Saskatchewan [N. Americal
[leg.] Kennicott," M.C.Z.; FHU = 0.45 + 0.34 + 0.34 = 1.13 mm.
SUB - subsolanus Bremer ssp., prep. 242, "Korea [E. Asia], 27-VII-1933, leg. Suk," M.C.Z.; FHU = 0.44 + 0.39 + 0.39 = 1.22 mm. MEL- wzelissa samuelis Nabokov, prep. 338, holotype, "[Albany, New Yorkl Orig. Pl. 6, fig. 6, Butt. N. Engl. Cab. S.H. Scudder," M.C.Z.; FHU = 0.57 + 0.3.5 + 0.44 = 1.36 mm.
ISM - ismenias calabricola Verity, prep. 152, "San Fili (Cosenza) , Calabria [Italyl 17-VI-1920 [leg. fam.] Querci," ex coll. Weeks, M.C.Z.; FHU = 0.74 + 0.56 + 0.49 = 1-79 mm.




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110 Psyche Bept .-Dec.
1 view evdution in Lymides as a twofold process of growth: 1. as a generic growth - involving the who& of the male geni- talic structure, so that the absolute size of the uncus (i~depmd- ently from the size of the wings) in its general graduation from the most primitive stmctures (F -I- H 4- U = about 0.9 mm,) to the most specii-dized ones (F + H + U = about 1.8 mm.) is doubled at the maximum limit of development; and 2. as a spe- cific growth - a process acting upon the relation of parts F, and U, attacking one part more strongly than the other, where- upon the latter tends to catch up with the former, producing at a certain stage stabilization and equilibrium, which eventually are again broken by unequal growth Details camot be dis- cussed here, but it may be noted that the generic growth pro- duces more robust structures in the palearctic section than it does in the nearctic one; that there is also a difference in the rhythm of the specific growth (H being the part conspicuaus1y affected in the palearctic branch, while it is the reIation U/H which grows in the nearctic branch where H is more cramped and sluggish); and that throughout the general process stunted by-products ocmr (holarctiml~y), reduction in absdute size of structure synchronizing here with reduction in size of wings. 1 have separated the extremely munerous subspecies of which some 120, most of them badly chosen and poorly described, have names (with up to four synonyms in some cases) into six specific groups. In each there is a considerabk range of racfd fluctuation in the general size of the structure, arid in F/lJ and a more limited indivkIua1 fluctuation in H/U, but there is a con- venient constance in the structural proportions (and in other structural details not mentioned here 1 of foms clustering around the main peaks of speciation. These peaks are: ugnata Staudinger : small structure, with H smaller than F and slightly smaller than U;
wgymgnomm Bergstriker: small to average? with H sub- equal to F and greater than U;
subsolums Eversmann: average, with H smaller than F and equal to u;
scudderi Edwards: small to average, with H still smaller than F and equal to U;
is not improbable that qmta produm in Turkestan a form paralleling scddm' (see Nabokov, 1.c. : g5, nota) .




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19441 Gems Lyc~ide~ 1 11
mdissa Edwards: average to large, with H much smaller than F and smaller than U ;
1
isme~ias Meigen: fairly large to very large, with H much smaller than F and greater than U,
From the arrangement on fig. 1 where selected examples of proportions are given, it will be seen that wgymgnomon, coming from an ancestral structure from which agnata was also derived (and which on the basis of certain data provided by other genera 1 am tempted, being human, to furnish with certain characters, namely with H and W both equal to 0.2 and slightly smaller than the small F), produces two branches, which run pardel to each other in the general growth of parts. A complete sequence of intergrades (more complete than I ariginaIIy thought) exists between argyrognomon and smdderi in the palearctic branch and between wgyrognumm and ~~bsoZu~w in the narctic me; and 1 would not hesitate a moment to assign to suho.Janus and sqdderi a subspecific position with the polytypic argyo- gnomon had they not been centers radiating as it were their om forms and, on the other hand, had they been separated from melissu and ismenias respectively by a definite hiatus, which is not so, since racial intergrades (with a corresponding combina- tion of pattern and structure) exist here too, It may be. added that the genus is distributed from the polar regions to just below latitude. 40' in Europe and eastern North America, and to at least 30' in western North America and Asia. Its cradle is a lost country of plenty beyond the Arctic circle of today; its nurseries are the mountains of central Asia, the Alps, and the Rockies. Seldom more than two and never more than three species are known to occur in a given geographical region, and so far as records go, not more than two species have ever been seen frequenting the same puddle or the same flowery bank. When about to draw up detailed comparative descriptions of the numerous forms, some of them new, involved in my exami- nation of this genus, 1 was confronted by the fact that the pat- tern of the Lycxnidz had never been adequately analyzed by systematists, On the other hand, none of the works especially devoted to schemes of stripes or lines deal with that family nor can I adapt anything they contain to my needs, since pattern development and correspondence in design vahes are discussed



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112 PSYC~? [Sepbhc.
by authors (Eimer, Kmnezov, Schwanwitsch, and others) from a point of view with which I entirely disagrke? Thus 1 have been forced to devise a scheme of my om. Before passing on to this scheme, certain methodoIogka1 points must be explained An extremely exact and simple method of mapping the wing characters has been suggested by the fact that the wing is crossed by a set of concentric scale lines of equal breadth (very constant1y about 0.06 mm.; sinking to 0.05 only in dwarfs and rising to 0.07 only in giants). Although a few of these lines may fork a here and there, their curved course is, on the whole, remarkably regular) and easily followed from costa to dorsm. By stating the meridian of the scale line and the parallel of the vein, the position of any pint on the wing can be given) anti by counting the scale lines occupied by a marking, the extension of the latter can be adequately measured both in its absolute size and in relation to the whole expanse of the wing. At the mot of the wing the scale 1hes are badly blurred, since the scales here are coarse and irregular, I have thus taken for 0 the scde line crossing the wing through the base of Cu? which is especially convenient as then Lhe axis of the forewing discoida1 made (ie. the two discaim or cross veins) coincides more or less with the course of the hundredth scale line {from about the 95th in average shed specimens). Out of a great number of specimens examined and rneas~ired, an average looking Lyc~ides was selected the discuida1 made of which lay exactly upon the hundredth scale ]hie (see pl. V? the model of which was a Colorado male of melissa m&sa Edwards, to which macdes R2 and R8 have been added from other hdividuals) .
When prolonged beyond the wing, the scale lines are seen to form concentric circles (the curvature of the central and distal lines, forewing, and that of the distaI ones, hindwing, showing almost gmrnetricd regularity)' These, however, are not con- centric with the termen (especially in the forewing) ' and thus 'Whiie deeply enjoying the profusion of fascinating figures provided by those authors; and of course Kumezov's mwterpiece (1915, hszctes 16pkIopt4res (Nasekomye &&uekryIye) x (I), in Fame de la Russie) is nnsurpassed by any other general survey of the morphology of Lepidopfera. 'This seems to be a more frequent occurrena in large race than in small ones, and takm place more often distally than basalTy but 1 have not yet come to any conclusion regarding the morphological value of this character. *They are concentric to the termen h wresentatives of other subfamiIies, e.g. in Thech Fabriuus (sJ.].




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the outline of the latter seem as it were carved out (as if soms body had taken a sheet of paper that happened to be neatly ruled and had cut out a butterfly, ignoring the lines), after which the transversal dispositbn of the markings was more or less adapted to the new shape (especially in the case of the mom distal markings) in consequence of which they ceased to follow the curvature of the scale lines, Its center in regard to the fore- wing lies outside the root of the latter at a point corresponding to the root of the forewing on the opposite side of the thorax, ie., at a distance from the base of the wing equal to the breadth of the body at that point; the hindwing center, however, is situated at the very root of the wing (base of costa), so that in order to make the two curvatures coincide, the right hindwing must be placed upon the right forewing in such a way as to have its hub coincide with the root of the left forewing (see plate V) . My ignorance of mathematical and mecharkal mat- ters is prodigious, ad thus 1 am quite incapable of fo1Iowing up certain lines of thought which these curious facts suggest. Four veins haw been lost in the course of the development of the Lycmidze or of their ancestors. The first to go was an additional radial nerde between ScR and Rs. The next to go was 3A of hindwing. Its more recent disappearance is suggested by the rather constant rhmiform shape of macule 2A and by a slight halving of the cretule (q.v.1 due to the occurrence of a line of weak scales (or a very slight scar) following the old 3A course upon a slightly darker ground. The last two *ins to go were 1A and M, probably more or less ~muhaneous~y, their remnants being very similar. These remnants are: the still quite definite separation of first made (q.~.) in 1A from that in Cu2 (the oldest set), the somewhat less definite (in hindwing especially so) separation of the second made (q-v.) in 1 A from that in Cu2 (a more recently evolved .set) and the distinct scar of vein IA. 1 haw treated it as an existing vein in my classifica- tion of macules, A similar scar is visible in cell RM, the intra- cellular mcuk of the hindwing being placed udw that scar (in other genera there is also an upper made), and conse- quently 1 ca11 it M. The discoidal double macde (RM) placed upon two very weak and often partly obsolescent discales, is very like macules Cu2 + 1A (the + denoting their frequent fusion). It seems likely that the third macdes in Sc and Cu2 of the hindwing travelled to their present positions dktad after



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Psyche [Sept,-Dec.
VOL. 51, PLATE V




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the disappearance of the veins that had once halved their cells. In the forewing the last radial is numbered R+ since I have not come to any conclusion as to which of the initial five veins disappeared. The stalking of Rg and R4 seems to have occurred after the (rare and weak) first and second macules in E& reached their present position from a point adjacent to cell RM; their weak condition seems due to the subsequent segrega- tion in the prison of the shortened and narrowed interspace. An examination of all known genera of Lycsenidse, clues provided by aberrational individuals and certain ontogenetic data suggest that the maculation of a given interspace develops phylogenetically in result of a series of recurrent waves or rays of pigment, each shorter than its predecessor. An initial wedge- like or gusset-like infuscation, in the proximal corner (against * cell RM) of a neutrally colored interspace, grows distad, ex- tending along the interneural fold. This ray broadens distally;