A. L. Melander.
The Genus Tachydromia.
Psyche 17:41-62, 1910.

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PSYCHE
VOL. XVII. APRIL, 1910. No. 2.
THE GENUS TACHYDR0MIA.l
Concerning the application of the generic names Coryneta, Tachy- dromia, Platypalpus, Tachypeza and Tachista of the family Empididae there is much confusion. In his early paper, the Noutelle classifica- tion des mouches a deux ailes, bearing the date 1800, Meigen gives his forty-fourth genus the name Coryneta, describing it as follows. "An- tennes &, deux articulations: la premiere petite, h6riss6e de polls; la seconde conique, termin6e par un poi1 barbu. Trompe perpendicu- laire.
Cuisses des jambes du milieu enfl6es. Le tibia arm6 a l'ex- tremit6 d'un piquant.
Les ailes crois6es."
No species of the genus are mentioned by name, but Meigen states that he has recognized three species. In 1803 in his revision of this paper in Illiger's Magazine, Meigen gave the name Tachydromia to the fifty-second genus, mentioning .however this time two species, cursitans Fabricius and cimicoides Fabricius. His diagnosis of Tachydromia is as follows. "Die Fuhlerhorner vorgestrekkt, zwei- gliederig: das erste Glied becherforinig; das zweite kegel-formig in eine Borste auslaufend. Der Russel senk-recht. Schenkel der Mittelfusse dikk, stachlig.
Die Fliigel flach parallel."
It will be noted that the two descriptions read much alike, which is why Bezzi (in lit.) and Hendel have concluded that both refer to the same genus, and that therefore the older name Coryneta should be given preference. The Nouvelle Classification has been an extremely rare paper. But three copies are known to exist, one at the Academy of Natural Sciences, Philadelphia, a second owned by Professor Hey- den, and another belonging to the late Osten Sacken, and now in the possession of Dr. Hendel. Because of the obscureness of this early paper of Meigen it has been neglected by all writers. Its names are not given in the nomenclators, and even Meigen himself ignored its 1 Contribution from the Zoological Laboratory of the State College of Washington. 2 Verhandl. k. k. 2001.-bot. Gesellsch., Wien. 1908. pp. 43-69. 41
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Pu&e 17:41-63 (1910). hup //psyche cnlclub org/17/17-IMl.htiiil



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42 Psyche [April
existence in his later works, as if ashamed of the curious meaningless names of his first publication. The diagnoses are brief, general and ambiguous, and, since no species are mentioned the identity of the genera would have remained mostly unknown, were it not that some of the early descriptions bear a similarity to the corresponding ones of the later paper. In nearly all cases however the generic names of 1800 are entirely different from those Meigen later used. The genera of Meigen's second contribution are well known, as for most of them typical species were cited at the beginning, and their names have been in constant usage for our commonest flies for more than a century. Even by this method of comparison and elimination many of the 1800 genera will never be understood.
This early publication of Meigen remained entirely ignored until Dr. F. Hendel republished it entirely in the Verhandlungen of the Wiener Gesellschaft. If we were to accept his guesses as to the identity of these early genera we would overthrow such well-known names as Ceraiopogon, Odontomyia, Eristalis, etc., as well as the long established type-genera of over a dozen families of diptera. But much of his evidence is insecure. The paper is worthless if not interpreted by Meigen's later works, the date of publication cannot be verified, there is even doubt if the paper was distributed on the date it bears, and nowhere are any species cited, so the genera are i10t true binomial conceptions. This last condition alone should not be followed too closely, for many of Meigen's genera of 1803 and 1804 were likewise published without mention of species.
Naturally to exhume these forgotten names has stirred up much discussion, and in the short interim since Hendel's republishing, there have been a score of opinions given out by various biologists. These opinions are sometimes conflicting but in the main zoologists strongly decry using the law of priority to bolster up such speciesless genera as Meigen's earliest. I shall give a list of the articles that have come to my notice bearing directly or indirectly on the principle of whether or not to adopt the newly disinterred genera. I11 this long parley the concrete example of Meigen's paper has been lost sight of by many of the contributors, and merely the principle has been under discussion, but nevertheless the entire argument outlined below was caused by the appearance of Hendel's reprint. A short digest of the articles will help to correlate the ideas advanced. Professor Aldrich wrote in hopes of squelching Hendel's paper, to



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19101 Melander - The Genus Tachydromia 43 deter others from using the ancient names. Yet Kertksz' last volume of the Catalogus Dipterorum hujusque descriptorum, volume v., 1909, adopts the family name Omphralidae for the Scenopinidae; his Catalogue of palaearctic diptera uses five of the early names in volume ..a
111; while Czerny in a paper on Spanish Diptera has discarded the
family names Scatophagidae and Trypetidae, as he uses for them Meigen's earlier type genera Scopeuma and Euribia, forming thereby the family names Sc'opeumatidae and Euribiidae. However, Czerny does not use Meigen's early Cypsela to replace Borborus, as was ad- vocated in Hendel's reprint.
Volume iii of the palaearctic catalogue has dispensed with the following well known genera on the plea of priority: Ephippium, Oxyceru, Odontmqia, Xylophaw, Haematopota, Subida and Leptis. Surely the dipterist has a bewildering memory-lesson before him. It is strongly to be urged in this period of nomenclatural unrest that writers be not too hasty in adopting the suggestions of Dr. Hendel. The trend of public opinion is that genera without species shall have no place in our system of classification. I11 view of the projected action
of the Committee of the International Congress of Zoologists (see number 23 below), it would be decidedly rash to rush into publications the once-discarded names of 1800.
It would be better to hold in
abeyance any personal desires for Meigen's first names until the Committee can rectify the Code on this question. Such conservatism
may prevent a premature overthrow of the names of our commonest genera, and might spare our overburdened literature from most con- fusing rearrangements of synonyms.
1. Nature, August 27, 1908, pp. 394-395. A- composite letter by British zoologists deploring the fact that a strict adherence to rules sometinies brings unfortunate consequences. 2. N. Banks, Science, xxviii.
Advises others who have rare papers to republish them. 3. S. W. Williston, Manual, 3rd. edit. p. 390, 1908. "Hendel would have deserved the thanks of a long suffering public had he withheld these copies instead of republishing." 4. M. Bezzi, Wiener entorn. Zeit. xxvii. 252, Sept. 1908. Comments on the adoption of the names of 1800 that come in vol. iii. of Kertesz' Catalogue of palaearctic diptera, a course in which, naturally, he approves.
- --
1 Verb. k. I<. zoo1.-lmt. Gesellsc-h., Wien, vol. 59, 1909.



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Psi/che 1 April
J. M. Aldrich, Canad. Ent. xl. 370-373.
Oct. 1908.
Compares resurrecting the 1800 paper to finding some old grant to Indian lands. Every possible objection should be made before accep- ing them; a fla,wless case must be made out and the identification of the older genera is full of flaws. "Let justice be done" exclaims Hendel. To whom? Certainly not to Meigen by accepting this paper.
J. M. Aldrich, Canad. Ent. xl. 432, Nov. 1908. Quotes from Bezzi7s paper (number 4, above) in the Wiener entomo- logische Zeitung. Hendel (number 9, below) says that the quotation is mis-applied.
D. W. Coquillett, Canad. Ent. xl. 457, Dec. 1908. Pleads for the adoption of the early names, citing rules from the code to cover his argument. Does not believe in obstructing the progress of nomenclature by discrediting Hendel's find. P. H. Verrall, British Flies, v. 772, 1909. Meigen's 1800 genera are not legally established. Does not concur
with Coquillett's " aggravated7' pleading (no. 7). I?. Hendel, Wiener entom. Zeit. xxviii. 33-36? Feb. 1909. Discusses the comments in numbers 3, 4, 5, 6, 7, and 8. Stability of
nomenclature can be had only by a st,rict adherence to the law of priority. Since Meigen described only genera, but gave the number of species that he knew, and in the preface designated his work as a prodromus of a later work designed to contain only the genera, he can not be said to have carelessly neglected the principles of binary nomen- clature. Hendel states that 39 of the Brachycera genera can be imme- diately recognized from the descriptions alone. The future alone can tell whether the majority of dipterists will decide for continuity or for priority.
T. D. A. Cockerell, Science, xxix. 339, Feb. 26, 1909. Calls for a postal vote of opinions about genera without species. "A
genus without species has no type, no content, and apparently has no place in our systems of classification." J. M. Aldrich, Canad. Ent. xli. 103, March, 1909. In a review of Verra117s British Flies, Aldrich quotes the discovery of certain Chicago historians that the annulment of one of the marriages of King Henry VIII. was invalid, and that, consequently, King Edward VII. is not King of England. This discovery is on a par with the reasoning that Meigenla earliest genera should claim priority. T. D. A. Cockerell, Science, xxix. 813, May 21, 1909. The result of the postal vote (number 10) shows the majority of voters not in favor of resurrecting the names of speciesless genera. A. A. GirauL, Science, xxix. 814, May 21, 1909. A genus described without a species is non-existent. Its name has no
status until some definite type species has been designated. J. A. Allen, Science, xxix. 935, June 11, 1909. 'Prior to 1810 hundreds of genera now in current use were proposed -
solely on the basis of a diagnosis; although they were accepted and



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Melander - The Genus Tachydromia
45
have been in use from the date of their proposal, many of them were without designated types for half a century." "Apparently each case should be dealt with solely on its own merits." F. N. Balch, Science, xxix. 998, June 25, 1909. In a paper, "A Lawyer on the Nomenclature Question" Mr. Balch advocates an International Court with absolute power to settle every- thing nomenclatorial. The priority rule was not intended to be the superstition and incubus it has become. "Questions of nomenclature are of utterly insignificant importance so only that they be settled one way or the other, quickly, definitely, and permanently.'' F. A. Bather, Ann. Mag. Nat. Hist. (8) iv. 37-42, July, 1909. In an article "Some Common Crinoid Names and the Fixation of Nomenclature," Dr. Bather advocates the establishment of a court of nomenclature.
Wm. H. Dall, Science, xxx. 149, July 30, 1909. Most questions of nomenclature can be answered by a serious study of the Code. For the few other cases he advocates giving the Committee power of decision.
A. N. Caudell, Science, xxx. 210, August 13, 1909. "How can we get a type for a genus where there were no species origi- nally included? "
F. A. Bather, Science, xxx. 341, Sept. 10, 1909. Advocates a Court for the two cases, first, where the application of the Code is obscure, and second, where its application is clear, but the consequences at the same time would be exceedingly unfortunate. J. A. Allen, Science, xxx. 365, Sept. 17, 1909. '(The only point is whether they are good genera or bad genera - in other words whether they are identifiable or unidentifiable from the basis furnished by the original founder." J. Dwight, Jr. Science, xxx. 526, Oct'. 15, 1909. "Zoological nomenclature to-day seems to be little more than an intricate game of names, fascinating sport for its faithful devotees, but an intolerable nuisance for the uninitiated many." "Priority is rather a bog from which the nomenclatorial muck-rakers exhume the fossil remains of a past age." "It is not justice for the dead zoologist that we need so much as justice for the living, and even now the dead get no recognition if they violate the rules of a game unknown in their day."
A. S. Hitchcock, Science, xxx. 597, Oct. 29, 1909. Believes it impractical for a committee to prepare a list of names that will be stable, because of the changing: state of biological knowledge. J. A. Allen, Science, xxx. 596, October 29, 1909. Proposes the following recommendation for the International Com- mittee. "A generic name proposed without mention of any described species is invalid unless it is accompanied by a diagnosis of such a character as to indicate that it is based on a previously known species, or group of species, that can be unequivocally identified as the basis of the diagnosis."
8




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46 Psyche [April
Therefore, instead of worrying over just which of the genera can be identified, it will be vastly better for the present to ignore entirely the Nouvelle Classification. It is absurd rigidly to apply modern rules of nomenclature to the works of the early writers, when as in this instance no good can be subserved, and a most confusing and "com- plete revolution in dipterological nomenclature" would result, a condition that Dr. Hendel seems eagerly to have hoped for. It is commendable to make use of the law of priority when stability and permanence will be guaranteed, but in the present case it is too risky to accept Dr. Hendel's views and make the wholesale changes he has suggested. Dr. Stiles has remark'ed that "neither the commission nor the congress has any power to force zoologists and others to accept the International Rules." I believe that my dipterist fellow workers should feel that one such occasion confronts them, if rules are to be construed, or misconstrued, to bolster up the once-discarded names. With this digression we may disregard the name Coryneta, and take up the name Tachydromia. As just mentioned, Meigen assigned Musca cursitans Fabricius and cimicoides Fabricius to his genus. The first of these was an erroneous determination which was afterwards named major by Zetterstedt. Cimicoides Fabricius is a synonym of arrogans Linneus, but Meigen was confused in his identification here too, as a part of the specimens he thought were cimicoides he afterward described as connexa. Meigen had therefore three species before him, of which two were undescribed, and the third had previously been named arrogans by Linneus. Obviously, according to modern rulings, the type of Tachzjdromia must be selected from these three, and as arrogans was the only described species among Meigen's material, that species would probably be construed as the type. But neither arrogans nor connexa has the middle femora enlarged, nor are their middle tibiae spurred. Therefore they disagree with the only salient point of the diagnosis. For that reason, according to our present ideas, neither would have been selected as the type, and the honor of serving as type of Tachydromia should have been bestowed on Meigen's cursitans (major Zett.). The old genus has been dismembered, the separated genera have received their types, and our present ideals have not been fulfilled, because of the everlasting blundering between personal whims and priority laws.
Article 30 of the Code states: "If the original type of a genus was not indicated, the author who first subdivides the genus may apply the



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19101 Melander - The Genus Tachydromia 47 name of the original genus to such restricted genus or subgenus as may be judged advisable, and such assignment is not subject to subsequent change." Dr. Stiles has given a personal ruling further that "If an author, in publishing a genus with more than one valid species, fails to designate or to indicate its type, any subsequent author may select the type, and such designation is not subject to change." Although
this is a personal opinion its soundness is apparent. With these cita- tions, we may take up the subsequent history of Meigen's Tachy- - dromia.
Meigen's early conception of the genus was the same as our present idea of the subfamily Tachydromiinae, or even the combined sub- families Tachydromiinae and Hemerodromiinae, and in this he was followed by the earlier writers, such as Fallen. In 1822 in the third volunle of the Systematische Beschreibungen Meigen separated from Tachydromia the genera Hemerodromia and Drapetis. The remaining Tachydromias he grouped into two divisions, A and B, with his cimicoides in A. and his cursitans in B, but still retaining all in the genus Tachydromia. Macquart in 1827 bestowed the name Platy- palpus on division B which was the larger group, keeping the name Tachydromia for the first group, but Meigen not knowing this renamed the first division Tachypeza, to retain the original name for the larger division. This change was published in 1830, and later he refused to adopt Macquart's name because he thought his own ideas were better. In a paper in the Zeitschrift fuer Entomologie, published in Breslau in 1863 Loew discussed the question at length and following Meigen discarded the name Platypalpus because it is a poorly formed com- pound of Greek and Latin. For the larger group, or those species related to cursitans, he retained the name Tachydromia. The re- mainder of the genus he subdivided into Tachypeza, Tachista, Dysa- letria, and Phoneutisca, bestowing the name Tachista on those species grouped about cimicoides. The majority of the prominent European dipterists have adopted this view principally out of deference to Meigen and Loew.
The date of publication of the name Platypalpus is certain, and its designation is unquestionable. We have therefore no recourse but to accept it as a valid name. To this genus belongs the cursitans of Meigen's original Tachydromia. Eliminating this species, the cimi- 1 Bull. 24, Hygienic Laboratory, p. 27 (1905) Rule 10.



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48 Psyche [April
coides of Meigen should be the type of the restricted Tachydromia. Coquillett however has designated connexa as the type, forgetting that part of Meigen's cimicoides belonged to Linnaeus' early species arro- guns. This however will not invalidate the limitations of the restricted Tachydromia, as arroqans and connexa are very closely related spe- cies, certainly congeneric.
The status of the old genus Tachydromia is therefore as follows. Front and middle femora thickened: Division B. Meigen.
Platypalpus Macquart, Westwood, Blanchard, Walker, Schiner, Philippi, Coquillett, Melander.
Tachydromia Meigen, Burmeister, Zetterstedt, Berendt, Scholtz. Bonsdorff, Loew, Bigot, Mik, Strobl, Becker, Kertesz, Bezzi, Frey. Phoroxypha Rondani, Coquillett.
Front femora thickened: Division A. Meigen. Anal cell imperfect. . . . . . . . . . . . . . . . . . . . . . . . . . Tachypeza Meigen, Loew.
Anal cell completely wanting. . . . . . . . . . . . Tachydromia Meigen, Coquillett. I
Tachista Loew, Becker.
The type species of these genera are as follows: Platypalpus. Type species cursitans Fabricius, indicated by Westwood in 1840.
It is quite likely that Westwood had Meigen's original cursitans in view, in which case the type should be major Zetterstedt. Tachypeza. Type species nubila Meigen. Rondani in 1856 designated \;å´*nervos Meigen as the type, and this is a synonym of nubila. Tachydromia. Type species connexa Meigen. As explained before Meigen indicated two species, cursitans and cimicoides. As the type species should
be one of those originally listed by the describer elimination leaves cimi- coides as the type, since Meigen's cursitans belongs to the subsequently erected genus Platypalpus. Meigen's cimicoides included two species, arrogans Linnaeus and the later described connexa Meigen, the second of which Mr. Coquillett has designated as the type. During the last half century a number of other genera have been pro- posed for new material rather than as constrictions of the older genus. The relationships of these genera can be seen from the following synopsis of the present subfamily Tachydromiinae. All the known genera and sub-genera are included.




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Melander - The Genus Tachydromia
Genera and Subgenera of the Tachydromiice. Thorax slender, humeri large, strongly constricted: palpi narrow: legs not bristly: front femora thickest.
First basal cell much shorter than the second: black species. Anal cell present : arista terminal. ................ Tachypeza Meigen. Anal cell completely wanting.
Arista terminal or sub-terminal:
marginal cell long.
Tachydromia Meigen.
Arista sub-dorsal: second vein abruptly recurved. Phoneutisca Loew.
First basal cell longer than second; outer angle only of anal cell present: yellow species. .................................. .Dysaletria Loew Thorax broad: humeri rarely large: legs hairy and usually with bristles: palpi usually broad.
First basal cell shorter than second: eyes close together, especially below the antennae.
Arista terminal.
Anal cell complete or incompletely formed. Front and middle femora thickened: middle femora with a double row of spines beneath: middle tibiae ending in a spur: eyes ..............
separated : palpi broad.
Platy palpus Macquart.
...............
Last joint of tarsi normal.
.Platypalpus s. str.
Last joint of anterior tarsi greatly lengthened. Cleptodromia Corti.
Femora not thickened: middle legs without spurs and with minute or no spines : eyes contiguous: palpi small: basal cells subequal. Sy mballo phthalmus Becker.
Anal cell wholly wanting: posterior femora more or less thickened. Drapetis Meigen.
Body robust, abdomen shorter than thorax: Wings broad, not ciliate.
..............
Third antenna1 joint short-oval.
.Drapetis s. str.
Third antenna1 joint lanceolate .......... Elaphropeza Macquart. Body more slender : abdomen longer than thorax : wings cuneiform : ......................
costa long ciliate. Ctenodrapetis Bezzi. ................. Arista dorsal : front femora thickened. Stilpon Loew. First basal cell equal to or longer than second: more or less opaque pollinose species: eyes usually widely separated on the face. Arista dorsal.
.....
Wings less than one-third the abdomen.
.Thinodromia Melander.
.. Wings surpassing the abdomen, anal cell faint. Halsanalotes Becker.
Arista terminal.
Antennae three-jointed: legs thick and bristly: eyes very small. Coloboneura Melander.
Antennae two-jointed: legs but little thickened and with few bristles, ............................
face narrow. Chersodromia Walker.




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[ Pszj che
[April
Tachydromia sens. str.
Minute, slender flies of shining jet-black color and almost devoid of hairs and bristles.
Head globular, eyes large, with large facets, in both sexes broadly contiguous on the face; front narrow, its sides nearly parallel, and but slightly diverging toward the vertex; three ocelli present; occiput broad, produced sub-conically at the neck and provided with sparse short bristles. Antennae short, two-jointed, the outer joint short rounded oval, with the long slender nearly bare arista terminal or nearly so. Proboscis shorter than the head, rigid, vertical: palpi applied against the proboscis and tipped with several short bristles.
Thorax longer than broad, not greatly convex, not truncate in front but considerably narrowed from the wings forward; humeri remarka- bly enlarged and separated from the narrow central part of the meso- notum by more or less deep furrows; a prealar lateral bristle on meso- notum; scutellum normally with two pairs of short marginal bristles, the basal pair microscopic, usually no other thoracic bristles or hairs present. Hypopygium small, more or less globular, or triangular in outline, terminal. Legs slender, the front femora somewhat thickened, devoid of bristles, but with microscopic hairs, those of the under side of the front tibiae serrately arranged, no spurs or conspicuous spines present. Sometimes the male legs have small spines on the middle femora or tibiae beneath. Wings narrow, costa ending at the fourth vein and sometimes thickened beyond the insertion of the first vein, hind margin of the wing short ciliate; no trace of an anal cell present.