Article beginning on page 159.
Psyche 3:159-161, 1880.

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PSYCHE.
ON THE NUMBER OF MOLTS OF BUTTERFLIES, WITH SOME HISTORY OF THE MOTH CALLOSAMIA PXOMETHEA. BY WILLIAM H : EDWARDS, COALBURGH, W. VA. WHEN I first began to study the history
of the lepidoptera, it was difficult to learn from any quarter how many molts lepi-
dopterous larvae underwent. No one to
whom I could apply could tell with any
assurance of certainty what was the num- ber of molts among the butterflies, and
authors either disagreed or were silent
on the subject. Burmeister (Lond. ed.,
1836, page 431) says : The caterpillars
of the butterflies molt, according to Kirby and Spence, frequently; but thrice, ac-
cording to Cuvier. The caterpillars of
the noctuae, on the contrary, molt four
times," etc.
Boisduval (Spec. Gen., v. 1, p. 46)
saj s : These molts are more or less
numerous according to the family : the
rlwpalocera passing ordinarily three and four; the greater part of the heterocera four, except some clothed species, which pass from seven to eight."
Kirby and Spence (Introd. to Ent.,
Lond. ed., 1856, p. 36) speak of "but-
terfly caterpillars throwing off three or more successive skins."
Westwood (Brit. Butt., v. 1,p. 6) says : They cast their skins several times."
Harris (Ins. injur. veg., ed. 1862, p.
259) says :
Caterpillars usually change
their skins about four times," referring to caterpillars generally.
So it will appear that, twenty years
ago, no definite information -was to be
had on the subject. It was the custom
when larvae were described, if any men-
tion of stages earlier than the last, or mature, was made, to say, " young lar-
va," "half grown," etc., with no ref-
erence to the number of molts.
During these years, and indeed since
1870, I have bred from the egg many
species of butterflies, as PAPILIOS 6, viz., ajm, philenor, asterias, troihis, turnus, cresphontes; PIERIS 3, protodice, oleracea, rupae; COLIAS 2, eurytheme, philodice;
TERIAS 1, nicippe ; DANAIS 1, archippus; ARGYNNIS 7, diana, idalia, cybele, aphro- dite, egleis, vnyrina, bellona; EUPTOIE- TA 1, Claudia; MELITAEA 1, phaeton;
PHYCIODES 3, harrisii, nycteis, tharos;
GRAPTA 3, interrogationis, comma, prog-
no; VANESSA 1, antiopa; PYRAMEIS 2,
utalanta, huntera; LIMENITIS 2, arthe-
mis, disipps; APATURA 2, celtis, clyton; NEONYMPHA 4, eurytris, sosybius, gemma,
canthus; DEBIS 1, portlandia; SATYRUS
1, dope; LIBYTHEA 1, bachmanwi;




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160 PSYCHE.
CHRYSOPHAXUS 1, - americmw, ; LYCAENA P. sisymbri, and gave dates of their oc- 2, pseuda.rgio1us.i wmyntus; PANPHILA currence. There certainly were three 4, Jiobomok, Awon, wna, cemes; Eu-
only to Seonymphu gemma, verified by
DANUS 3, bathyllus, lycidas, titgrus; me iu several broods. But in all other FHOLISORA 1, ca‰âÂuIlus 53 species, all cases there Have been four, except when but one or two to imago, and these the larvae hibernated, and then an addi- through the larval stages to chrysalis. tional molt occurred. There seems to Several others I have received in either be a necessity with the hibernators of
first or second larval stages from cor- getting rid of the rigid skin in which the respotideata, and have carried the larvae larva has passed the winter ; that .is, if to imago, as PAPILIO 1, palamedes; the hibernation has taken place during CALLIDRYAS 1, H e ; HBLICOMIA 1, the middle stages, as it does in Apatura clwritonia; ACTAULIS 1, vanillae; ERE-
and lAmenitis. In these cases very little BIA 1, texma;, LIMESITIS 1, eros; APAT-
food is taken between the molt which
URA 2, alwa, flora: making 8 species.
precedes hibernation and the one which
Besides this, Messrs. Couper, Baron, . follows it, and the larva white in leth~ir- Mead, and other currespondents have gy is actually smaller than before the bred other species, of which I have had
next previous molt.
The skin shrinks,
reports, as Papilio brevicavda and mch- and has to be cast off before the uon (the latter deterdied at my special
awakened }arva can grow.
These spe-
request by Dr. Ang. Weismann and Mr.
cies (observed), whose larvae molt five
Wrn. Buckler) Pi'm's bcdceri and @m- times in the winter brood, require hi, Ant1iocAaris stella, Danais berenice, but foiir molts during the summer. Mel-ifaea rubicunda and chalcedon, w- , in the' case of Limenitis disippus the ta satgms, PampJula etaus, 10 species, stages up to the third molt are identical thus making 71 species whose complete in the winter and summer broods, Init larval history has been observed.
It is the stage followingthe third in summer is difficult to follow the stages of the Hes- equivalent to the two stages after the third perians, as the liuvae conceal themselves in winter, and the stage after the fourth in cases of leaves, but
so far as I have of the one comes to be identical with the been able to do so, the molts in each case stage after the fifth of the other. Many have been four.
In Budamus lycidas and larvae go into lethargy immediately after Plwliswa catuZhis 1 made sure of this exclusion from the egg\ as the large Ar- the past season.
About CalMi YUS w gynnids, and probably all the Satyrids of bide I am in doubt, that is, whether there the alcipe group.* The former pass five
we three or four molts.
The early sta- molts, but probably only four in summer. ges so much resemble each other in this
epecies and pass so rapidly,,that I could *
have now hibernating young larvae of
Sutyma silvesfris, eggs of which species were not be at which stage received the fi Earon and hat&cd h ~ & e from Georgia. Mr. Baron report- at Coalburgh. They look like and behave ed three molts to both. Pieris beckeri and exactly as dop~.
&




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At any rate the small Argynnids, as
myrina and bellona, pass but four in sum- mer. Satyrus alope passes but four,
although the only brood of the year is
that of winter. In both these genera, the larvae eat nothing before lethargy, except their own egg shell, but feed for several days after awaking and before a molt
comes on.
The genera above mentioned, 011 which
observations have been made, embrace a
large proportion of those which belong
to the North American butterfly fauna,
and we may infer that butterflies of the other genera, at least those which inhabit temperate regions, will as a rule be found to behave likewise, and that the regular number of molts is four, except in cases of hibernation, three being a very rare
exception.
In the Entomologists' Monthly Mag-
azine for July 1880, Mr. Wm. Buckler,
who has had very great experience in
breeding lepidopterous larvae, contrib-
utes a paper entitled : '' Is the number of moults of lepidopterous larvae constant in the same species ?" and begins thus : " I have been impressed lately with the uncer- tainty that seems to exist as to the number of times lepidopterous larvae moult in
course of their growth, and have been
considering whence this uncertainty
springs. . . . Or is it quite certain, as many think, that the number of moults
varies in the same species ? . . . I know that the number of moults certainly
varies in different species. I have myself made sure that six is the number for
some and nine for others, as in the case Nola centonalis. . . . Any one who has
made notes on which he can depend
about the growth of any species he has
reared, would I think do good service by publishing' them," etc.
What I have said before will in some
respects answer Mr. Buckler's query,
so far as concerns North American but-
terflies at least. I have no doubt the
several species are constant in the num- ber of their molts, the exceptional cases being as I have stated.
But whether the same can be said of
all species of heterocera I am not compe- tent to say. Certain observations made
on Cullosarnia prometkea would seem to
indicate that there may be variability.
I happened last spring to have a co-
coo11 of this silk-worm moth, which I had brought in from a tulip tree, and as a
female came from it, it occurred to
me to see how many molts its larvae
might have. I have long given up breed-
ing or collecting heterocera (-though for several years I bred sphinges and bomby- cidae largely), the North American Diurn- als giving me more work than I can
properly attend to ; but I had some
curiosity to satisfy in this particular
case. I tied the subject to a tree, and
during the night it was impregnated, and next day, 19 April, it laid many eggs.
The hatching began 1 May. The first
molt took place 7 May; second molt,
11 May ; third molt, 15 May. On 22
May, or 7 days after third molt, the first larva was shut up in its cocoon. I was
much surprised at this, as I had expected four molts, and I searched the books to
see what had been said about this
species.
( To be continued on p. 171. )




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