Article beginning on page 28.
Psyche 5:28-29, 1888.

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28 PSTcHE. [March 18%
deeply suffused with red ; in this state they can be found through June and
July, when, however, they are less
common than at other times : they
reach maturity about the tenth of Aug-
ust, but occur throughout the summer
from May to September, being the most
abundant in August.
I would here mention another hem-
ipteron that affects the same plants,
through July and August, the Liburnia
dorsalis of Fitch, who described it
under the Fabrician genus Delfhax.
Like the foregoing species it derives
protection by its close resemblance to
the inflorescence of its native grasses, being of a soiled yellow or testaceous
color with a darker dorsal stripe. It is not a common species here, and is dif-
ficult to capture as it is very shy and
agile, and when approached leaps so
quickly that the eye cannot follow it.
I have never taken the young.
VARIABLE NUMBER OF MOLTS OF INSECTS.
BY ANNA KATHERINA DIMMOCK, CAMBRIDGE, MASS, The first notes given below are trans-
lated from a paper by Alfred Wailly,
entitled "Educations d'attaciens sbrici- g6nes faites il Norbiton, Surrey, Angle- terre, en 1884" (Bull. d'insectol. agri- cole, Nov. 1885, v. 10, p. 173-174).
'In my English article, recently pub-
lished in the Journal of the Society of
arts, of London, I have given certain
accounts of the curious system employed
by Mr. Weniger in rearing lepidoptera
and ofthe extraordinary results obtained by him. He rears the larvae in a large
glass box, a green-house in miniature,
heatedby a kerosene lamp, upon which
is placed a saucer filled with water.
The larvae, kept at a uniform tempera-
ture of about 25 degrees centigrade, live in an atmosphere chaiged with the
vapors of water and kerosene, and in-
stead of dying of disease, they develop
with extraordinary rapidity. I have
seen the larvae of Antheraea mylitta,
hatched seven days after the deposition
of the eggs, arriving at their last stage towards the end of a month. Aftacus
atlas was reared in a like manner, and
fourteen days after the formation of the cocoons, the emergence of the moths
took place ; but not a single copulation was obtained. Many delicate species
difficult to rear, ha& been reared in
this manner with great success.
"There is also a fact which, I think,
here merits attention. The larvae of
Antheraea mylitta and of Ceratocawct
imperiaZis, species considered as hav-
ing six stages, and which, when. reared
under normal conditions actually have
the six stages, when reared in this
Pswhe 5 028-29 (pre.1903). hfp //psyche aitclub org/5/5.0028 html



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March 18% PSYCHE. 29
warm, moist atmosphere have but five
stages ; Mr. Weniger tells me that there was no error on his part as to the num-
ber of stages ; none were overlooked.
"My correspondent in Ceylon, who
has for many years reared Antheraea
&&a, likewise asserts in an article
published by him in a journal at Co-
lombo, and which I have lately read,
that the mylitta race which he reared
had but five stages ; in Ceylon too the
climate is warm and moist.
LiPlatysamia cecro~ia has also six
stages, but cannot this likewise have
but five, reared under these same condi- tions? May we not conclude from these
facts that certain species of lepidoptera can have many or fewer stages accord-
ing to the conditions or according to the way in which they are reared? Further
observations will be made on this sub-
ject which I shall submit to the society." In connection with this article by Mr.
Wailly, it may be well to mention a few
more observations on this interesting
subject. Dr. C. V. Riley (1st ann.
rept. state entom. Mo., 1869, p. 145),
observed that the larvae of Orgyia leu-
costigma which produced females had
four molts, while those producing males
had but three. Mr. J. Hellins (Entoni.
month. mag., 1881, v. 18, p. 86)
noticed, apparently, no sexual difference as regards the number of molts of Or-
gyia antipa, having reared four larvae
which molted as follows : one male molt- ing three, another one four times ; one
female molting four, another one five
times. This is at variance with Dr.
Riley's statements above noted. Yet
another observer, Mr. N. Coleman
(Papilio, 1882, v. 2, p. 165)~ noticed
the factthat a certain larva of Org'yia
leucostigwza, bred at the same time, and under the same conditions as others of
its species, molted once more than did
any of the others, and that this individ- ual, upon emergence from the cocoon,
proved to be a female. The variability
of the number of molts of Orgyia leu-
costigma is evidently for the purpose of enabling the female to attain its full
size, which is, in that genus, considera- bly larger than that of the male, but
there is possibly a variation in the nurn- her of molts that is due to climatic in- fluences, corresponding, therefore, in a way, to the results obtained by Mr.
Weniger.
Dr. C. V. Riley disagrees with Mr.
Wailly as to the number of molts of At-
tacus cecro$ia, the former (Amer.
entom., Feb., 1870, v. 2, p. roo) record- ing but five, the latter (Bull. Soc. ac- clim. France, May 1882, s. 3, v. 9, p.
266-267) six stages. Might not this be
due to climatic influences? Mr. W : H :
Edwards stated (Psyche, 1881, v. 3, p.
171) that he found upon rearing Callo-
samiaċ´prumethe that the larvae molted
but three times, while Mr. Lintner
(Entom. contributions, no. 3, 1874, p.
126), believes the larva of this species to have four molts. As Mr. Edwards'
specimens were reared farther south than were Mr.
Lintner's, it would appear
that this instance, if due to climatic in- fluence, was as would be expected, i. e., that the larvae reared at the north had
more molts than those reared at the
south.




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