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LIFE HISTORY OF PLEOTOMUS PALLENS LEC. 
BY HELEN SELINA KING, AUSTIN, TEXAS. 
The habitat of this species of the sub- 
tribe Lampyrini is western Texas, where 
the mature form appears in May, a month 
later than several species of Photinus. 
Both sexes are phosphorescent, the % feebly 
so, emitting a greenish light, without rays, 
but sufficiently bright to betray his pres- 
ence; the ? is much more brilliant, her 
light being sufficient to show not only her 
body, but also surrounding objects for a 
distance of several centimetres. After ovi- 
position this light declines, and the female, 
who seems to have assumed the perfect 
form for the purpose alone of laying eggs, 
soon dies. She does not feed, and is too 
helpless to move far from the place of her 
final metamorphosis, owing to the feeble 
support which her disproportioned body 
receives from her feet. When creeping, 
as she does by spasmodic efforts, she touches 
objects with her palpi, and moves her head 
from side to side. The eggs are deposited 
in one or more pits, which the female makes 
in the soft moist earth with her abdomen. 
The eggs are smooth, round, pale yel- 
lowish, about the size of black mustard 
seed, and, as far as I am aware, not phos- 
phorescent. In six weeks they produce 
young larvae 4 mm. long, cinereous on 
dorsum, dull white on venter, and emitting 
light from the ventral surface of the poste- 
rior segment. When fully grown, the larva, 
except that the color is different, and the 
body is less depressed, is precisely similar 
to that of the commonest species of Pho- 
tinus larva found here, which is perfectly 
represented in figure 431 of Packard’s 
‘* Guide to the Study of Insects.” It has 
twelve segments exclusive of the head, 
which latter is composed of two flattened 
narrower segments, the inner one forming 
the neck, and both retractile within the 
thorax. It feeds on snails; and sheds its 
larval skin at least twice, possibly oftener, 
before reaching maturity. Under confine- 
ment in a pot of earth, with snails for food, « 
it assumes the pupa state in about seven 
weeks, but it may attain its growth sooner 
when at large. Both the larval moults and 
the transformation to pupa are performed 
by the splitting of the membrane on the 
pleura through the first three segments, and 
its removal over the posterior end of the 
abdomen. 
The shield of the $ pupa immediately 
after its liberation from the larval skin, 
seems to consist of two fused segments ; 
the three following segments are narrow, 
and the middle one of these has a transverse 
depression suggesting the fusion of two 
