86 MR. NEWPORT ON THE ANATOMY AND DEVELOPMENT 
supported by the fact that I have never yet met with even the youngest larvæ between the 
skin and muscles of the caterpillar, but always internal to the muscles, imbedded in the 
so-called fatty tissue, between them and the alimentary canal, and always on the dorsal 
surface, and usually with its head in the direction of that of the caterpillar. I have found 
it in different stages of growth, from one-fourth to three-eighths of an inch in length (a), 
as early as the middle of August, when it is of a light pea-green colour; but I have obtained 
full-grown specimens (c, d) only from the pupa of the Sphinx, sometimes as early as the 
end of October, but more frequently not until the commencement of March, and sometimes 
as late as the end of April. Usually, one egg only is deposited in each caterpillar, but 
sometimes there are two, and both become hatched, although of the parasites one only 
arrives at maturity, as one is invariably destroyed by the other. I have the following 
entry of a fact of this kind in my note-book with the date “ March 13, 1832," which shows 
that two larvee may exist in the pupa of the Sphinx up to a late period, but that one is 
then destroyed. ‘The pupa now examined was one in which Ichneumon Atropos had 
deposited two eggs. Two larvæ had been hatched, and these were located in the lower 
part of the abdomen of the pupa. One of them was very small, being scarcely more than 
one-fourth of an inch in length, and appeared to have been dead for some time. The 
other was a fat well-fed specimen, about three-quarters of an inch in length and one-sixth 
in diameter. It seemed to have destroyed part of the fatty sacculi of the Sphinx, and 
was lying in the cavity of the body, but it had not injured the upper part of the digestive 
apparatus, the stomach, behind which it lay so imbedded that I had almost mistaken it at 
first for the intestine and colon, which had not undergone their proper change. The 
nervous system of the pupa had not been injured by the larvæ, although its changes had 
been retarded. It thus appears that the Ichneumon sometimes deposits more than one 
egg in the body of the caterpillar, as several times before this I have found two of these 
larvee in the same insect, although, I believe, never more than one of them comes to 
perfection." All my subsequent observations have confirmed this conclusion. 
The usual situation of the parasite in the Sphinx-pupa is in the tissue of the middle 
part of the body beneath the dorsal vessel and above the stomach, on which it often rests. 
This is the position of the full-fed larva in the drawing and preparation (fig. 3), and this 
ia the specimen alluded to and partly described in my second memoir on Meloë, printed 
in the Society’s Transactions, vol. xx. p. 385. It was obtained at almost the latest period 
of the larva state, on the 18th of April, 1832. The other specimens exhibited were pro- 
cured between that period and the month of October, so that the insect continues to sub- 
„Sist on the Sphinx, and probably passes into a state of hybernation with it, during the 
long interval of six months. One specimen found on the 20th of March, and removed 
zen : ee dee am water, lived several days, while another, not placed in 
tion sida " ie e Fs ms s prepare for its change to a nymph. This change 
PUPILS Si toes On. a: ea ive, as the following entry from my note-book 
i Wind RESI * x un a g a male pupa of Sphinx ligustri, a few days ago, 
Lepus ds PCs rtification, one of my old friends, the larva of Ichneumon. it 
pecimen, and laid with its anterior portion in the thorax, and its 
