360 
NATURAL HISTORY OF THE BLISTERING FLY. 
glions. The first is situated in the head, and seems to result from 
the junction of the nervous cords that the brain sends from be- 
hind, and which going downwards envelop the oesophagus like a 
collar. Two longitudinal cords make it communicate with the 
posterior ganglion, which, as well as the two following ganglia, 
belong to the thorax, and which are much larger than the abdomi- 
nal. On each side of the thorax the ganglia send out several 
nerves ; and what is very curious, the two cords which unite the 
second ganglion to the third cross one another about their middle ; 
that which arises on the right side of the ganglion in the meso- 
thorax. 
The circulatory system consists, as in all the insects, in a very 
simple vessel situated on the back, going from the head to the 
abdomen and pulsating distinctly. 
The respiratory system resembles the others of the coleoptera. 
It is composed of a number of stigmata, placed on the side of the 
body, from which recede a number of ramusculi, that finally termi- 
nate in all the organs of the body, carrying thither the aerial fluid. 
The digestive organs are very complicated. The extremity of 
the mouth speedily terminates in a long, muscular, smooth, cylin- 
droid oesophagus, which, even in the thorax, passes into a stomach. 
This again goes into the abdomen, which it fills in a great measure. 
The inferior surface lies on the nervous cord and on the muscles of 
the belly, having an elongated form scattered about, and more ap- 
parent in the full than in the collapsed state. The stomach termi- 
nates in the intestine in a peculiar way. There is a valve formed 
by the union of several small kidney-shaped bodies floating, and 
merely attached by their external sides. They are six in number, 
and from each of them there emanates a small biliary vessel. 
The small intestine takes its origin abruptly from the stomach : 
at first it is pretty large, but it speedily contracts, passes backwards, 
bends again obliquely in front, turns over again on itself, forms a 
second bend, and passes directly to the posterior part. This, as it 
is swelled, may be considered the caecum, and terminates in the 
rectum, which is narrow and very short. 
The generative organs in the male are the same as in most of 
the other insects, — a testicle, vasa deferentia, vesicular seminales, 
spermatic cord, and an organ for copulation. The testicles are per- 
fectly spherical, and of a very curious organization. There are 
several distinct parts also in the female ; such as the ovary, calices, 
sebaceous glands, vesicules, and vagina; and at the orifice of the 
latter there are generally to be found bony substances. 
ERRATUM IN THE LAST NUMBER. 
Line 9, page 249, for “ specific gravity which holds," read " specific gravity bottle which holds." 
