RESEARCHES ON THE NERVOUS SYSTEM OF INSECTS. 291 
clematis when I saw them; their numbers must have been 
enormous. The fact, too, of pups remaining dormant through 
more than one season 1s every year becoming more established. 
The different entomological experiences of every season are of 
interest, and it is this which has induced me to pen these rambling 
notes. 
Maldon, Essex, November, 1879. 
ANATOMICAL AND MORPHOLOGICAL RESEARCHES ON 
THE NERVOUS SYSTEM OF INSECTS. 
Translated from the French of M. Ep. Branpt in the ‘ Comptes Rendus.’ 
By J. W, Srater. 
THESE researches have been effected on 1032 species belonging 
to different orders of insects, as well as on a great number of 
larve. They bear upon the metamorphoses of the nervous system 
in fifty species, and are destined as elements for the comparative 
anatomy, and especially for the morphology of this part of the 
organism of insects. The following are the principal novel 
results :— 
1. Certain insects, such as the genera Lthizotrogus, Stylops, 
Hydrometra, have not a distinct sub-cesophagian ganglion. 
Hitherto it was supposed that this ganglion was distinct from the 
following ganglia in all insects, and this character was considered 
as distinguishing their nervous system from that of the other 
Arthropoda. 
2. The ‘ pedunculated bodies” of Dujardin, or the convolu- 
tions of the brain, are found not merely in some insects, as 
hitherto admitted, but in all, in a higher or lower state of 
development. 
3. In certain insects differences in the development of these 
convolutions are met with, even in different individuals of the 
same species. Thisis the case, e.g., among the social Hymenoptera, 
such as ants, wasps, and bees. ‘The assertion of Mr. Wagner 
that among bees these parts are found in the females and the 
workers, but not in the males, is inexact. ‘They are found in the 
males, not only of bees, but of all insects. Nevertheless, among 
social species the development of these organs is much less 
considerable than in the females and workers. 
4. In general the development of that part of the brain 
