ZOOLOGY. 321 



scribes certain pedunculate bodies whose development, as 

 originally discovered by Dujardin, corresponds with the de- 

 gree of development of the instincts and intelligence in the 

 different species. Brandt's researches now enable him to 

 prove that this is the case also for the different sexes of the 

 same species. Thus in the worker of the honey-bee they are 

 of immense size, while they are slightly developed in the 

 queen and in the males. 



It has usually been supposed that all the silk-worm moths 

 issue from the cocoon by moistening the threads and pushing 

 through them. This is, however, not the case, says Dr. 

 Packard, with Actias lima, a large, handsome, pale- green 

 moth, Avith long "tails" on its hind wings. His attention 

 Avas called to a rattling, cutting, or tearing noise issuing 

 from a cocoon of this moth. On looking at the cocoon, a 

 sharp black point was seen moving to and fro, and then an- 

 other, until both points had cut a slit, through which the 

 shoulders of the moth could be seen. The hole is made in a 

 minute or two, and the moth works its way at once out of 

 the slit. The wings at this time being very small and flab- 

 by, the points stick out, and can be used for the purpose in- 

 dicated. In about an hour after exclusion from the cocoon 

 the wings become fully expanded ; but the black points can 

 still be seen through the hairs immediately at the base of 

 the wings. In this case no fluid was seen to exude from the 

 moth, and the cocoon was perfectly dry. 



This cutting apparatus has also been found to exist in 

 Platysamia Cecrqpia, P. Promethea, Telea Polyphemus of 

 the United States, in a Texan Attacus and a second species 

 from Nicaragua, and in Attacus Amazonia Pack., from Pebas, 

 Peru ; also in two European species, Endromis versicolor and 

 Saturnia pavonia-minor. The spines are feebly developed 

 in Pombyx mori, the common silk-worm, which secretes a 

 fluid, softening the threads of its cocoon, and enabling the 

 moth to press through them, though it cuts a few threads. 



Dr. Fritz Miiller describes a curious instance of commen- 

 salism in two larva? of some unknown Pepidoptera. He says 

 the larger caterpillar, which has a red head and is protected 

 from enemies by long-branched white stinging hairs, lives 

 on mulberry and other trees. Like other protected cater- 

 pillars, it is light-colored and sits on the upper surface of the 



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