LIST OF ENTOMOLOGICAL WORKS. 295 



cray-fish in the act of casting their shells ; i. e. with the old shell 

 not completely thrown off, but still adhering to the animal. Of the 

 precise mode and manner in which they disengage themselves from 

 their old shells, I regret I can give no particular account. I can 

 state, however, that the shell is cast entire, not broken into pieces, 

 nor split above, so that the cray-fish, as Ave might expect, must crawl 

 out from the fore-part beneath. The operation of casting the shell, 

 I should conclude, is not confined to any one fixed period of the 

 year, but is regulated by other causes. My visits to the brook in 

 question were made in the months of July and August ; at which 

 season, as already stated, some specimens were to be found which 

 had recently undergone the change, others were about to undergo it ; 

 but by far the greater number exhibited no signs either of recent or 

 future casting of the shell. — Magazine of Natural Histor//, Vol. 

 VIII. p. 468. 



Mr. Thompson, it should seem, maintains the existence of trans- 

 formations throughout the Crustacea, similar, I suppose, to those of 

 the larvae of insects. Now here, again, I cannot speak to the fact 

 as regards crabs and lobsters ; and I know that there are anoma- 

 lies in nature. But the young of the fresh-water crayfish most 

 unquestionably are hatched, and come into the world of the same shape 

 os the adult ones. In the above-mentioned brook, I have caught 

 cray-fish with the ova apparently just hatched, and the minute 

 young not having yet, as it were, left the nest, but still adhering to 

 the under part of the parent. — Ibid. p. 469. 



The same number of the Magazine of Natural History con- 

 tains a notice, with figures, of a new Phyllosoma, by Mr. 

 Lukis ; also a notice, with figures, of Squilla Deswarestii, by 

 the same gentleman ; the figures are admirably cut in wood. 

 Some observations on the living Squilla are so interesting 

 that we cannot forbear quoting them. 



The Squilla 1 kept alive in a basin of sea-water for two days, 

 during which time I had a fair opportunity of observing its activity 

 and peculiar habits. It sported about, and after a first approach, 

 exhibited a boldness rather unexpected. When first alarmed, it 

 sprang backward, with great velocity ; after which, it placed itself in 

 a menacing attitude, which would rather have excited a fear of 

 exposing the hand to it. The prominent appearance of the eves, 

 their brilliancy and attentive watching, and the feeling power of the 

 long antennae, evinced quick apprehension and instinct. I brought 

 a silver tea-spoon near them, which was struck out of my hand with 

 a suddenness and force comparable to an electric shock. This blow 



