No. 484] ATTACHED YOUNG OF CRAYFISH 269 



that material and Souheiran stated that the yoiin^ of an Astacus 

 ate the egg cases and larval skins. 



The third stage larvie stayed near the mother some ten days or 

 more, often, when disturbed, climhiiiu- on oih- aiioili(M- and crowil- 

 ing under and upon the motlici'. hut aftci' iliai iluy wciv (|iiitc 

 independent and seemed to hiwr no associntioii wiili die moilicr 

 though kept in the same small a<|iiariiim. 



Walking and swimmino- the yoimu' sought food o\(t the KoUom 

 of the aquarium and in a day cleaned otV all the l.rown d.>|.o>it 

 from a spray of Myriophyllmn and when another piece was uiven 

 them ravenously set ahout teai'in,u' oil' and eatino- the hactei'ial 

 slime and algal growths. When given Chai-a they >ei;'.ed nii 

 internode with their month j)ai-ts and ])tished it with iheir feet 

 somewhat as a dog gnaws a bone, but when j)ieees of internode 

 were cut off for them they seized them by one end and walked 

 about suc;king the contents out. Such a larva holding its head 

 high and supporting a stick longer than its body, held by its 

 mouth parts straight out in front of it, ludicrously suggested the 

 enjoyment of a huge stick of candy. Animal food in the shape of a 

 dead comrade was eagerly sei:;ed and {Milled to ])ieees and a small 

 earthworm was eaten tip m a few lioiirs. 



Living thus, at a temperature of .v") the yonnu' were very 



water. After two weeks some molted without nmeh change 

 <.f si/e but by duly 3rd some were 13 to b") mm. long and the only 

 survivor. July l.")th, 18 or 19 mm. long. 



From the above account it appears that the voting of (Uimharns 

 clarkii and (Uimbarus diogcnc.s associate with the jtarent in the 

 first and second stages and in part of the third and this sort of 

 family life is aided both by special recurved tip^ on tlu' chehe and 

 by a peculiar teUcn threa i; an. I a-^ thi^ i^ irue aU.. in C. nvmis a. 



gen.'ral fact Inr all ^pr, ir^ the^c tu.. umna Mnn .Al.r all ilieM> 

 ci-ayhsh show in the voun- .tniclural .•liara.-irr. and !.al.il> that 

 make them unfit for "free life like that (.f their niarine relative.. 



\vith the mother with whom they live as in a kind of elementary 

 family. 



