484 



illl': AMEHICAX NATURALIST 



[Vol. LIII 



6). At this phico, T have captured gerrids by the hun- 

 dreds. I have examined this \)oo\ and the immediate 

 vicinity for two successive seasons and 1 am convinced 

 tliat they breed here from year to year. They undoubt- 

 edly hibernate, in hirge numbers, along the shores of 



this pool. In fact 1 have found a few of them hibernat- 

 ing in interstices where the shore slightly overhangs 

 the water, and also among dead leaves and other vegeta- 

 tion at points from a few inclies 1o tlirec xai'ds away 

 from the pool (Fig. 6). 



Mf'tliorU.—'Y\\Q experiment^ wnv i MTl'i.nM'*! on the 

 Miore (»r tlie i)o..l, whi.-li i< a hn-c n,,,. t'ur ^n.-li a Hiiall 

 hrook. Tlic .lii.HMiHoiK (.r tlii> liodv n\- ualri' are ap- 

 pr..\iirat.'lv :.:> 17 ■ L\:> h'd. Till' ^In-iv. v.licre the 



..xp.-nnirntal uurk waxl i. fiat a.nlil^ H.r!an. i. only 



al\'wihchr. hi.uhrrtliaiithatortlM'XxatrriKiu.i;). IJack 

 of tlii^ flat aiva. a little nion- than liir.M. sai.U auax tVoii; 

 the tliMv 1. a l,i!| with a nin,le,ate --hM,... ()i,!> 



thoM- experiiiuMit^ uiP li,- rnnH.lenMl !,riv that ueiv car 

 rie<l far ...ouuh in evin.v i'ai,-|v <l..|ihitr v.^uW^. Tlie 

 water-^iii.h-.- n^..| in th-.^e .Ain.riiiirnt^ ^^vvr taken 

 directly tVoni the sui ia<'e of the po.,!. Di fiVr.'iit indi- 

 viduals were used in each exiMM-lnient. All thcM' experi- 



