478 



THE AMERICAN NATURALIST 



[Vol. XL! 



of cat-tails (Typlia). Tl 

 anywhere, but the hollovA 

 with oak leaves from the surrounding forest trees. 



It is in the typha beds of the upper end of the pond, extending 

 from the shore outward into water of about a meter in depth, tliat 

 the diving l)eetles are commonly found. These beds cover an 

 area of hut little more than a square decameter, but in them we 

 have found twenty-nine species of Dytiscidie, as follows — 

 *Laccophilus viaculosus (iermar JI i/dwponis modcsfus Aube 



LaccophUu^ ptsclaius Aubc Jh/droporus dichrous Melsli. 



Larrnphilns- pro.viniNs Say Ih/hlus nmlusus Aube 



*/)'/Wr.v,s'//.v larusf!-is Sjiy Afjdhu.s .suhfiiwatus Sharp 



liidrssus jla r/rollls Lee. Ai/dhiis d i.sinlrf/ratus Cr. 



Bidrs.sii.s ajjiin's Say lihanliis iiofaius Fabr. 



H'a lamhiis i>injuali.s Fabi-. ( ,i)id>r1,'s .sridptUis Harr. 



(Wlamhii.^ pin>rtafiis Say lli'idafirus piccuH IvCC. 



('aJa,nhus disnar ' I'rilins .v, ml.s'ulcatu.s Aube 



Calambu.s imprc.s.w-pinirlafNs Sell. 



Deronedes caiascopium Say 

 *IIydroporus undulaivs Say 

 Xo other Dytiscida- have beiMi foi 

 that are occasionally cast up on tli 

 that w^e have picked up from ilicdr 



Distribution by Size and Depth of 

 the above list tliat arc niark«Ml w 



