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CALIFORNIA ACADEMY OF SCIENCES. 



Hydroporus latebrosus Lee. 

 Coptotomus interrogatus Fab. 

 Hydrotrupes palpalis Sharp. 

 liybiosoma regularis Lee. 

 Agabinus glabrellus Mots. 

 Agabus lugens Lee. 



lineellus Lee. 



morosus Lee. 



obsoletus Lee. 



lecontei Cr. 



Gyrinus plicifer Lee. 

 consobrinus Lee. 



Bhantus binotatus Harr. 



anisonychus Cr. 

 Corymbites strigatus Lee. 

 Eretes sticticus Linn. 

 Dytiscus marginicollis Lee. 

 Thermonectes basilaris var. inter- 

 medius Cr. 



marmoratus Hope. 

 Cybister ellipticus Lee. 



explanatus Lee. 



GYRINID^E. 



Gyretes sinuatus Lee. 



HYDROPHILID^. 



Helophorus obscurus Lee. 

 Hydrochus variolatus Lee. 



vagus Lee. 



sp. nov. 

 Ochthebius rectus Lee. 



costipennis sp. nov. 



puncticollis Lee. 



discretus Lee. 



nitidus Lee. 



interruptus Lee. 



lineatus Lee. 



sculptus Lee. 



holmbergi M'dkl. 

 Hydreena pennsylvanica Kies. 

 Hydrophilus triangularis Say. 



insularis Lap. 

 Tropisternus limbalis Lee. 



californicus Lee. 



salsamentus sp. nov. 



ellipticus Lee. 

 Hydrocharis glaucus Lee. 



obtusatus Say. 

 Berosus punctatissimus Lee. 



miles Lee. 



salinus sp. nov. 



subsignatus Lee. 



Berosus infuscatus Lee. 



rugulosus Horn. 

 Chsetarthria nigrella Lee. 



minor sp. nov. 



pallida Lee . 



Limnebius piceus Horn. 

 Laccobius ellipticus Lee. 

 Philydrus carinatus Lee. 



nebulosus Say. 



californicus Horn. 



diffusus Lee. 



Helochares normatus Lee. 

 Cymbiodyta punctatostriata Horn. 



dorsalis Mots. 

 Hydrobius fuscipes Linn. 

 Creniphilus subcupreus Say. 



elegans sp. nov. 



rufiventris Horn. 



infuscatus Mots. 

 Dactylosternum cacti Lee. 

 Cercyon fimbriatus Mann. 



luniger Mann. 



fulvipennis Mann. 



nigriceps Marsh. 



lugubris PayJc. 

 Megasternum posticatum Mann. 



