2 University of Michigan 



while the common arid region forms of the Tenebrionidae are 

 nearly lacking. 



For a detailed account of the region reference should be 

 made to "Occasional Papers of the IMuseum of Zoology,"" 

 Xo. 8. 



The writer wishes to express his indebtedness to Mr. H. 

 C. Fall and Mr. J. D. Sherman for the determination of cer- 

 tain of the forms. 



List of Species. 



dytiscidae. 



Bidessiis affinis Say. — Collected in pond west of the bridge 

 near Moline Canyon, July 22. This species has been taken 

 at Fort Davis, Texas. 



Coelanihits hyciropiciis Lee. — Specimens of this species were 

 collected among weeds in Maggie Creek, July 11. 



Dcronectcs griscostriatus DeG. — This species was found in 

 a series of ponds along Susan Creek, July 12. 



Agabiis liigens Lee. — Specimens of a form very near to this 

 species were taken on the Carlin Peaks, July 24. 



Rhantns hinotatus Harr. — This species was taken in the 

 pond west of the bridge near Moline Canyon, July 22. 



HVDROPHILIDAE. 



Helophorns linearis Lee. — -This species was taken with the 

 preceding one. 



Tropisternus limbalis Lee. — This form was taken simul- 

 taneously with the preceding. 



