BIOLOGICAL PAPERS. 231 



Size medium; form short, broad fusiform. Head broad; interspace between 

 the eyes almost equal to twice the width of the eye; eyes broad ovoid; an- 

 tennae almost twice the length of the body; palpi with the fifth joint half 

 again as long as the third. Pronotum arched transversely, slighly com- 

 pressed ; anterior border broadly emarginate, posterior truncate, lateral 

 lobes subtruncate. Mesonotum and metanotum very slightly deeper than 

 the pronotum. Abdomen distinctly but moderately compressed, lateral 

 aspects sprinkled with fine granules, cerci short, about one-fourth the 

 length of the posterior femora, subgenital plate deeply and broadly emar- 

 ginate, the lateral portions projecting as obtuse-angulate lobes. Anterior 

 femora about one-sixth longer than the pronotum, anterior inferior margin 

 unarmed or with a single preapical spine; tibine unarmed above. Median 

 femora about equal in length to the anterior pair, armed beneath on the 

 anterior margin with one to four spines, on the posterior margin with five 

 spines. Posterior femora slightly more than three times as long as broad, 

 the superior face bearing a number of short spiniform tubercles, distal two- 

 thirds of the inferior margins with close-set series of short teeth, interven- 

 ing sulcus moderately deep; tibite equal to the femora in length, very 

 slightly bent, armed above with four pairs of spurs and a number of spines 

 of the second grade, below armed apically with two pairs and two single 

 spines, inferior calcaria exceeding the others in length. 



General color of the dorsal surface of the body burnt sienna inclining toward 

 Vandyke brown on the abdomen. Ventral surface and limbs ochraceous. 



Measurements: Length of body, 15 mm. ; length of pronotum, 5.2 mm. ; great- 

 est width of pronotum, 6.5 mm. ; length of posterior femora, 14 mm. 



Family Gryllid^e, 

 Tridactylus apicalis Say. 



Bill Williams Fork, Mohave-Yuma counties, Ariz. ; August, F. II. Snow. 

 One individual. 

 Gryllus pennsylvanicus Burmeister. 



Bill Williams Fork, Mohave-Yuma counties, Ariz. ; August, F. H. Snow. 

 One male. 

 CEcanthus fasciatus Fitch ? 



Bill Williams Fork, Mohave-Yuma counties, Ariz. ; August, F. H. Snow. 

 One female. Some doubt is attached to this identification. 



