176 MEMOIRS ON THE COLEOPTERA 



From hydrophiloides Burm., this species differs decisively in 

 many directions, for in hydrophiloides the color is clear brown, 

 with darker head, the front near each eye having a cluster of 

 punctures and the length as published is only 16 mm., all of which 

 characters are widely at variance with rhomboidalis. From the 

 West Indian barbatus, it differs in having the legs perfectly uni- 

 colorous, not with the femora rufescent, as stated by Burmeister of 

 barbatus. Mr. Bates suggests that hydrophiloides and barbatus are 

 the same species, but I feel confident that this opinion is the result 

 of a misconception. 



In the male of rhomboidalis the claw-joint of the anterior tarsi 

 is large and swollen as in Dyscinetus, but the larger claw is different; 

 it is well developed and abruptly bent near the base, but it is not 

 at all split at apex, but arcuately and somewhat obliquely obtusely 

 pointed; its flattened under surface is feebly bicarinulate and, near 

 the apex on the inner side-margin, there is a small obtuse tooth 

 projecting downward, not visible from the upper surface of the claw. 



Group II. 

 Subgenus Chalepides nov. 



Besides alliaceus and fuliginosus, of Burmeister, this subgenus 

 will include the following, which may be regarded as the type: 



Body elongate, subparallel, strongly convex, very smooth and shining, 

 dark castaneous in color, the legs slightly more rufous, the elytra 

 paler brownish-yellow throughout; head notably large, fully two- 

 thirds as wide as the prothorax, the eyes moderate though rather 

 convex; front with rather small but distinct, somewhat close-set 

 punctures, finer and sparse basally; front and basal part of the 

 clypeus flattened, the clypeus with close-set, shallow, arcuate punc- 

 tures throughout, trapezoidal, more than twice as wide as long, 

 broadly sinuato-truncate at apex, with broadly rounded angles; 

 edges evenly and moderately but rather sharply elevated internally; 

 surface strongly declivous toward the angles; suture fine, entire, dis- 

 tinctly sinuate medially; mentum glabrous, setose only along the 

 sides; prothorax three-fourths wider than long, subparallel, with 

 evenly and rather strongly rounded sides, the basal angles only 

 moderately rounded; base nearly transverse, feebly sinuate in the 

 usual position near each side; apical bead entire; punctures sparse, 

 fine but distinct, becoming more conspicuous laterad; scutellum 

 smooth, sharply triangular; elytra (9 ) but little less than one-half 

 longer than wide, slightly wider than the prothorax, circularly 

 rounded in apical two-fifths, the sides parallel and broadly, evenly 



