H. C. FALL. 163 



quite as distinct as in many specimens of sordidus, in fact the 

 two species seem quite closely allied. Chinensis, by its short, 

 thick, cuboidal form, pectinate male antennae, vertical pygi- 

 dium and short intermediate ventral segments is manifestly 

 allied to the species of Group IV. The affinities of quadri- 

 maculatus are probably more nearly with chinensis than any 

 other of our species, but it differs notably in its longer more 

 depressed form, more oblique pygidium and simple male 

 antennae. 



Horn was probably correct in considering biguttelus Sch. 

 a dark colored male of chinensis, simiatus Sch. a form of 

 quadrimaculatzcs, and maculatus Fab. identical with quadri- 

 maculatus ; these names, therefore, should be dropped from 

 our list. Ambiguus Sch. is still unknown to us, and its posi- 

 tion in this group, as Horn remarks, is not quite certain, 

 though very probable because of the comparison with quadri- 

 maculaiiis. Our species may be briefly characterized as 

 follows : 



Front carinate, prothoracic lobe with two short confluent 

 spots of white pubescence, one on either side of the median 

 groove, elytra varicolored, fourth and fifth elytral striae 

 shortest, femoral teeth subequal in length. 



Form short and thick, antennas of & pectinate, pygidium perpendicu- 

 lar, white hairs of thoracic lobe with ivory lustre (Cosmo- 

 politan species) ohineiisis Linn. 



Form more elongate and depressed, antennas of c? not pectinate, pygi- 

 dium more or less oblique at base, white hairs of thoracic 

 lobe not distinctly eburneous. (Southern States). 



quadrimaculatus Fab. 



Similar to quadrimaculatus, but more than twice as large. (Louis- 

 iana.) ambiguus Sch. 



Group IV. 

 The species of this group are strongly characterized by 

 their robust quadrate form, pectinate or flabellate male an- 

 tennae, very large eyes which are almost approximate in the 

 male, narrowly separated in the female ; perpendicular pygi- 

 dium, ventral segments 2-4 very short, together not or 

 scarcely longer than the first segment behind the coxal plates ; 

 fourth and fifth elytral striae short, attaining about the apical 



TRANS. AM. EXT. SOC, XXXVI. JULY, 1910. 



