140 COLEOPTERA OF NORTH AMERICA. 



Group III.— Melolonthee. 



Large species, frequently ornamented with spots or stripes of 

 squamiform hair, and distinguished by the broad side pieces of the 

 ruetathorax, the epimera of which are large. The fifth ventral 

 segment and the propygidium are connate by an angulated suture, 

 the spiracle is placed exactly at the angle ; the thorax has no an- 

 terior marginal line. 



The club of the antenna? of Polyphylla assumes an enormous 

 development in the male, and consists of six joints ; in the female 

 it is smaller. 



Two genera are in our fauna, both having a spur on the ante- 

 rior tibia? ; Polyphylla has universal distribution, Thyce is found 

 in New Mexico. 



Antenna with the third joint elongated, club many -jointed. Polyphylla. 

 Antennae with the third joint not elongated ; chib ( f ) small, 3-jointed. 



Thyce, 



Sub-Tribe 8. — Macrophylliiii. 



The genera of this sub-tribe were known only from Africa, 

 Australia, and Polynesia, until the discovery of Phobetus Lee, a 

 Californian genus, allied, apparently, to the South African Trys- 

 sus Er., the characters of which are very indefinitely made known ; 

 but, from the difference of locality, the two genera cannot be sup- 

 posed to be identical. 



The only character by which this sub-tribe is distinguished 

 from the preceding is that the ventral segments are not connate. 

 The anterior coxa? are a little more prominent, and the side pieces 

 of the metathorax are equally wide. 



The generic characters of Phobetus are : antenna? with the club 

 of the male 3-jointed, as long as the rest of the antenna; labrum 

 transverse, concave, somewhat emarginate ; prothorax margined 

 in front, and fringed with membrane ; claws with a broad tooth 

 near the tip, and an indistinct one near the base. 



The species are robust in form, nearly seven-tenths of an inch 

 long, with the margins of the thorax and body, and the whole of 

 the breast, covered with very long hair ; the elytra are glabrous, 

 nearly smooth, with a deep sutural stria. 



In Phobetus comatus the anterior part of the thorax is clothed 

 with long hairs, and the antenna? are 9-joiuted; in P. testaceus 



