246 COLEOPTERA OP NORTH AMERICA. 



but slender in the male, witli cue small sharp tooth and some 

 small denticles on the outer face; the spurs of the hind tibite are 

 acute in the male, obtuse in the female ; the tarsi are long and 

 slender in the male, but shorter and stouter in the female ; the 

 onychium is liarrow, and bears two long bristles, as in Lucanidte. 



We have been very much at a loss where to place this curious 

 insect. The joints of the club of the antennae do not appear to 

 be capable of being brought into absolute contact, as in other 

 Scaraba;idte, and the club therefore appears pectinate. It was, 

 therefore, reasonable to consider it as allied to the European 

 ^Esalus, among the Lucanidse, which genus it resembles some- 

 what in form ; but the small size of the oral organs, and the tri- 

 angular mentum, have induced us rather to place it as a tribe of 

 the Laparostict Scarabaeidaj, and the position here given it well 

 corresponds both with its external form and Melolonthinc se.xual 

 characters. 



Major Parry and Mr. Deyrolle arc inclined to place Nicagus 

 in the family Lucanidie, as an ally of the New Zealand Mitophyl- 

 lus. It is figured, with some details of structure, in Trans. Ent. 

 Soc. London, 1813, pi. v. fig. 8: on p. 345 of the same volume, 

 may be found its complete bibliography. Mr. Westwood ex- 

 pressed the opinion (ibid. 1870, ix.) that it was not a Lucanide, 

 but was doul:)tful to what tribe of Scaraba^idoB it belongs. On 

 reviewing the subject, we adhere to the opinion expressed in the 

 first edition of this work, that it represents a district tribe near 

 Trogini. Observations of its habits arc in accordance^with this 

 view, since it has been found at Gloucester, N. J., near Philadel- 

 phia, flying near the ground, in the vicinity of the heaps of putrid 

 Unios drawn up in the nets of the fishermen. 



Tribe IX.— TROGIIVI. 



Mandibles and labrum corneous, prominent ; antennas 9- or 

 10-jointcd, club 3-jointed ; anterior coxae rounded, subconical, 

 prominent; middle coxte nearly round, not oblique, contiguous; 

 epimera of the metathorax covered ; epimera of the mesolhorax 

 widely separated from the coxae by the sternum; ventral segments 

 five, not connate ; abdomen covered by the elytra ; tarsi with 

 moderate claws, but no onychium. 



The insects of this tribe are oblong, convex species, living in 

 dried decomposing animal matter. The feet are scarcely fossorial 



