LAGRIIDAE. 245 



hind angles of the thorax prolonged backwards, the sixth ventral 

 segment is visible in both sexes, and in the male is very deeply 

 excavated, so as to form two long, flattened, curved processes ; 

 the fifth segment is emarginate in the same sex ; the joints 1 — 4 of 

 the anterior tarsi of the male are moderately dilated, and the fifth 

 is elongated, flattened, and twisted, so as to be much deformed, 

 with the claws larger than the female. The mandibles are not 

 truncate or emarginafc at tip, and the tarsi are not at all lobed. 

 A second species ( - 38 — -41 unc. long), from the Southern States, 

 only differs from A. fuscipes by the thorax being less sinuate at 

 base, with the hind angles scarcely prolonged. I have named it 

 A. luteipes. 



Fam. L.— LAGRIIDAE. 



Mentum transverse, trapezoidal, wider in front, supported 

 on a distinct gular process ; ligula prominent ; palpi 3-jointed. 



Maxillae with two flattened, ciliated lobes ; palpi 4-jointed, 

 moderate in size. 



Head prominent, horizontal, inserted into the thorax, more 

 or less constricted behind the eyes, which are transverse, 

 emarginate, and not finely granulated ; clypeus subcoria- 

 ceous; labrum prominent; mandibles short. 



Antennas 11-jointed, nearly filiform, inserted under very 

 small oblique frontal ridges. 



Prothorax narrower than the base of the elytra, subcylin- 

 drical, with the lateral suture obliterated ; anterior coxal 

 cavities closed behind, and nearly confluent. 



Mesosternum moderately long, side pieces attaining the 

 coxal cavities ; metasternum long, side pieces narrow ; epi- 

 mera not visible. 



Elytra rounded at tip, covering the abdomen ; epipleurae 

 narrow ; wings perfect. 



Abdomen with five free ventral segments, the anterior 

 four of which appear to be more closely connected ; fifth 

 rounded at tip, sixth sometimes visible. 



Legs slender; anterior coxae conical, prominent, without 

 trochantin, separated by a very narrow prosternum ; middle 

 coxae separated, with distinct trochantin ; hind coxae trans- 

 verse; tibial spurs obsolete; front and middle tarsi 5-jointed ; 

 hind tarsi 4-jointed, with the first joint long ; the penultimate 

 joint of all the tarsi (except in one foreign genus) is dilated, 



