MONOMMIDAE. 393 



This family is represeuted iu our fauna by five 8|)(.'cies irom 

 the Atlantic States; they are found under bark and on leaves- 

 they belong- to a tribe, Statirini, to be distinguished from the 

 genuine Lagriini by the sixth ventral segment being visible, and 

 the last joint of the antennae elongated. Two genera are indi- 

 cated : — 



Head scarct^ly constricted beliiiid (ch-tra not striate). Arthromacra. 



Head strongly constricted behind (elytra striate). Statira. 



To Arthromacra belongs only Lagria senea Say {Arlhrom. 

 donacioides Kirby). 



There is absolutely nothing in the preceding formula which 

 can be relied on as distinguishing this family from tlie Tenebrio- 

 nidae, except the prominent anterioi" coxae, and the dilated penul- 

 timate joint of the tarsi ; the larvte are nevertheless very different, 

 and it is chiefly owing to a knowledge of that fact that the two 

 families are retained as distinct. 



Fam. LXIII.— MONOMMIDAE. 



Mentum moderate in size, somewhat rounded, supported 

 by a broad gular jirocess; gular fissures narrow; ligula cor- 

 neous, somewhat prominent behind the mentum ; labial palpi 

 3-jointed. 



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

 last joint truncate. 



Head horizontal, prominent, received in the thorax as f\ir 

 as the eyes, which are large, transverse, and strongly granu- 

 lated; front flat, rounded anteriorly; labrum short, scarcely 

 prominent; mandibles short, emarginate at tip. 



Antennaj inserted under the frontal margin, received in 

 grooves on the under surface of the prothorax, 11-jointed; 

 last three joints larger, forming an oval flattened club. 



Prothorax gradually narrowed from base to tip, as wide 

 at base as the elytra; lateral suture distinct; Hanks with a 

 deep curved groove from the front to the hind angle for the 

 reception of the antenna3; prostcrnum broad, rounded be- 

 hind, fitting closely to the mesosternum; coxal cavities very 

 small, closed behind by the mesosternum. 



Mes(^sternnm l)road, side pieces not extending to the coxal 

 cavities; metasternum large; side pieces narrow; epimera 

 visible. 



