PTINIHAE 227 



Sub-Family III.— B0STK1CIIINJ5. 



The insects of this sub-family are eloTigate iu furiii; the head 

 is usually deflexed, and protected by the thorax, which is then 

 hood-like in form ; in one tribe, Psoini, it is prominent, and not 

 covered. The mentum is usually small, but in Psoini is large and 

 transverse. The antenna} are distant, and inserted immediately 

 in front of the eyes, upon, or under the frontal margin, and the 

 three outer joints are always larger. The eyes are small, convex, 

 rounded, and distant from the prothorax. The pronotum is not 

 separated from the flanks by a marginal line, except in the first 

 tribe. The anterior coxa3 are large, globose or sub-conical; the 

 hind coxas are not sulcate behind, and project at the inner part; 

 the spurs of the middle and hind tibiae are distinct, and the ante- 

 rior tibiifi are terminated by one long spur, and usually serrate; 

 the troclianters are short; the first joint of the tarsi is very short, 

 sometimes obsolete ; the fifth joint is long, with simple claws. 

 The first ventral segment is but slightly longer than the second. 



Three tribes are indicated : — 



Thorax with distinct lateral margin. Exi)Ecato.m;ni. 

 Thorax without lateral margin ; 



Head covered by prothorax ; anterior coxse contiguous. BosTUicniNr. 



Head prominent ; anterior coxje distant. P.soiiU, 



Tril.<> I.— EXDECATOMIIVI. 



The genus Endecatomus, placed by previous authors in the 

 family Cioidaj, seems, for reasons indicated elsewhere, to belong 

 rather to the jirescMit, in which it constitutes a distinct tribe. 



The head is covered in part by the prothorax, which is dis- 

 tinctly margined at the sides. The epistoma is separated from 

 tlie front by a very distinct suture; the antenu* are 11-jointed, 

 with a loosely articulated 3-jointed club. The anterior coxa; are 

 prominent, and contiguous; the terminal spur of the anterior 

 tibiaj is large and hooked. 'I'he last joint of the tarsi is very long. 



The species known, EndccatoDnoi rnr/osus and E. reticulatua, 

 are oblong convex blackish-l)rown dull in.sects, covered with in- 

 equalities and small erect brown hairs; they are less than one- 

 fifth of an inch long, and found in fungi. They seem 1o liave )mt 

 little relation to the CioidiP, but to be rather a connecting link 

 between liostrichus and Anobiuiu. 



