504 COLEOPTERA OF NORTH AMERICA. 



very large and transverse, contiguous beneath (Ehininse); 

 antennal grooves very short, and not receiving the scape in 

 Calandrinas, suddenly deflexed under the eyes, and receiving 

 the scape in Cossoninre. 



Prothorax truncate in front, not emarginate beneath, pro- 

 sternum long in front of the coxae, which are usually sepa- 

 rated ; prosternal sutures effaced; the transverse suture 

 between the coxie is wanting m Calandrinie and Cossonina?, 

 bat distinct in Ehininas. 



Mesosternurn triangular, truncate behind, side pieces vary- 

 ing according to genus and tribe; middle coxas separated, 

 cavities rounded. 



Metasteruum usually long, episterna varying in breadth, 

 broader in front, epimera large in some CalandriniTe, small in 

 other genera and sub-families; hind coxse transverse, oval, 

 not attaining the side of the abdomen. 



Elytra without epipleura3 ; ex])osing the pygidium in 

 Calandrinaf!, covering it more or less completely in tlie 

 other sub-families; on the inner surface the elevated fold 

 commences near the base, continues parallel and close to the 

 margin as far as the posterior curvature, where it diverges 

 and becomes obsolete. The space between the ridge and 

 the margin has a pearly lustre, and may possibly serve as 

 a stridulating organ; in the Cossoninas this ridge diverges 

 much less and becomes obsolete sooner. 



Abdomen with five ventral segments, of which the first 

 and second are longer, with the suture nearly obliterated at 

 the middle in Calandrina^, but deep and entire in Khininte; 

 in Cossoninte the}'- are very long, and the suture is eftaced 

 at the middle; the third and fourth segments are short, and 

 the sutures straight and deeply impressed; the fifth is about 

 as long as the third and fourth united, and is rounded be- 

 hind. The dorsal segments are membranous, except tlie last, 

 or pygidium, which is large, nearly perpendicular in Calan- 

 drinoe, obliquely deflexed in the other sub-families; the anal 

 segment of the S is quadrate and retractile in Calandrina^ 

 and Rhininas, broader and less retractile in Cossoninaj, but 

 not contiguous with the pygidium as in Curculionidte and 

 Brenthidse; the lateral edge of the metathorax and of the 

 ventral segments is sharp and fits into the lateral groove of 

 the inner surface of the elytra; in the Cossoninse this edge 

 continues on and around the last ventral, thereby showing 

 a tendency towards the modification finally perfected in the 

 Scolytida?., and of which we have already seen traces in the 

 Brenthidffi. 



