262 Trans. Acad. Sci. of St. Louis. 



Prothorax broader and more transverse, subequal in width to the base of 

 the elytra; infra- lateral carinae of the head distinct and entire 4 



2 — Infra-lateral carinae of the head wholly obsolete except for a short dis- 



tance anteriorly ; neck narrower than in any other genus of the sub- 

 tribe, slightly less than half as wide as the head ; mesosternal process 

 moderately wide, obtuse, somewhat free and not attaining the meta- 

 sternal projection; prosternum before the coxae and posterior part of 

 the mesosternum finely and acutely carinate along the middle; basal 

 joint of the hind tarsi about as long as the next two combined; pro- 

 notal punctures normal, coarser, not asperate. Europe.. *Bolitochara 

 Infra-lateral carinae distinct and entire; neck wider, always more than half 

 as wide as the head 3 



3 — Head strongly narrowed behind the eyes, the neck about two-thirds as 



wide; hypomera shorter, coming far from attaining the anterior limits 

 of the prothorax; mesosternal process only moderately narrow and 

 more obtuse, almost attaining the metasternal projection; basal joint 

 of the hind tarsi not as long as the next two combined; pronotal punc- 

 tures simple and impressed, not asperate. Europe '^Ditropalia 



Head feebly narrowed behind the eyes, the neck very broad; hypomera 

 more elongate, almost attaining the anterior limits of the prothorax ; 

 mesosternal process narrow, subacute and freer at tip, the latter sepa- 

 rated from the metasternal projection by a much greater longitudinal 

 discontinuity; basal joint of the hind tarsi much more elongate, some- 

 times subequal to the next three combined ; pronotal punctures always 

 very fine and granuliform or asperate; eyes similar, moderate in size and 

 prominent. Nearctic Pacific coast regions Stlctalia 



4 — Antennae gradually thicker distally as in the preceding genera; head 



not materially narrowed behind the prominent eyes, the neck very wide; 

 hypomera visible from the sides as in all the other genera of the sub- 

 tribe, attaining the apex of ithe prothorax; sides of the latter feebly 

 rounded and not at all sinuate toward base; antennae short, the outer 

 joints strongly transverse; pronotal punctures minute and asperu- 



late 5 



Antennae not or scarcely thicker externally, the last seven or eight joints 

 forming a loose parallel-sided club; head, hypomera and sculpture 

 similar, tbe infra -lateral carinae unusually acute and very strongly ele- 

 vated; sides of the prothorax very feebly sinuate toward base, the basal 

 angles more distinct 6 



5 — Mesosternal process broad anteriorly, rapidly narrowed, its apex nar- 



rowly rounded or subacute, free and separated from the metasternal 

 projection by a considerable longitudinal discontinuity; basal joint of 

 the hind tarsi scarcely as long as the next two combined. Europe. 



* Phjmatnra 



Mesosternal process longer, narrow and more parallel, free and rounded 



at tip, virtually attaining the apex of the metasternal projection; basal 



joint of the hind tarsi fully as long as the next two combined. Nearctic 



Atlantic regions Silnsida 



6 — Fourth antennal joint small, about as wide as the preceding joints and 



very much smaller than those which follow; intermesocoxal parts nearly 

 as in Bolitochara, the process varying from moderately wide to rather 



