PTKKOSTIGIILS. 00 



Ajjical joint of palpi cylindrical, truncate. Scntelliini 

 very short ; insect apterous. [Steropus, Meg.] 



A A. Third interstice of elytra Avith one im- 

 pression. 

 Ijlack. Thorax l)roader than lono;, rounded, bnse witli a 

 deep round depression on each side, containing two feelile 

 longitudinal striae ; elytra long ovate, rather convex. Fe- 

 mora either black or red. In the male the last ventral 

 segment of the abdomen has at the apex a large depression, 

 and in the middle a short transverse ridge. L. 7 — 8 1. 

 Connnon. F. madidus, Fab. 



M B. Third interstice of elytra with three 

 impressions. 

 Black. Tliorax much broader than long, rounded, basal 

 depressions moderately deep, without longitudinal striae ; 

 elytra ovate, rather convex. In the male the penultimate 

 ventral segment of the abdomen has a large tooth at apex, 

 the last segment has a shallower de})ression. L. 5| 1. Not 

 uncommon. P. aethiops, Panz. 



2. Posterior angles of thorax and generally also 

 shoulders of elytra sharp. 

 Tooth of mentum distinctly emarginate, with sharp 

 points ; insect apterous ; posterior tarsi in general only 

 indistinctly furrowed on outer-side ; anterior tarsi of male 

 strongly dilated ; basal border of elytra not forming a tooth 

 at shoulder ; third interstice with two or more impressions, 

 impressions also frequently in the fifth and seventh inter- 

 stices, short stria often indistinct and usually placed near 

 scutellum. [Fterostichus, Bon.] 



Black. Thorax broader than long, heart-shaped, poste- 

 rior angles right angles, base with a deep, smooth, longitu- 

 dinal impression, and a short, less distinct one (often 

 effaced) on each side ; elytra oblong-ovate, rather flat, with 

 deep, smooth striae, third interstice with three impressions. 

 L. 6 — 8 1. Not very common. 



P. pariimpunctatus, Germ. 



B. Margin of elytra with two striae (at least behind) out- 

 ward from the eighth stria; episterna of metathorax 

 short ; prosternal process not bordered. 

 Tarsi bare and smooth aT)0ve ; first joint of posterior 



tarsi furrowed ; third joint of antennae bare ; thorax as 



