742 Coleopterological Notices, VI. 



translucent plate. The genital segment is moderate in size, 

 smooth, polished, even and pale in color, with the apex trans- 

 versely truncate. The other organs are not visible in the tj-pe. 



AM'BLYDERIJS Laf. 



The American species referred to this genus apparentl}^ differ 

 in no essential particular from the North African t3q:)es of La- 

 Ferte, the tubercles along the crest of the subapical declivity of 

 the pronotum being however always inconspicuous. Amblyderus 

 is without doubt a perfectly valid genus, and will prove to be a 

 tolerably large one in the colder parts of the eastern United 

 States and in the true Pacific coast faunal region, where its mem- 

 bers constitute one of the most characteristic elements of the sea- 

 beach population. 



The eight species here deemed worthy of description may be 

 recognized as follows : — 



Species of the Pacific Coast; elongate-oval, very convex, densely clothed with 

 short coarse decumbent pubescence; tubercles and punctures of the prono- 

 tum indiscriminately intermingled and apparently mutually indepen- 

 dent. 

 Larger species, not under 3 nnn. in length. 



Elytra Ijlack, rarely dark brown, the head and prothorax paler..!. olbesilS 

 Elytra and entire body pale luteous-white, the integuments translucent; 



elytra shorter and more attenuate near the apex 2. al1)icaiiS 



Smaller species, always distinctly less than 3 mm. in length. 



Stouter, the head very small, scarcely more than two-thirds as wide as 



the prothorax 3. parviceps 



Kather slender, the bead relatively larger, about five-sixths as wide as the 



prothorax 4. gracileiitiis 



Species of the Great Lakes and Atlantic Coast; tubercles of the pronotum 



situated each immediately before a setigerous puncture, the punctures and 



tubercles evidently mutually connected. 



Antennse shorter, stouter and submoniliform except toward base; vestiture 



rather sparse and somewhat readily renu)val)le. 



Elytral punctures rather small, sparse and not very strong but abruptly 



defined 5. graiilllaris 



Elytral punctures coarse, much closer and impressed ; elytra shorter ; pro- 

 thorax much more transverse 6. pillictig^er 



Antennte long and slender, gradually and more or less feebly stouter to- 

 ward apex ; vestiture finer and closer ; body more oval and convex, the 

 integuments pale. 



Elytra two-thii'ds longer than wide. Lake Superior 7. pallens 



Elytra much shorter and more opaque, scarcely one-half longer than 

 wide. Atlantic Coast 8. areiiariii^ 



