H. C. FALL. 55 



The species of the mammillatus group known to me may be tabu- 

 lated as follows ; 



Vestiture of upper surface thickly set throughout with narrow erect scales; 

 middle and hind femora carinate exteriorly; ventral tubercles feeble. 



horrid US. 



Vestiture of upper surface without erect scales except in small isolated groups or 

 tufts in certain species; femora not carinate; ventral tubercles 

 stj'ong 2. 



2. Prothorax and elytra with numerous conspicuous tuberculiform prominences, 



either of the derm or of the scaly vestiture; second ventral segment 



quadrituberculate quadridens. 



Prothorax never in the least tuberculate, elytra feebly so in certain species; 

 second ventral segment bituberculate 3. 



3. Beak more slender, nearly smooth beyond the antennal foveas, the punctures 



very minute and remote throughout; antennal club very slender and 

 gradually formed ; interocular space narrower, i to j^ the width of the 

 eye; elytra witii two more or less evident transverse rows of promi- 

 nences, formed of groups of more erect scales 4. 



Beak shorter and stouter, coarsely numerously punctate from base to apex, 

 especially at sides, tiie median line smoother; antennal club wider 

 and more abruptly formed; interocular space relatively wide, two- 

 fifths to one-third the width of the eye; elytra devoid of elevated 

 tufts or groups of scales, except feebly in mammillatus 5. 



4. Form more slender and parallel, size smaller (2.3 — 3mm), apical truncature of 



the elyti'a subequal to half the width of the thorax at base. 



jalropliae. 

 Form stouter and more rhomboidal ; size larger (4 mm), apical truncature of 

 elytra distinctly narrower than half the basal width of the thorax. 



filicoruis. 



5. Prothorax with a large and conspicuous subquadrate patch of whitish scales 



at the hind angles; elytral prominences always evident (at least the 

 anterior series) though frequently ill-defined ; form stout. 



Ill am in illaf ns. 

 Prothorax without conspicuous white patch at hind angles; elytral promi- 

 nences feeble in princeps, otherwise completely wanting 6. 



6. Antennal funicle moderately, terminal joints of tarsi densely, albo-squamose. 



princeps. 

 Antennal funicle and terminal joints of tarsi with fine sparse blackish pubes- 

 cence 7. 



7. First funicular joint subequal in length to the second ; scales of upper sur- 



face in great part white, two basal thoracic spots and a small common 



sutural spot at the middle of the elytra, dark littoralis. 



First funicular joint distinctly longer than the second ; elytra each with a 

 large median sublimate or parabolic spot not reaching the suture, dark 

 brown, the scaly vestiture otherwise whitish and pale brown. 



inediinotus. 



TRANS. AM. ENT. SOC. XXXII. DECEMBEE, 1905. 



