BYRRHID.E 19 



surface short, sparser and less variegated; pronotum with the punc- 

 tures not quite so small and more separated; scutellum wider than 

 long, triangular, with rounded sides, finely, densely punctate but 

 denuded in the type; elytra similar but shorter, scarcely visibly 

 longer than wide, very minutely, closely punctate, the narrower 

 intervals Hat and more opaque, the wider very feebly convex, the 

 striae laterally not. finely and visibly punctate as in altern<itus but 

 almost impunctate. Length 4 8 mm.; width 3.2 mm. Newfound- 

 land (Codroy, Little River) nigrans n. sp 



Nigrans is founded upon a single specimen, so completely denuded 

 that only very few short hairs remain and these only on certain parts 

 of the elytra, but it differs from alternatus or any of its subspecies 

 very decisively in the form of the scutellum, which is longer and 

 more acute in that species, and in the form of the lower margin of 

 the elytra basally, this being strongly arcuate and more protuberant 

 in nigrans; it also differs in its shorter form, stronger and less dense 

 pronotal punctures and much less punctate legs. 



Byrrhus Linne. 



This is the largest genus of the family and in the European fauna 

 consists of two sections, one in which the body is more narrowly oval 

 and the other in which it becomes very broadly oval, larger in size, 

 more roughly sculptured as a rule and with rather longer antennae- 

 named Seminolus by Mulsant and Rey. The first section, or 

 normal Byrrhus, is very abundant throughout the colder parts of 

 North America, but Seminolus has not thus far occurred here. The 

 numerous species form a difficult study, more because of imperfect 

 condition of the specimens than for any other reason, the vestiture 

 being readily removable in many cases, but especially because it is 

 liable to be damaged or obscured by exuded grease. In addition 

 to this, decided structural differences are almost wanting, the specific 

 criteria consisting for the most part of a limited though recognizable 

 diversity in size and outline or in the arrangement of the vestiture 

 and ornamentation. It is for these reasons that the greater member 

 of described European species are now listed as varieties of a com- 

 paratively few more pronounced types. In cases of doubt I have 

 placed some of our own forms in that category provisionally. The 

 majority of the American species conform in general features of 

 structure and ornamentation with the arietinus type of the palae- 

 arctic fauna, though we have also a few peculiar types such as 



