22 
NORTH AMERICAN THROSCIDAE 
THROSCTIS Latreille 
The species of this genus in our fauna are as a rule much less 
robust than the species of Aulonothroscus, more finely sculptured 
and paler in color. The antennae exhibit little variation. In 
carinicollis the club is a little broader and more hairy in the male, 
and the eyes are larger in the same sex. Our species with di- 
vided eyes and entire prosternal striae, have in the male the 
elytral margin with a rather conspicuous spreading fringe of pale 
hairs, some vestiges of which almost always remain in the most 
poorly preserved specimens. This character was first observed 
in certain European species about the time of Dr. Horn’s paper. 
In the European fauna all the members of the tribe Throscini 
belong to this genus. In the Wiener Entomologische Zeitung 
(viii, p. 35), Reitter gives a synoptic table of eleven species. 
Our species may be separated as follows: 
1. Eyes entire; head not carinate; prosternal striae entire 1. horni 
Eyes deeply divided; head bicarinate 2 
2. Prosternal striae entire; elytra of cf with fringe of long hairs 3 
Prosternal striae abbreviated; eljdra cf not fringed 6 
3. Pubescence long 4 
Pubescence short and closely appressed 5 
4. Eyes larger, especially in the cf, orbits impressed; cephalic carinae stronger 
and rather more parallel 2. carinicollis 
Eyes smaller, alike in the sexes; size smaller and form narrower. 
5. Form broader, less narrowed behind, interstrial punctures becoming vario- 
1. Throscus horni nom. nov. 
[This name is proposed by Blanchard for the alienus of Horn’s 
Synopsis, which was not the true alienus of Bonvouloir, the latter 
being really the male of constrictor Say. The species was quite 
unknown to Blanchard and he attempts no description. The 
species, according to Horn, “ occurs in the Gulf States.” H. C. F.] 
2. Throscus carinicollis Schaeffer® 
Elongate oval, narrowed behind, dark or reddish brown with a fine, close 
pubescence and coarser hairs intermixed. Head convex, finely, not closely 
punctate, rather strongly bicarinate, the carinae parallel or nearly so in the 
male, feebly divergent above in the female. Antennae in the male with club 
broader, somewhat contractile and equal in length to joints one to eight, in the 
female smaller and only equal in length to joints three to eight. Eyes larger in 
®Bull. Brooklyn Ent. Soc., 1916, p. 63. 
3. chevrolati 
late posteriorly 
6. Pubescence very short and close 
4 . mendaz 
.5. sericeus 
