206 
Fore femora of male unarmed, hind femora with immense spine nearly half as 
long as tibia; female fore femora unarmed, hind femora with small but 
usually evident spine; jugal spines 4; color paler and size slightly less than 
I METAS. 1 Ee ee a ER ee ae Oe ee eis eee aioe Bere Roto pusillus. 
AMNESTUS SPINIFRONS Say 
Cydnus spinifrons Say, Jour. Acad. Nat. Sci. Phil., Vol. 4, p. 316. 1825. 
United States, west to Colorado and Texas (V. D.), Long Island 
(Olsen). Taken by us in central and northern Illinois from March to 
June 28, and also in November. 
: AMNESTUS PALLIDUS Zimmer 
Annectus [lapsus] pallidus Zimmer, Can. Ent., Vol. 42, p. 166. 1910. 
Described from Kansas as Annectus (!) pallidus. In our collections 
from Algonquin (N. Ill.); Havana, Bloomington, Normal, Champaign 
and Urbana (C. Ill.) ; Centralia and Anna (S. Ill.). Dates from April 18 
to June 19, and October 3 and 5 and December 4. Apparently the same 
species was taken in large numbers at a lamp in Fort Brown, Brownsville, 
Tex., in June. , 
AMNESTUS PUSILLUS Uhl. 
Amnestus pusillus Uhler, Bul. U. S. Geol. and Geogr. Surv. Terr., Vol. 1, 
No. 5, sec. ser., p. 278. 
Common in the eastern United States, west to Kansas and Iowa, and 
also listed from Lower California and Trinidad (V.D.). The northern- 
most records are New Hampshire, New York, Indiana, and lowa. It 
does not appear in our collections from northern Illinois, but has been 
taken at lights, and otherwise, in the central and southern parts of the 
state. It seems to occur later in summer than the other two species, the 
dates running from May 3 to August 20; also December 4. 
The comb teeth of the head margin are paler and longer than those 
of pallidus, and the pronotal transverse impression is deeper than in that 
species. [A male taken at Urbana, August 20, 1914, has the spine on hind 
femur about as long as the femoral diameter. | 
Subfamily THY REOCORINAE * 
The negro-bugs are plentiful and sometimes cause serious injury to 
vegetation. Their oval to circular form, very large scutellum, black color, 
and beetle-like appearance make them readily identifiable in the field. The 
species are numerous and require considerable care in their separation. 
Listed under the name Thyreocoris in Van Duzee’s Catalogue are 
several well-marked groups® which I consider are entitled to distinct 
generic rank. I have before me the European species scarabaeoides Linne, 
the genotype of Thyreocoris. There is no described -American species 
that agrees with it in certain characters which appear to me as of generic 
importance in this family. I have drawn up a synopsis of the differentiat- 
[* The following treatment of this subfamily is entirely by the editor.] 
