18 
(3) Pidonia ruficollis Say, 1824, Jour. Acad, Phila., vol. Ill, p. 421. 
vibex Newm., 1841, Ent., p. 72. 
var, fragilis Csy., 1913, Mem. on the Coleop., p. 202. 
sphaericollis Say, 1826, Jour. Acad. Phila,, vol. V, p. 280. 
discicollis Dej., 1837, Dej. Cat., p. 383. 
lineicornis Csy., 1913, Mem. on the Coleop., p. 201. 
allecta Newm., 1841, Ent., p. 72. 
laeviceps Csy., 1913, Mem. on the Coleop., p. 266. 
collaris Melsh., in litt. 
paupercula Newm., 1841, Ent., p, 72. 
nitidicollis Horn, I860, Proc. Acad. Phila., p. 570. 
Length 6 to 9 mm. L. ruficollis Say was described in 1824 and L. 
sphaericollis Say in 1826. Say, in his original description of L. spkaeri- 
collis, says that it differs from L. ruficollis chiefly in the colour of the 
prothorax. 
_ Mr. Frank Morris, of Peterborough, Ontario, informs us that the 
individuals with red prothorax are in many cases found mating with those 
with the black prothorax, and that the red prothorax is common when they 
first emerge, turning darker as the season advances, finally becoming black; 
this is also in many cases true of the bicoloured legs. Mr. Morris supplied 
us with intermediate colour forms grading from red to piceus black on the 
prothorax. We have been unable to find satisfactory characters differ- 
entiating these two forms; colour alone is, in our opinion, rarely of specific 
value in this group, especially when every intermediate shade is found in 
the same locality. Our Canadian specimens do not differ from those of 
North Carolina, even in size. The male has the last ventral very deeply 
broadly emarginate. 
We can distinguish vibex Newm. from ruficollis Say only by the 
presence of longitudinal yellow vittse on the elytra, and these, on more than 
one specimen before us, are almost obsolete. On one specimen the vitta 
occurs on one elytron and not on the other. Several individuals of the 
form sphaericollis also show a faint indication of similar vittse. We can, 
therefore, find no justification for separating vibex Newm. from ruficollis Say. 
The single type of H. lineicornis Csy. has the pronotum more strongly 
inflated at the sides than usual, and the antennae with the 3rd and 4th 
segments subequal and shorter than the 5th. We would not separate it 
from ruficollis on the basis of this one specimen. H. laeviceps Csy. is a 
stout female with antennae as long as the body. 
One hundred and thirty-two specimens examined from North Carolina, 
Pennsylvania, Massachusetts, Connecticut, New York, Ontario, and 
Quebec. Virginia and Indiana are also cited in literature. 
Type locality of L. ruficollis Say: Kentucky. 
Type locality of L. sphaericollis Say: Salem, Mass. 
Type locality of L, vibex Newm.: Trenton Falls, N.Y. 
(4) Pidonia straussi Webb., 1908, Proc. Ent. Soc. Wash., vol. IX, p. 41. 
This species has the prothorax red and the elytral markings like the 
vibex colour form of ruficollis Say. It differs in the smaller size, stouter 
form, and very much coarser elytral punctation. One specimen before us, 
probably this species, has the prothorax very dark red, almost black. 
Six specimens in the type series have been studied. 
Type locality: Tryon, North Carolina. 
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