Mar. 6,1916 
Identity of Eriosoma pyri 
1119 
Prociphilus poschingeri (Holzner) (fig. 1, B, M). 
Placed usually as a synonym of bumulae Schrank, this form as represented by our 
specimens shows some differences. The insects are considerably smaller and the 
dorsal wax plates of the thorax are not triangular and close together as are those of 
bumulae , but are considerably separated and oval in outline. Measurements of 
antennal segments: III, 0.496 mm.; IV, 0.246 mm.; V, 0.246 mm.; VI, base 0.224 
mm., unguis 0.048 mm. 
Prociphilus tessellatus (Fitch) (fig. 1, K, T). 
The antennae of tessellatus are hardly typical for this genus. The species seems, 
however, to fit here as well as anywhere. The sensoria on the antennae are very broad 
for the genus and the shape of the segments is not typical. The dorsal wax pores 
are, however, quite normal. They are somewhat triangular in shape and are some¬ 
what smaller than those of venafuscus. In many specimens each is armed with a 
small hair. Measurements of antennal segments: III, 0.4 mm.; IV, 0.171 mm.; 
V, 0.171 mm.; VI, base 0.197 mm., unguis 0.032 mm. 
Prociphilus venafuscus (Patch) (fig. 1, C, D, 0 ). 
The form described by Dr. Patch 1 is the most typical American species and the 
antennal characters are very similar to those of bumulae Schrank. The clouding of 
the wings met with in venafuscus is present also in our specimens of poschingeri though 
it is not noted in those of bumulae. The dorsal wax plates of the thorax are, in vena¬ 
fuscus , triangular like those of bumulae. They are, however, very much smaller. 
Measurements of .antennal segments: III, 0.56 mm.; IV, 0.288 mm.; V, 0.288 mm.; 
VI, base 0.224 mm., unguis 0.049 mm - 
Prociphilus xylostei (De Geer) (fig. 1, F, N). 
Specimens of this species are much smaller than those of bumulae or even those of 
venafuscus. The antennal characters are very similar to those of venafuscus. The 
dorsal wax plates of the thorax are, however, of quite different shape in the two species, 
although they are almost equal in size. Measurements of antennal segments: III, 
0.48 mm.; IV, 0.24 mm.; V, 0.24 mm.; VI, base 0.197 mm., unguis 0.048 mm. 
The average number of sensoria on the antennae of the species figured is shown in 
the illustration. The number varies somewhat in different individuals. 
1 Patch, Edith M. Aphid pests of Maine. In Maine Agr. Exp. Sta. Bui. 202, p. 174. 1912- 
