THE PEA APHIS WITH RELATION TO FORAGE CROPS. 
13 
fourth of V, distal half of VI, base and aU o'f filament of VI, which 
parts are black; segment III sometimes, but not always, bewaring a 
small inconspicuous sensorium near its base and the usual sensoria 
at distal end of V and VI 
base. Beak just reaching 
coxa3 of second pair of h^gs. 
L(^gs with femur very pak^ 
gvQcn and s(^mi transpar- 
ent; tibia with basal hah 
pale semitransparent, the 
distal half with a faint 
bro^vnisli tint and the tip 
black; tarsus black. Cor- 
nicles reaching tip of cauda 
(of the four spt^cimens ex- 
amined the cornicles 
n^ached a little beyond th(^ 
tip of Cauda in three speci- 
mens and not quite to the 
tip in the fourth specimen), 
concolorous with body at 
base, becoming paler and 
semitransparent toward Fig. 2.— J/acms/yJmm /jmV Adult stem-mother. Much en- 
the apex, th(^ tip blackish; (^"sinai.) 
cyhndrical and slender; noticeably widened at base and the tip imbri- 
cated. Cauda ensiform and t}T>ical of the genus, and concolorous 
with body. 
Measm-ements from two specimens immediately after placing aUve 
in balsam and before slirinkage occurs: Length of body, 2.63 mm., to 
tip of Cauda, 3," width, 1.45; length of cornicles, 0.74 mm., of cauda, 
0.44. Measurements of antennal segments: 
I. 
II. 
III. 
IV. 
V. 
VI, base. 
VI, fila- 
ment. 
Mm. 
Mm. 
Mm. 
Mm. 
Mm. 
Mm. 
Mm. 
0. 156 
0.069 
0.695 
0.348 
0.469 
0. 235 
0.522 
.156 
.078 
.695 
.348 
.452 
.243 
.539 
.139 
.078 
.626 
. 287 
.400 
.209 
.469 
. r?9 
. 0S7 
.634 
.296 
.400 
.209 
.469 
SUMMER VIVIPAROUS GENERATION. 
First instar, hef ore first molt and about 1 hour old (fig. 3). — (D(\seribed 
from six specimens, Aug. 20-21, 1912.) Head and thoracic segments 
wliitish with a pale gi-eenish tint; remainder of body pah* green 
excepting those segments posterior to and including the segment 
