24 BULLETIN 276^ V. S. DEPAETMENT OF AGEICULTURE. 
Antennx — Continued. 
ooniiciGS; 
Cauda 
Number 
sensoria on 
segment 
III. 
Cornicles. 
Cauda, 
Number 
sensoria on 
segment 
III. 
Mm. 
Mm. 
Mm. 
Mm. 
0.556 
0.348 
13 
0.697 
12 
.556 
16 
.749 
0.383 
14 
.574 
.313 
12 
.749 
12 
.591 
13 
.678 
.400 
14 
.697 
.4i7 
15 
.697 
11 
COMPARISON WITH THE EUROPEAN PISI, 
After carefully comparing what is commonly known as Macrosi- 
fhum destructor or M. pisi in America with, specimens labeled pisij 
or its equivalent, from Russia, Sweden, England, and Italy, kindly 
sent us by Cholodkovsky, Mordwilko, TuUgren, Theobald, and Del 
Guercio, respectively, and with the complete descriptions of Mord- 
wilko (10) and others, we can find no substantial difference and must 
conclude that the species occurring in Europe and America are iden- 
tical. Measurements of European specimens of the wingless and 
winged viviparous, and wingless oviparous females, all taken from 
specimens mounted on slides in balsam, are given in Table I. 
Table I. — Measurements of European specimens of Macrosiphum 
WINGLESS VIVIPAROUS FEMALE. 
Kalt. 
Labeled— 
Macrosiphum pisi Kalt. 
Wye, Kent, England, on 
peas 26-8-'ll. F. V. 
Theobald 
Siphonophora ulmarise 
(=S. pisi Kalt.) Firenze, 
Italy, on Pisum sativum 
8-6-1908. G. Del Guercio. 
Do 
Do. 
Do. 
Macrosiphum u 1 m a r i ae 
(=M. pisi Kalt.). On Pi- 
sum arvense. Sweden. 
A. Tullgren 
Siphonophora pisi Kalt. 
Pisum sativum, Esth- 
land (Russia). N. Cho- 
lodkovsky 
Macrosiphum pisi Kalt. On 
Pisum sativum 1/14 VllI 
'09. Gouvern, Pskow, 
Russia. A. Mordwilko. 
Received from N. Cho- 
lodkovsky 
Do 
Antennae. 
Mm. 
0. 226 
.226 
Mm. 
0. 122 
.122 
.104 
.113 
.113 
Mm. 
1.165 
1. 165 
1. 234 
1. 304 
1. 330 
1.330 
(-) 
L 286 
1.356 
1. 373 
1.130 
1.208 
1.165 
1. 14S 
1.286 
1.252 
Mm. 
0.895 
.939 
1.009 
1.078 
1.095 
(') 
1.086 
1.069 
1.095 
.939 
.948 
1.078 
1.043 
Mm. 
0. 817 
.835 
,878 
(2) 
.887 
869 
.965 
.974 
Mm. 
0. 313 
.304 
278 
.304 
.330 
Mm. 
1. 217 
1 1. 304 
1 1. 304 
1.338 
1. 156 
1. 1S2 
1.043 
1.043 
1.321 
1.286 
Length. 
Mm. 
0. 852 
.817 
L 130 
1. 130 
Mm. 
>0. 748 
.739 
1. 173|; 
l-3-«j}.782 
1. 078i\ 
1. 113 / 
1.2001 
800 
1.252' 
1. 252 
.765 
,835\ 
,835/- 
,974 
,974 
. 783 
Wiags. 
Mm.. 
T3 
Mm. 
1 Tip shriveled. 
2 Mo asurements of segments III, IV, and V combined, 3.355 mm. 
