24 BULLETIN 276, V. S. DEPARTMENT OY AGRICULTURE. 



Antennse — Continued . 



Cornicles, 



Cauda. 



Number 



sensoria on 



segment 



III. 



Cornicles. 



Cauda. 



Number 



sensoria on 



segment 



in. 



Mm. 

 0. 556 

 .556 

 .574 

 .591 

 .697 



Mm. 



0.348 



13 

 16 

 12 

 13 



15 



Mm. 

 0.697 

 .749 

 .749 

 .678 

 .697 



Mm. 



12 

 14 

 12 



0.383 



.313 



.400 



14 



.417 



11 









COMPARISON WITH THE EUROPEAN PISI. 



After carefully comparing what is commonly known as Macrosi- 

 phum destructor or M. pisi in America with specimens labeled pisi, 

 or its equivalent, from Russia, Sweden, England, and Italy, kindly 

 sent us by Cholodkovsky, Mordwilko, Tullgren, 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 pisi Kali. 



WINGLESS VIVIPAROUS FEMALE. 





Antennae. 



Length. 



Wings. 



Labeled — 



f-I 



t— ( 





> 



> 



CO 



n 



> 



CD 



a 



_c3 

 > 



C r- 



- z u 



— t c 



CD 



'5 



u 

 o 

 O 



C3 



"2 

 5 

 o 



cjj 



a 



o 



•3 



Macrosiphum pisi Kalt. 

 Wye, Kent, England, on 

 peas 26-8-'ll. F. V. 

 Theobald 



Mm. 



1 0. 226 

 | .226 



Mm. 



0.122 



.122 



Mm. 



1.165 

 1.165 



1.234 



Mm. 



0.S95 

 .939 



1.009 



Mm. 



0.817 

 .835 



.835 



Mm. 



0.313 

 .304 



.278 



Mm. 

 1.217 



1. 14S 



2 

 2 



5 



Mm. 

 0.852 



Mm . 



}l).74S 



Mm. 



^^m. 



1.1301 713 

 1.130/ •'" 



1. 199 1 ~iq 

 1 L73 j • 73S 

 1,338 1 .782 



| : d}.696 



1.200 J m 



L.252\ -„- 

 1.252? • 







Siphonophora ulmarite 

 (=S. pisi Kalt.) Firenze, 

 Italy, on Pisum sativum 

 8-6-1908. G.Del Guercio. 



Do 





/ .191 



.104 



1. 304 











2 

















Do 



/ .243 

 j .226 



.122 

 .122 



1. 330 

 1. 330 



(') 

 1. 286 



1. 3.56 

 1. 373 



1.130 

 1.208 



1.165 



]. 1 l-. 



1.286 

 L.252 



1.078 



1.095 



( 2 ) 



1.086 



1.069 

 1.095 



.939 



.'.'is 



.835 



.800 



1.078 

 1.043 



.878 

 .869 



( 2 ) 



.SS7 



.878 

 .921 



.869 

 .869 



.800 

 .800 



.965 

 .974 



.34s 

 .34S 

 . 3311 

 .313 



.330 



'1.304 

 1 1.3114 



1.338 

 '1.200 



2 

 3 

 I 

 3 



:; 



5 



3 

 3 



3 

 2 



3 

 3 















[ 







Macrosiphum u 1 m a r i se 

 (=M. pisi Kalt.). On Pi- 

 sum arvense. Sweden. 



1 



.226 

 ' .226 



.113 

 .113 













.304 



.313 



.296 



.313 



l 156 

 1 182 



i ii . 

 L.043 



1.321 

 1.286 





Siphonophora pisi Kalt. 

 Pisum sativum, Esth- 





land (Russia). N. Cho- 



[ 















.835 



I 





Macrosiphum pisi Kalt. On 

 Pisum sativum 1/14 VIII 







1 



.835 











Received from N. Cho- 



/ .226 

 \ .209 



.122 

 .113 



■HZn.783 





Do 







.'.1,4 









Tip shriveled. 



2 Me asurements of segments III, IV, and V combined, 3.355 mm. 



