THE CANADIAN ENTOMOLOGIST. ,"3 



Apterous Viviparous Female. 



Length, 1.85 (r. 50-2. 10) mm.; width, 1.05 (0.90-1. 10) mm.; 

 antennae, 1.80 (1.75-2.20) mm., III., 0.48 (0.40-0.64) mm., IV., 0.37 

 (0.35-0.41) mm., V., 0.25 (0.20-0.32) mm., VI., o. 13 (0.10-0.15) mm., 

 VII., 0.45 (0.38-0.54) mm.; Tibia, I., 0.81 (0.70-1.00) mm., IE., 0.83 

 (0.70-1.00) mm., III., 1. 15 (0.93-1.40) mm.; Cauda, 0.20 (0.16-0.22) 

 mm.; Cornicles 0.50 (0.48-0.60) mm.; Rostrum extending to mesocoxse. 

 Eyes, tips of cornicles, and tarsi black, otherwise pure whitish, with 

 indistinct greenish mesal stripe on abdomen, sometimes with a few 

 capitate hairs on caudal segments, tibia, and head ; no lateral tubercles ; 

 antennae lie flat over back when at rest, and the gibbous tubercles are 

 thus bent upwards. Thirteen specimens. 



This species is closely allied to M. achyratites, Monell ( M. malvce, 

 Oest.), as described by Monell and Oestlund. The apterous females are 

 distinguished from it by the longer antennae, which are whitish, eyes 

 black instead of red-brown, and abdomen whitish instead of pea-green 

 as in malvce. The winged female is distinguished by having the inner 

 angles of I. straight or but slightly rounded, VII. slightly longer than 

 III., and cornicles black. The apterous females are very similar to 

 Siphonophora calendulella, Monell, but the description of that species is 

 too brief to be recognizable. Monell mentions that a species closely 

 allied to S. achyratites occurs on lettuce. 



The winged females bear a resemblance to Rhopalosiphum diauthi, 

 Schr., but are smaller, the cornicles are not swollen and are black, and 

 only III. bears sensoria, while Oestlund describes the winged dianthi as 

 having sensoria on III., IV. and V. 



Specimens of this species were kindly loaned me by Prof. W. G 

 Johnson, from Baltimore Co., Md., collected on lettuce, February, 1899; 

 were found by me on garden peas, November 1, 1900, at Newark, Del., 

 and were collected by Prof. G. H. Powell, May 3, 1897, on eggplant 

 under glass — to which they were doing considerable injury — at the same 

 place. 



The description given by Thomas under Siphonophora lactucce, 

 Kalt., refers either to this species or M. achyratites, Monell. 



Types deposited in the U. S. Nat. Museum. Type No. 5422. 



Explanation of Plates. 

 Plate II. (page 34). 



1. "Siphonophora pisi" from G. B. Buckton. 



