312 THE CANADIAN RNTOMOLOGIST. 



and winged viviparous females. None of these, however, could be 

 specifically determined by Dr. Riley and his assistants. November 23 

 there were still many of the egg-laying females and males to be found, 

 and a great number of eggs scattered about over the plants. The 

 oviparous female is very robust, body green ; eyes brown and coarsely 

 granulated ; antennge, except first two joints (the bases only of which are 

 black), tip of beak, feet, tips of honey tubes, black ; tips of femora and 

 tibiae, dusky; honey tubes reaching half the length of tail, slender. 



The males were light-bodied, with the wing much longer proportion- 

 ally than in the winged females ; black, with margins of abdomen greenish ; 

 wing veins dusky ; bases of wings very light yellowish ; antennse very 

 dark brown at base, the remaining portion nearly black ; eyes brown ; 

 anterior femora very light at base and darker toward extremity ; middle 

 and posterior femora with less light colour at bases ; tibiae very dark 

 brown, nearly black ; tarsi black ; honey tubes long, slender, piceous, 

 darker at base. 



The eggs were at first of a glassy green colour, but turned to black after 

 being deposited a short time ; a little more than twice as long as broad, 

 and appeared to be slightly stuck to the leaves of the plants. 



During the following March these eggs gradually disappeared, and the 

 plants again became populated with Siphonophora,.hw\. specimens sent to 

 Washington were not determinable, except as to genera, and all were 

 wingless viviparous females. 



Strongly suspecting that I was dealing with the same species as had 

 been brought into the cage on the Squash, there having been no way by 

 which this could have escaped or another species entered, early in April 

 I planted a number of Squash seeds in the cage. As soon as the young 

 plants appeared they were at once attacked by apterous viviparous females, 

 and on April i8th I secured winged females. On forwarding these to 

 Washington, my own determination of the species as .S". cucitrbitce was 

 promptly verified. In this case, the environment was, of course, unnat- 

 ural, and the insects were obliged to use these two species of plants in 

 passing through their cycle, and hence they might find more congenial 

 host plants in the fields ; but it seems to me that it would be safe to 

 assume that the melon-louse can readily pass from its summer food plant 

 to either one or both of these, and from them give origin to winged 

 viviparous feniales in the spring, to return to the original host plant, 



