1900] ENTOMOLOGICAL NEWS. 3QI 



small number of individuals in all stages of development 

 from the small larva to the full-grown, viviprous, apterous 

 female. During the months of April or May these colonies 

 begin to grow rapidly, and by mid-Summer the whole root of 

 the infested plant is often quite covered with the .-Ip/iis and the 

 cottony secretion. Some time during the Summer just how 

 early has not yet been determined winged forms begin to 

 appear ; these increase in number until as late as November 

 1 5th, when the winged individuals in the colony frequently out- 

 number the wingless forms. These winged forms are also 

 agamic, viviprous females, no males having as yet been dis- 

 covered. After leaving the plant, they sometimes fly for con- 

 siderable distances before settling at the root of another plant, 

 where a new colony, the Winter colony, is established. The 

 beets may become infested either by one of these winged 

 females establishing a colony on them, or, as is probably more 

 often the case, by forms which are already in the soil attacking 

 the small rootlets as soon as they are sufficiently developed. 



The wing venation and the structure of the antennae place 

 this species in the genus Pemphigus, among the root-inhabiting 

 forms ; but, so far as I can learn, it has never been described. 

 So a brief description is given : 



Pemphigus betae n. sp. Wir.ged, viviparous females: length 2 mm.; 

 alar expanse 6.75 mm.; head, thorax and appendages bluish black, pru- 

 inose. Abdomen, after the hoary secretion is removed, dark-green with 

 considerable flocculent m.itter on the posterior segments. Antenna: 

 i mm. long, annulations indistinct ; joints all somewhat constricted at 

 base ; third joint longest, last joint next in length and more slender than 

 the rest ; unguis distinct. Third and fourth joint with transverse senso- 

 ria. Eyes large, very dark brown. Wings somewhat smoky ; stigma, 

 all the veins and the narrow space between the costal and subcostal veins, 

 brown ; first and second discoidals arising close together, more rarely a 

 very short distance apart; basal third of cubital obsolete. Apterous 

 individuals yellowish, sometimes so covered with the whitish secretion as 

 to make them appear almost white ; legs, antenna,-, distal half of back, 

 and a rather large spot on the dorsal aspect of the head very dark brown ; 

 eyes very small, almost black ; tne white tl jcculent secretion is confined 

 to the last three or four segments of the abdomen, and is often i mm. 

 long, sometimes even longer. 



Larva; like the apterous individuals, only more slender, and in the 

 earlier stages with only five joints to the antenna;, the last of which is the 

 longest. 



