PERGANDE NORTH AMERICAN PHYLLOXERINiE. 207 



stem-mothers together with large numbers of eggs and sexual 

 individuals, the cavity being completely crowded. 



Stem-mother. — Length of body 0.4-05"™- and almost as 

 broad. Color, varying shades of orange. Antennse, legs and 

 rostrum faintly dusky, almost colorless. Eyes dark-purple or 

 black and each composed of three simple ocelli. The whole 

 body is densely covered with distinct, minute, conical tubercles. 

 Head about twice as broad as long, almost semi-circular, slightly 

 flattened between the antennae and furnished each side just in 

 front of the eyes with a peculiar, rather prominent, more or less 

 conical, fleshy, colorless and apparently retractile, protuberance. 

 Antennae quite slender, the first joint of almost equal thickness ; 

 the second shorter than the first, thinnest at base, truncate at tip. 

 Joint 3 long and slender and somewhat stoutest beyond the 

 middle, with eighteen or more sharp annulations more or less 

 well defined. lyCgs quite stout, the tibiae distinctly clavate. 

 Anus bluntly rounded and apparently furnished with four hairs 

 around its edge. 



Eggs. — Length o. 1-02"™- Ovoid, polished and pale yellow, 

 the more recently laid, whitish. The smaller produce males. 



Sexual Form, c? ? . — Length of the female 0.4™™-, the male 

 being about one-sixth smaller. Color pale yellow, head, antennse, 

 legs and a rather indistinct band across all segments pale dusky. 

 Eyes dark purple or purplish-red, composed of three large ocelli 

 arranged in a triangle. Surface of whole body covered with very 

 minute conical tubercles and with four dorsal and one lateral row 

 of larger warts on the thorax and abdomen and quite a number on 

 the head, each bearing a slender hair, which, in the female, is 

 simple, but capitate and stouter in the male. A minute conical 

 rudiment of the rostrum in both sexes, not fitted for sucking. 

 A somewhat prominent round tubercle on each side of the pro- 

 and metathorax. The antennse are quite slender ; the first 

 joint stoutest; joint 2 longer than wide. Annulation of third 

 joint rather indistinct and irregular. The thumb-like organ near 

 the tip is quite prominent and has been observed to be distinctly 

 movable. The tips of the thumb and of the joint are furnished 

 with several exceedingly fine hairs, the terminal one, as well as 

 that at the tip of the thumb, in the male, being capitate. Legs 



