t>ERGANt)E — NORTH AMERICAN PHYLLOXERInA. 25.9 



I append herewith a more detailed description of the different 

 forms observed. 



Apterous female. — Length about i""-. Color pale yellow. 

 Eyes red. Antennae and legs finely dusky. Body elongated, 

 having four short and stout capital tubercles, two of them frontal 

 and the other two just behind them ; . surface indistinctly rugose 

 and densely granulated. Antennse with the third joint slender, 

 narrowest at base, divided ,by about 15-18 rather shallow and 

 somewhat scaly annulations ; its tip truncate and provided with 

 apparently two fine hairs ; thumb minute, though distinct. 



Egg. — Length about 0.2™"-. Color white or faintly greenish, 

 transparent and polished. Shell very delicate but faintly pitted. 

 Shape ovoid, slightly flattened and securely glued on the flat side 

 to the leaf. 



Pupa (with long tubercles) . — Length of body of the largest 

 observed about cy"""-. Color pale yellow or pale orange. Sur- 

 face of body quite coarsely rugose. Antennse and legs faintly 

 dusky. Eyes red, scarcely indicated above, more distinct beneath; 

 their place above mostly occupied by a large, much elongated, 

 somewhat tapering tubercle. Four similar tubercles of same 

 size fringe the front margin of the head, and two still more slen- 

 der tubercles rise from the middle of the head. The prothorax 

 is furnished across its anterior and posterior margins with a row 

 of four shorter and on its lateral margins with two longer 

 tubercles. There is a transverse row of four similar tubercles on 

 the meso- and meta thorax; two longer, lateral ones on the meso* 

 and one each side on the metathorax. The abdomen is fur- 

 nished, medio-dorsally, with two rows of six smaller tubercles, 

 which gradually become longer towards the end of the body,, 

 while each segment, except the last, bears a single lateral 

 tubercle, growing gradually shorter toward the end of the body. 

 The last segment is surrounded by four small, rounded tubercles, 

 each bearing at tip a short spine. All tubercles appear to be 

 slightly annulated. Antennae long and rather stout, without 

 annulation, with a fine, slightly capitate hair at tip, and another 

 a. little below it ; thumb small, though quite distinct. 



Pupa (with short tubercles). — This is the most common form. 

 It is of about the same size, or slightly larger than the other, and 



