I FIFTH REPORT OP THE ENTOMOLOGICAL COMMISSION. 
On the under side of the leaf it is much larger than in any of the 
other Leaf-galls, conical, cither slightly narrowing apicallyor, more fre- 
quently, Slightly enlarged. The sides are vertical or nearly so; the 
top broadly rounded without median depression or central nipple. 
Size very variable; averaging in height to 7""", and in diameter at 
ba^e 1 to o" 1 " 1 . Color pale greenish yellow, with the tip more brownish ; 
surface opaque, rngosely reticulate; at base often covered with a 
whitish prninesoence, rarely with a few scattered hairs near the top. 
(Fig. 202, a.) 
Fig. 202.— Gall of Pachypsylla c. -mamma: a, leaf with 
galls from underside — natural size ; b, seetiou of gall 
showing cupdike depression, and insect in cavity : r. 
pupa- enlarged. (After Riley.) 
The walls of the gall are hard and woody, at the bottom averaging 
1.75 mm , at the roof 0.75 maj in thickness. The cell (Fig. 202. b) is large, and 
in cross- section much more 
crescent-shaped than in the 
preceding species. The ma- 
ture pnpa issues through an 
oval slit sawed through the 
roof, always near the side 
where the wall is less thick. 
42. P. celtidis-pubescens u. 
sp. — This gall on the upper 
side of the leaf is represented 
by a small circular cup-shaped 
impression, surrounded by a rather wide, thickened, and elevated 
margin, and furnished at the bottom with a small, usually star- 
shaped, median nipple. The bottom and sides of the impression are 
-T 
Fig. 203. — Paclu/jivylla c. -mamma: adult— enlarged. 
(Original.) 
