ALEUROCHITON ACERIS. 87 
Morphological characteristics — Female. — Length 1.79 mm. Head 
without median suture; viewed from the side, one and one-half times 
as long as wide. Compound eyes long and reniform, not divided. 
Ocellus large and distinct, very nearly touching the upper margin of 
the compound eye. 
The antennae are shorter than the combined length of head and 
thorax. The second joint is broadly pyriform in shape; it exceeds 
in length the half of the third joint. The length of the third joint is 
0.241 mm., longer than all the succeeding joints combined. Joint IV 
0.048 mm.; joint V 0.75 mm.; joint VI 0.058 mm.; joint VII 0.051 
mm. in length. Joints III-VII are all provided with fine crosswise 
wrinkles and with short hairs. The seventh joint is provided at its 
terminus with fine bristles that are rather long. Joints III, V-VII 
have small sensory organs. 
Kostrum three- jointed. The third joint twice as long and a little 
more contracted than the second. All the joints provided with fine 
hairs and with short scattered bristles. 
Scutellum triangular, provided with a longitudinal suture. 
The legs are rather long. Tibia : Joint I 0.46 mm. ; II 0.53 mm. ; 
III 0.75 mm. in length. Metatarsus: Joint I 0.189 mm.; II 0.172 
mm.; Ill 0.214 mm. in length. The joints provided with very fine 
hairs and with spines that are more or less distinctly arranged in 
rows. Third joint of the tibia more or less like that in Aleurodes 
proletella, fragaria, etc.; it has two claws, short and of the same 
length as the apical bristles of tlie tarsus. The paronychium is large, 
extended in spatulate or foliate shape, almost tavice as long as the 
claws. 
Wing bordered as in Al. proletella. Length 2.2 mm. Width 1.1 
mm. The middle vein forked behind the middle. The main branch 
reaches the wing border. The submedian vein is long and delicate. 
The middle vein of the hind wing is unbranched. 
Abdomen large, oval. The four ventral plates more finely reticu- 
lated than in Aleurodes proletella. The operculum of the anal aper- 
ture is as long as it is wide ; its posterior margin sinuate. The lingula 
as long as the operculum. The genital appendages sharply pointed. 
Male. — The anal aperture is smaller, the operculum is longer, 
more contracted, and more strongly sinuate. The penis is only 
slightly bent upward. The genital appendages are not so decidedly 
curved; their terminus is pointed with shape of a claw, and below 
the end there is a small sharp tooth. The terminus is provided with 
a few long bristles. 
The puparium is arched, oval, slightly sinuate at the posterior 
margin, and also sinuate across the anterior margin. The dorsal 
side is almost completely covered with a white waxy crust. ' Only 
