11 
of the eyes. Soon after mounting, the relative lengths of the joints of 
the antennz of adults are much more readily distinguished than later. 
The other series should consist of adults preserved dry in vials, and 
the infested leaves so pinned that the waxy secretion from the larye 
and pupa-cases will not be in any way damaged. . 
Tam under obligations to Prof. 'T. D. A. Cockerell for bibliographic 
references, numerous specimens sent, and other courtesies; and I have 
been much aided by the careful entry notes made by Mr. Theodor Per- 
gande on the material received by the Division of Entomology and 
kindly furnished me by Dr. L. O. Howard. 
Family ALEURODIDA. 
Small to minute insects infesting the leaves of plants, usually on 
the lower side; the immature stages scale-like; the adults with two 
pairs of wings, and covered or dusted with a whitish meal-like secre- 
tion of wax. 
In the immature stages the body may be more or less covered by a 
secretion of wax, frequently quite copious. The most distinctive 
Aleurodid character in the larval or pupal stages is in the presence of 
a subovate, triangular or semicircular opening on the dorsum of the 
last abdominal segment, known as the ‘‘ vasiform orifice.” This con- 
sists of the orifice; the operculum, a more or less lid-like structure 
attached to the rim of orifice cephalad, and the lingula, a more or less 
slender tongue or strap-shaped organ, attached cephalad within the 
orifice and extending frequently quite beyond its caudal margin. 
In the adults the mentum is three segmented, inclosing the three 
rostral sete; antennz seven jointed, the first two joints short and 
thick, the others slender and numerously ringed. Eyes usually some- 
what constricted near the middle, dumb-bell shape or reniform, or 
even completely divided. Above each eye is a single ocellus.  Tarsi 
two jointed, with three terminal claws, the middle one of which is 
short and small. The wings when at rest are nearly horizontal, extend- 
ing caudad considerably beyond the abdomen, rounded distally. Both 
fore and hind wings may be immaculate or variously spotted or banded, 
usually with dusky or reddish.’ 
Genus ALHURODES Latreille. 
With the characters of the family. Adults, with but a single basal 
branch to vein of fore wings; hind wings, with but a single vein. 
1For a more detailed account of the characters of Aleurodidze, see Maskell, Trans. 
N. Z. Inst., 1895, p. 415. 
