30 CLASSIFICATION OF THE ALEYRODID^. 



In the median dorsal area, all around, there are a large number of 

 mouths of wax-producing glands, collected in six distinct groups, of 

 which three are arranged at the right and three at the left of the 

 longitudinal diameter of the body of the insect. The middle group 

 on the right, as well as that on the left, is quite distinct from the 

 contiguous groups, of which the two anterior ones, as well as the two 

 posterior ones, unite respectively at the anterior apex and at the 

 posterior apex of the body of the insect, at wdiich points these groups 

 are of their smallest width. The wax secreted by these wax-pro- 

 ducing glands is that which goes to form the above-recorded six 

 waxy tentacles. Other glands of similar nature, symmetrically dis- 

 posed, are found spread out upon the tegument comprised between 

 the groups of which we have just spoken, but such glands are w^ant- 

 ing, with the exception of the row of circummarginal glands already 

 described, on the part of the tegument outside of the j^rincipal groups. 



The anal aperture, as compared with that of the preceding species, 

 is much smaller in size, and the operculum which covers it is, in com- 

 parison, much wider than long, the length being scarcely more than 

 one-half of the width. The lingula, by its shape and by the number 

 and disposition of the sightly hairs with which it is ornamented, 

 resembles that of the preceding species except that the dimensions 

 are proportionate to those of the respective operculum. 



As regards the venter the insect presents no special features except 

 the legs which, like those of Aleurodicus lahillei, carry at their apex 

 a robust claw rather than a pulvillus. 



Length of body 1.500 mm.; width of body 1.120 mm.; length of 

 the waxy tentacles about 5 mm. ; width of the waxy tentacles about 

 0.5 mm. 



Advlts. — Not known. 



Habitat. — Collected at Jalapa, in Mexico, upon the leaves of a plant 

 the species of which is undetermined. 



The insects, for the most part collected in numerous colonies, are 

 ordinarily attached to the sides of the middle vein of the leaf, dis- 

 posed alternately on the one and the other side of this vein, forming 

 in their totality an elegant design which shines upon the verdure of 

 the leaf, thanks to the perfect whiteness of the waxy tentacles which 

 arise from the back of the insect. 



Dialeurodicus tessellatus n. sp. 



(PI. VI, fig. 1; PI. VII, fig. 2.) 



From Ceara, Brazil, on Eugenia mitchelli. Received January, 

 1900, from Mr. F. Richa. This species in the pupal stage closely re- 

 sembles I), cochercllii, but differs in the character of margin of case, 

 in the vasiform orifice, absence of w-ax pores on dorsum, and darker 

 color of eggs and pupa case. 



