No.lse^ ALEYRODIDS OF CALIFORNIA— SEMIS. 477 



close observation on the part of the author has failed to reveal them 

 feeding; Prof. A. L. Quiiintanco, however, in a letter, writes that he 

 has frequentl}' observed adults of ^1. ahutllo)icii.s llaldenian feeding. 

 Experiments for determining the average duration of adult life were 

 not satisfactory, as the .specimens had to be confined in an artificial 

 environment that would not give results identical with natural condi- 

 tions. From data gathered, it is probable that there are at least two 

 broods each 3'ear, the adults in this \icinity emerging fi'om the pupa- 

 cases and laying in April and May, and again in September, October, 

 and November of the same year. 



Family ALEYRODIDiE. 



Small to minute insects infesting plants; oviparous; metamorphosis 

 incomplete (?); immature stages quiescent, attached by sucking mouth 

 parts to the leaves; adults free and active, covered with granules of 

 white wax. 



Adults of both sexes with four wings, which are held horizontally 

 and extend beyond the abdomen when the insect is at rest. Wings 

 rounded, pure white or w^itli dusky spots, margins golden-yellow and 

 serrulate or "beaded'' all around, each serrulation with three to five 

 minute, delicate hairs; color and serrulations of the costal margin 

 more pronounced; fore wings with a single, median vein; costal mar- 

 gin bearing nine spines at base. Color of bod}^ 3^ellow; head and 

 thorax usualh' darker; the entire body occasional!}' with conspicuous 

 brown markings. Head small, convex above, rounded anteriorly. 

 Eyes two; red, brown, or l)lack; either more or less constricted near 

 the middle, reniforni, or divided into two lobes, the lesser of which is 

 anterior, In-ighter in color, and W' ith smaller facets. Anterior to each 

 eye is a single small ocellus. When mounted the divided eyes appear 

 single, and only a careful inspection under a high power of micro- 

 scope will show the diti'erence in structure. Antenme of seven seg- 

 ments, the first of which is shortest and the third longest; the first 

 two segments are simple and stout; segment one. cup-shaped; segment 

 two, subpyriform; segments three to seven, inclusive, cylindrical and 

 closely ringed with minute hairs. Legs long and slender, feet with 

 dimerous tsirsi, terminating in three claws, of which the middle one is 

 smaller than the other two, and bears a number of spines. Rostrum 

 projecting from the under side of head, composed of a single segment, 

 at th(» apex of which are the seta^ that form the suctorial tul)e; from 

 the l)as(^ arises the long, 8-segmented mcntum, sul)cylindrical in shape, 

 free for its entire length, and inclosing the rostral setie. Thorax with 

 about e<iual distinct segments. Abdomen roundly tapering, tei'mi- 

 nating in the genitalia; the first segment constitutes a very slender 

 peduncle; on the dorsal surface of the last segment is the vasiform 

 orifice (tig. 41, Plate XXXIII). In {\\v adults this characteristic organ 

 is but little differentiated in general appc^arance and of no specific tax- 



