N0.13C2. ALEYRODIDS OF CALIFORNIA-BEMm 509 



cremilations, and from which issues the lateral fringe; near the mesal 

 border of this rim there is found a row of seven or mor(> pairs of 

 short hairs set in conspicuous, tubercled bases; these extend about 

 two-thirds the distance from the cephalic margin toward the caudal 

 end of case. On the dorsum there are hve pairs of conspicuous spines: 

 A pair on the cephalic region, a pair on the meso- and a pair on the 

 meta-thorax, a pair cephalo-laterad of the vasiform orifice, and a pair 

 cau(hid of it; besides these are the usual caudal and latero-caudal pairs 

 of hairs. All sutures distinct, the abdominal ones reaching nearly to 

 the marginal rim and strongly reflexed caudad. Vasiform orifice sub- 

 cordate, broad, and cephalad; operculum relatively the same shape, 

 nearly tilling the oritice and obscuring the lingula, which is spatulate 

 and setose distally. Cephalad of the vasiform oritice are four cres- 

 cent-shaped thickenings in the tergum. The dorsal keel, which is so 

 prominent in the pupa-case, is not well developed at this stage, but the 

 arrow-shaped outline on the cephalic region is distinct; laterad of it 

 are two pores or light spaces. Eye-spots divided, the smaller part 

 anterior. Legs and antennae functional. 



Larva. — Size 0.5 by 0.4 mm.; broadly elliptical; the marginal rim 

 conspicuous, width O.OT mm.; the tubercled hairs seen on the rim of 

 the younger larva have disappeared and their places are occupied by 

 pores; at the caudal end of the rim, there are also two pores and 

 around the rmi is a row of minute ones set close together. The legs 

 and antennae are much reduced in size. 



Pupa. — Size from 1.1-i by 0.83 mm. to 1.6 by 1.3 mm.; broadly 

 elliptical. The case is similar to the larval stages with the following 

 exceptions: The dorsum has a characteristic keel extending from near 

 the cephalic margin to the tubercled vasiform orifice, at the anterior 

 end it is arrow-shaped and from there to the thoraco abdominal suture, 

 sharply ridged, on the abdomen it is conspicuously rounded and broader, 

 and the segments are markedly distinct. On the thorax there are 

 deep, curved depressions which extend caudad to the third abdominal 

 segment; these furrows correspond in position to the leg markings in 

 more transparent and thinner pupa-cases. The dorso-sul)marginal 

 pair of spines are not present, but on t'lie ventral surface, just cephalad 

 of the mouthparts, there are two transverse rows of four hairs eacli; 

 laterad of the donsi-meson on each side there is usually two parallel 

 rows of minute hairs; these are frequently wanting, and in their stead 

 are large pits or pores. The wax tubes of the marginal rim extend 

 about two-thirds its width, the crenulations are distinct, rounded, 

 about as broad as long and with the reentrant angles blunt. Around 

 the margin of case, there is a lateral fringe of white wax rods more 

 or less overlaid with flocculent wax, which varies in length from a 

 narrow, Hat band to a mass as high and as wide as the case; when wide 

 it is usually ragged distally. On the ventral side, the somewhat 

 reduced leo-s are distinctiv se(Mu l)ut the atitenim' ai'c not visible. 



