70 



MISCELLANEOUS RESULTS OF WORK OF BUEEAU — IX. 



most dense on the middle of the segments. Denuded of secretions, the pupa case 

 is seen to be at first almost flat, but later becoming rather convex as the insect 

 develops, with segments distinct. 



Dorsum with pair (1) of strong setse on first abdominal segment, a pair (2) at vasi- 

 f©rm orifice, and a pair (3) at, but not on, caudal margin extending some distance 

 beyond margin of case. There is also a pair of minute marginal spines (a) at the 

 anterior end, and another (b) at the posterior end of body. The relative lengths of 

 these spines are as follows: 



Pair 1 2 3 a b 



Relative lengths ,... 14 16 10 1.5 2.5 



There is also a pair of small bristles on the venter beneath the vasiform orifice. 

 Vasiform orifice relatively small, subcordate, the rim dark brown, from 6 to 8 strong 



setse or spines arising from caudal 

 margin; operculum largely filling ori- 

 fice, the distal margin with two faint 

 notches; lingula not distinguishable. 

 (See fig. 22.) 



The adult. — Usual, lemon - yellow, 

 after emergence becoming coated with 

 white waxen secretions; wings pure 

 white, without darker markings, held 

 along sides of abdomen, but not 

 meeting over the dorsum. A con- 

 siderable amount of flocculent white 

 wax is secreted, but not as copious 

 a supply as is secreted by the adult 

 of P. ■persese. In female: Length of 

 body, 0.42 to 0.47 mm.; length of fore 

 wing, 1.1 mm.; width of fore wing, 

 0.36 mm.; length of antenna, 0.31 

 mm.; length of hind tibia, 0.035 



Fig. 22. — The woolly white-fly: Pupa case and details. 

 Greatly enlarged. (From Quaintanee.) 



mm.; relative lengths of antennal segments as follows: 



Segment 1 



Relative lengths 1.5 



3 4 5 6 7 Spine. 

 10 1.3 2.5 2.6 1.5 0.7 



FOOD PLANTS. 



The woolly white-fly infests the various species of citrus, the 

 guava, and the mango. While found on the mango at Tampa by 

 the writer, its presence on this plant is probably the result of acci- 

 dent. Mr. W. L. Tower is authority for its occurrence on guava in 



Porto Rico. 



DISTRIBUTION. 



This species occurs on several islands of the West Indies, but 

 more especially in Cuba. It is now established at Tampa, Fla. 



NATURAL ENEMIES. 



While no predaceous insects are known to attack this aleyrodid. 

 Cook and Horn*^ have reported it parasitized by the ''red fungus," 



a Cook, M. T., and Home, W. T., Cuban Exp. Sta. Bui. 9, p. 31, 1908. 



