NO. 2156. SUBFAMILY ALEYRODINAE—QUAINTANCE d BAKER. 403 



abdominal region. It is possible that other pairs are present on the 

 abdominal submargin, but the condition of the specimens is poor. 

 Spines latero-cephalad of vasiform orifice and on the middle of the 

 dorsum, as well as the caudal pair of the case, very long; vasiform 

 orifice (fig, 7) as usual and nearly filled by the operculum; margin 

 composed of evenly rounded teeth, though sometimes irregular, 

 some teeth being longer than others. 



Described from eggs, larvae, and pupae in balsam mounts. 



ALEUROTHREUS (ALEUROTHRIXUS) FLOCCOSUS (Maskell). 



Plate 62, fig. 14. 



Aleurodes floccosa Maskell, Trans. New Zealand Inst., vol. 28, 1896, p. 432. 

 Aleurodes horridus Hempel, Psyche, vol. 8, 1899, p. .394. 



Aleurothrixus floccosus Quaintance and Baker, Journ. Agric. Research, vol. 6, 

 1916, p. 466, fig. 3. 



In 1895 Maskell described this species from lignumvitae, from 

 Jamaica. Three years later Hempel described his horridus from 

 Guava from Brazil, and in 1907 the senior author described the 

 woolly white fly of the orange under the name of howardi. Since 

 these descriptions were made we have had an opportunity to study a 

 large series of specimens from different regions and we have also 

 had available Maskell's type slides of floccosus. There seems little 

 doubt that MaskeU's material and that described by Hempel repre- 

 sent the same species. With liowardi, however, there is one point 

 of difference. Tliis is the comb of hair-like projections on the caudal 

 margin of the vasiform orifice of the pupa case. In collections from 

 orange from different regions both types are found side by side upon 

 the same leaf. Some have the comb and some do not. Tlie relation 

 between these two forms, so closely associated, can be shown only 

 by careful rearing experiments and comparison of all stages. In the 

 meantime, therefore, we use the name /occosifs for those pupa cases 

 lacking the comb, and howardi for those cases possessing it. 



Floccosus was first recorded upon orange by T. D. A. CockereU ^ 

 from Zapotlan, Mexico, collected by C. H. T. Townsend, July 5, 1902. 

 This is also the first record for Mexico. It is, however, in the 

 bureau collection from Laguna, Mexico, on orange, collected by 

 Townsend, April 24, 1896. 



Since complete descriptions of the species have been given by the 

 authors mentioned, nothing further will be added here, excepting the 

 records of the color phases. The typical phase and that represented 

 by the types oi floccosus and by horridus is the yellow one. All of 

 the pupa cases are a uniform yellow. This phase is by far the most 



I Synopsis of the Aleyrodidae of Mexico, in Mem. y. Riv Soc. Cient. "Antonio Alzate," vol. 18, p. 202. 



