470 Journal of Agricultural Research voi. vi, no. la 



and Florida. While not as important as D. ciiri, it is nevertheless 

 decidedly noxious. It is also known to occur in Cuba and Mexico. No 

 specimens of this insect were found in the Woglum collection of white 

 flies from India, Ceylon, and other points in the East visited by him. 

 By reason of its affinities, D. citrifolii is, however, almost surely oriental 

 in origin. 



This species, with one exception, is known to attack only Citrus plants. 

 It was found on Ficus nitida growing in greenhouses at Audubon Park, 

 New Orleans, La. 



Paraleyrodes perseae (Quaintance) 



AleuTodes perseae Quain., 1900, U. S. Dept. Agr. Div. Eat. [Bui] 8, Tech. Ser., p. 32. 



Paraleyrodes perseae Quain. and Baker, 1913. U. S. Dept. Agr. Bur. Ent. [Bui.] 27, pt. 1, Tech. Ser., p. 82, 



This species is known only from Florida, where it is frequently found 

 on orange, though never in destructive numbers thus far. It also feeds 

 upon Persea, the avocado (Persea americana) , and doubtfully on per- 

 simmon (Diospyros spp.) . Several species of the genus are common in the 

 West Indies, perseae being the only one known from the United States. 



Trialeurodes floridensis (Quaintance) 



Aleurodes floridensis Quain., 1900, U. S. Dept. Agr. Bur. Ent. [Bui.) 8, Tech. Ser., p. 26. 



T. floridensis has thus far been recorded by the Bureau of Entomology 

 only from Florida, where it is rather generally distributed. It infests 

 avocado, guava, Annona squamosa, and the orange. While often 

 very numerous on guava and avocado, it is at present of no importance 

 on orange. 



Trialeurodes vitrinellus (Cockerell) 



Aleyrodes vitrinellus Ckll., 1903, in Ent. News, v. 14, no. 7, p. 241. 



The type of this species is from Mexico on orange. Apparently the 

 same insect has been taken in southern California on oak. Its injuries 

 to orange in Mexico are probably not great. 



Tetraleurodes mori (Quaintance) 

 Aleurodes mori Quain., 1899, in Canad. Ent., v. 31, no. 1, p. i. 



This indigenous species (PI. LXIX, fig. 2) is widely distributed over 

 the eastern United States and occurs on a large variety of plants, as 

 mulberry, sycamore, maple, dogwood, hackberry, persimmon, holly, 

 mountain laurel, etc. It has been found several times on orange, but 

 not as yet in injurious numbers. That it may become troublesome under 

 certain conditions, however, will be evident from the discussion relative 

 to T. mori, var. arizonensis, which follows: 



