THE CANADIAN ENTOMOLOGIST. 221 



C : 



resemble young wingless plant-lice and are of a dark yelluw color. They 

 change their skins and color repeatedly and acquire wing-scales or rudi- 

 mentary wings, then fix themselves to the bark in rows and remain sucking 

 the sap until about to undergo their last change, when they disperse 

 among the leaves and appear in their winged form." 



This account has been copied by nearly every economic Entomologist 

 who has had occasion to treat of these little pests. Even Dr. Harris, in 

 his well known Treatise, nor a later writer, Prof. Thomas, give no new 

 facts. 



From my studies of some undescribed species in Florida, and other 

 known facts respecting this family, I feel justified in stating that Kollar's 

 account cannot possibly be correct j especially is this true with regard to 

 its coming forth from its winter retreat provided with wings and in his 

 description of the egg. It does not agree with my observations, nor with 

 those ofT.eon Defour. To this celebrated Frenchman and indefatigable 

 biologist are we indebted for the first accurate description of a Psylla's 

 egg. Those interested will find an account in his " Recherches anato- 

 miques et physiologiques sur Les Hemipteres," p. 358, and on plate xvii., 

 fig. 191 b. c, good figures of the egg. A translated account may also be 

 found in " Thomas' 8th Illinois Report," p. 16. 



In the summer of 1879 I noticed for the first time that the leaves of 

 the young Persimmon trees ( Diospyros virginiatia) in the vicinity of 

 Jacksonville were very much discolored, curled and distorted; on most 

 of them, too, were numerous small warty-like galls. A thorough examin- 

 ation under the curled and twisted parts of the leaves revealed numerous 

 small, flattened, hemipterous bugs, arranged in rows, and covered with a 

 fine mealy or powdery substance ; on disturbing they secrete large watery 

 globules, the color of milky water. 



A careful study of these during the past two years has enabled me to 

 completely work up their life history, as well as the partial histories of 

 other species which I shall now proceed to give, after giving a list of the 

 known N. A. species. 



Genus Diraphia, Waga. 



1. D. vernalis. Fitch. 3. D. calamorum, Fitch. 



2. D. femoralis, Fitch, 4. D. maculipennis, Fitch. 



