THE CANADIAN ENTOMOLOGIST. 165 



ON TWO INTERESTING NEW GENERA OF SCALE INSECT 



PARASITES. 



BY L. O. HOWARD, WASHINGTON, D. C. 



Nearly all the Chalcidid parasites of Coccid^e belong to the sub- 

 families x\phelinin?e and Encyrtinse. So universal is this rule that it is 

 remarkable to rear anything else from a Coccid (excluding, of course, 

 hyperparasites)*. One or two Mymarids and the species of the curious 

 subfamily Signiphorinse live in the eggs of scale insects, and we are just 

 beginning to realize that there is a peculiar group of genera allied to the 

 old subfamily Pirenin^e which also have this habit. 



The first of these insects to be recognized as a primary scale insect 

 parasite was a species of the genus Tomocera described by the writer in 

 1880 and reared from Lecanium olece from California. This name in 

 1885 was changed to Dilophogaster on account of the occurrence in 

 Thysanura of a genus Tomocerus. In the meantime, however, Cameron had 

 erected for the same form, from specimens received from the Hawaiian 

 Islands, his genus Moraiiilla. According to the present rules of classi- 

 fication, however, Tomocera may stand in spite of its identical etymo- 

 logical signifiance with Tomocerus. 



Another of these genera was described by Dr. Riley in 1890 as 

 Ophelosia from specimens reared from Icerya purchasi in Queensland. 

 A third — Walker's genus Euiiotus — has recently been found by Mr. W. 

 G. Johnson to be parasitic upon Lecanium scales in Illinois, as pointed 

 out by the writer in Technical Bulletin No. i, Division of Entomology, 

 U. S. Department of Agriculture, and a fourth — Scutellista, Mots. — has 

 been found by Dr. Berlese to parasitize Ceroplastes scales in Italy. 

 This form has been redescribed with synonymical notes by the writer in 

 the " Revista di Patologia Vegetale." 



Aside from the matter of tibial armature, these genera seem closely 

 allied and to possess on the whole strong mutual affinities. The shape of 

 the head, its acute occipital margin, the mesonotal characters, the lo-jointed 

 ( $ ) and 9-jointed ( $ ) antennae, the gready enlarged second segment of 

 the abdomen, together with other characters point to a subfamily not yet 

 recognized in our classification of the ChaJcididae, and the uniform 

 Coccid-feeding habit binds the group still more closely together. 



* Representatives of Pachyneuron, Euneura, and Hypsicamara have been reared 

 from Coccifla;, but those of Pachyneuron are ahnost certainly hyperparasites, and the 

 others may be ; while the species of Tctrastiihus quite commonly so reared are un- 

 doubtedly secondary. 



