ASHMEAD : CLASSIFICATION OF THE CHALCIU FLIES 345 



TABLE OF TEIBES. 

 Tarsi 5-joiiited .Tribe I. Apbeliniiii. 



Tarsi 4-jointed Tribe II. Pteroptriciui. 



Tribe I. Aijlielinini . 

 The yi(;e-jointed tarsi distinguish the tribe. The majority of the species con- 

 fine their attacks to various genera of scale-insects, or bark-lice, belonging to the 

 famil}'' Coccidse. A few, however, in the genus Aphelinus, while usually bred from 

 Coccidas, also attack plant-lice belonging to the ftimily Aphididse. All the species, 

 except probably the latter, which may be hyperparasitic on some Encyrtinse, are sup- 

 posed to be primary parasites, and are of the greatest importance in destroying the 



destructive bark-lice {Coccidce). 



TABLE OF GENERA. 



1. Females 2 



Males 19 



2. Wingless forms 18 



Winged. 



Front wings with a hairless oblique line extending from tbe marginal vein towards the base of 

 the wing ; antennae 5- or 6-jointed 12 



Front wings without such a line. 



Antennae 8-jointed 3 



Antennae 3-jointed 11 



3. Club of antennae 3-jointed 4 



Club of antennae 1- or 2-jointed 8 



4. Wings with a short marginal fringe 5 



Wings with a long marginal fringe 7 



5. Stigmal vein short but distinct, always present. 



Marginal vein as long as, or longer than, the subcostal vein 6 



Marginal vein much shorter than the subcostal vein. 



Prospalta Howard (type P. murlfeJdti How.). 



6. Flagellum strongly compressed, the first joint of the fimicle about twice as long as the pedicel, the 



following shortening ; hind tibite flat, with short stiff bristles behind. 



Aneristus Howard (type'^. ceroplastw How.). 

 Flagellum not compressed, subcylindrical, the first joint of funicle not tAvice as long as the pedicel . 

 hind tibiae normal, without short, stiff bristles behind. 



Coccophagus Westwood (type C. pulcliellus Westw.). 



7. Stigmal vein absent Aspidiotiphagus Howard (type Coccophagus citrinus Craw.). 



8. Club of antennae 2-jointed 9 



Club of antennae 1-jointed 10 



9. Abdomen, seen from above, short, oval, depressed, beneath boat-shaped or carinate ; hind tibiae nor- 



mal Encarsia Forster (tj'pe E. tricolor Forst.). 



Abdomen, seen from above, subovate, flat, beneath subconvex ; hind tibiae behind armed with stiff 



bristles Myiocnema Ashmead (type M. comperei Ashm.). 



10. Abdomen short, depressed, not boat-shaped beneath, ending in a prominent ovipositor. 



Ablerus Howard (type Centrobia clisiocampse Ashm.). 



