194 INTRODUCTION TO ZOOLOGY. 



J— Second basal cell confluent with tlie discal cell, not separated 



by a vein (Dolloliopodidse.; 



JJ— Second basal cell separated from the discal cell by a vein. 

 K— Antenna with a terminal bristle. 

 L— Head comparatively small ; proboscis more or less elon- 

 gated; aluto of the wings usually rudimentaiy. 



(Empidse.* 

 LL,— Head broad as the thorax; Proboscis fleshy; alulEe 



distinct (Platypezidae.) 



KK— Antenna with a terminal style. 



L— First posterior cell open (Emplda3.) 



M— Face convex transversely or with a median ridge, 

 never with a subantennal depression. 

 N— A spurious longitudinal vein, between the third and 

 fourth longitudinal veins, crossing the anterior 



cross vein (Syrphidae.) 



NN— Spurious vein never present (Pipunculidae.) 



MM — Face with subantennal grooves or depressions. 

 N— Proboscis horny and elongate, often folding back 

 near the middle; abdomen never with bristles. 



(Conopidse.) 



NN— Proboscis fleshy and not elongate; if elongate and 



slender, the body with distinct bristles, or the 



bristle of the antenna plumose (MuscidiE.) 



HH— Antenna vrith a dorsal arista. 

 I— Proboscis rudimentary; palpi wanting. Botflies. (Oestridse.) 

 II— Proboscis not rudimentary; palpi present. 

 J — Second basal cell confluent with the discal cell. Small, bril- 

 liant colored, predaceous flies (Dolichopodidse.J 



J J — Second basal cell separated from the discal cell by a small 

 cross vein. 

 K— Basal cell of the wing elongate, anal cell closed toward the 

 margin. 

 L— Face convex transversely or with a median ridge, never 

 w^ith a subantennal groove or depression. 

 M— A spurious longitudinal vein, between the third and 

 fourth longitudinal veins, crossing the anterior 



cross vein (Syrphid^.) 



MM— Spurious vein never present (Pipunculid«.) 



L L — Face with subantennal vertical grooves or depressions. 

 M— Proboscis horny and elongate; abdomen never with 



bristles (Conopidse ) 



MM— Proboscis fleshy and not elongate ; if elongate and 

 slender, the body with distmct bristles, or the 



bristle of the antenna plumose (Musoidse.) 



KK — Posterior basal cell small; anal cell always closed re- 

 mote from the margin (Conopidae or MuscidoB.) 



AA — Parasitic flies. 



B— Parasitic on bats (Nycteribidae.) 



BB — Parasitic on birds or mammals (HippoboscidtB.) 



Note.— The family of Muscidaa includes nearly one-thu-d of all the flies. By 

 some diptcrologlsts it is divided into about twenty-one groups which may be 

 called families. 



Glossary for the Table of Diptera. 



Dorsum— the dorsal or upper side of the body. 



Discal cell — see figure of the wings. 



Aliilw— the backward, membranous extension of the wings. 



Pulvilliie— one of the two pad-like, fleshy cushions between the claws. 



Empodiurrt—the middle appendage of the foot between the claws. Some- 

 times pad-like, sometimes bristle like, sometimes wanting. 



Metatarsus— the first joint of the tarsus; usually larger than the other 

 segments. 



Plumose— twmiaheA with long, soft, feather-like hairs. 



Arista—a, bristle, or strong hair, growing on the antenna. 



