354 NEW YORK STATE MUSEUM 



Mandible with a pair of apical bristles, palpus of the maxilla 

 with setae (8) 



8 Middle tooth of the labium enlarged, ventral surface of 



labium with five pairs of setae [pl.37, flg.6] venustum 



Middle tooth not enlarged (varieties of venustum) (9) 



9 Labium with four pairs of ventral setae [pl.37, flg.l4] var. a 



With seven pairs of setae fflg-S] var. p i s c i e i d i u m 



Pupae 

 (Arranged according to the number of filaments in each respiratory 

 tuft) 



1 With six filaments 



a Legs in their cases appear bicolored" venustum 



& Legs unicolored m e r i d i o n a 1 e 



2 With eight filaments 



ft Pupa 4.5mm long; Arizona sjiecies. Pupa described in 

 Am. Ent. Soc. Trans, p.45. 1893. 



6 Less than 4mm long; eastern species 



venustum, var. piscicidium 



3 With nine filaments. Pupal case like that on pl.35, fig.5. . .p i c ti p e s 



4 With 10 filaments var. a of venustum 



5 With 12 filaments. Pupal case [pl.35, flg.5]. From Santa 



Cruz mountains, CaJ. [p.387] 



6 With 16 filaments vittatum 



7 With 24 to 48 filaments [pl.33, fig.lO] pecuarum 



8 With 60 or more filaments h i r t i p e s 



Imaffines 



1 Ground color of the thorax and abdomen deep yellow (2) 



Gi-ay or black; its hairs may be pale (3) 



2 " Femora with black tip, length of fly 2mm." Mexico, .ochraceum 

 " Femora without black tips. Length 3 to 4.5mm. Rocky 



mountains " f u 1 v u m 



3 Hind tarsi with its basal joint partly yellow; legs bicolored (9) 



Hind tarsi unicoloreds (4) 



4 Halteres dusky; thorax not striped (5) 



Halteres white or yellow; the female with striped thorax and 



bifid tarsal claws (6) 



5 Body black; the female with dense yellow pile, her tarsal 



claws simple; the mate with dense hair on the legs, his 

 tarsal claws trifld. The wing with its radius three 



branched. Length 3 to 4.5mm .h i r t i p e s 



"Body gray, legs reddish gray, feet black; length 3mm." 

 This is said by Mr Ooquillett tO' be the samie as pecua- 

 rum Riley i invenustum 



6 Males, eyes contiguous (7) 



Females, eyes separated by a distinct line .(8) 



'In order to see this it will be necessary to examine nearly mature speci- 

 mens and perhaps to draw them from their pupal skins. 



2 The male of pictipes sometimes has legs nearly unicolored; it is 

 however included in the preceding section. 



