34 



50. Sides ol'facodcstituto of stout niiicrochjuta- 60. 



Sales of face hearing one or more pairs of stout, downwardly curving macrocbtetie 

 lielow the lowest froutal bristles, arista thickeued on tbe basal tbree-fourtbs. 



(p. 77) I'araplaijla. 



60. Arista tbiekcned almost to the tip, tbird vein bristly nearly to tbe small eross- 



veiu (p. 77) Mctaplnijiu. 



Arista never tbickened to tbe middle, tbird vein bristly less tban balfwuy to t^io 

 small erossvein (p. 76) Hcteroplenna. 



61. Faeial ridges bristly on less tban tbe lowest fimrtb 63. 



Facial ridges bristly ou at least tbe lower balf 62. 



62. Penultimate Joint of arista over twice as long as broad, bend of fourtb vein 



destitute of a distinct appendage (p. 137) Clurtogadia. 



Penultimate joint of arista sborter tban broad, bend of fourtb vein witb a dis- 

 tinct appendage (]». 127) Araba. 



63. Antenna' reacbing only sligbtly below middle of face 6-1. 



Antenna^ reacbing to or below tbe lowest fourtb of tbe face 72. 



61. First posterior cell o])en 65. 



First posterior cell closed, tbe petiole as long as tbe small erossvein, cbeelcs two- 

 tbirds as broad as tbe eye beigbt, facial ridges nearly parallel, sides of tbe face 

 at narrowest part eacb as wide as tbe median depression. (]>. 132) EKthyprosopa. 



65. Abdomen subopaque, partly or wbolly covered witb pollen 66. 



Al)doinen sbiniug, destitute of i)ollen (p. 50) Mijiophania. 



66. Vibrissa' inserted at least tbe lengtb of the second antennal joint above tbe 



oral margin 67. 



Vibrissic inserted balf tbe lengtb of tbe second antennal joint or less above tbe 

 oral margin 70. 



67. Frontal bristles not descending below base of antenna' 68. 



Frontal bristles, at least two pairs, situated below base of antenna', vibrissie 



near middle of face, clieeks broader tban tbe eye beigbt. (I't. 138) Microphthahna. 



68. (Jbeeks less tban one-balf as broad as tbe eye beigbt, sides of face destitute of 



maciocba'ta' 69. 



Cbeeks almost as broad as the eye beigbt, sides of face bearing a row of macro- 

 cba'ta' (P- 51) rhi/lo. 



69. Small erossvein beyond tbe tip of tbe first vein (p. 80) Senotainia. 



Small erossvein far before tbe tip of tbe first vein (p. 138) Amohia. 



70. Tbird joint of antenna' at most but sligbtly longer than tbe second, sides of the 



face destitute of macrocba^ta' 71. 



Third joint more tban twice as long as the second, antennie two-thirds as long 

 as the face, sides of face bearing a row of macrocba'ta'. . . (p. 131) Brachycoma. 



71. Second joint of arista over twice as Icmg as broad (p. 143) Echinomijia. 



Second joint at most imly sligbtly longer than broad (p. 138) Amohia. 



72. Face bearing macrocba'ta) at least near lower ends of tbe eyes 73. 



Face destitute of macrocba'ta-, on its sides 76. 



73. Head at tbe vibrissa', as long as at base of antenuay^bird joint of antenna' less 



tban twice as long as the secimd 74:. 



Head at tbe vibrissa', much sborter tban at base of antenna- 75. 



74. Hind erossvein much nearer to tbe bend of tbe fourtb vein than to tbe small 



erossvein (p. 131) Braclnjcoma. 



Hind erossvein at most only sligbtly nearer to the bend tban to tbe small cross- 

 vein (p. 130) Tricogena. 



75. Facial ridges almost parallel, sides efface at narrowest part each nearly as wide 



as tbe median depression (p. 128) Opsidia. 



Facial ridges widely diverging below, sides of face oaeb less than one half as 

 wide as tlie median depression (p. 127) Meiopia. 



,^jC^ 



