FLIES OF THE GENUS ODINIA — SABROSKY 233 



yellow; whole front rather evenly gray pollinose, the orbits and 

 frontal triangle not sharply distinct; upper half of face broadly seal 

 brown from eye to eye, the lower half silvery white on yellow ground 

 color; second antennal segment black, the dorsal two-fifths com- 

 pressed and whitish, third antennal segment with broad black stripe 

 on both inner and outer surfaces; arista black, yellow basally; mes- 

 onotum with irregular brown spots about bases of bristles, and 

 smaller spots about bases of hairs, but no median brown stripe, the 

 spots especially large about bases of second to fourth pairs of dorso- 

 centrals; mesonotum anterolaterally on each side with a weak brown 

 stripe mesad of humerus and extending caudad to notopleuron 

 through base of presutural bristle; mesopleuron gray above, or with 

 faint trace of brown near posterodorsal angle, but not with brown 

 stripe; lower rim of mesopleuron and upper margin of sternopleuron 

 dark brown; second abdominal tergum without a brown band, and 

 the four brown spots on each of terga 3 to 5 small, rounded, and well 

 separated from each other; legs about as described for biguttata; wing 

 as in figure 7, with numerous black or black-brown spots scattered 

 over the wing, most of them outlined by a white corona caused, at 

 least in part, by fewer and paler microtrichiae in the surrounding 

 membrane; halteres whitish yellow. All bristles and hairs black. 



Front at vertex broader than long, twice the width of an eye and 

 half the width of head, with a few fine hairs on the frontalia and 

 lower orbits but none between the posterior orbital and vertical bristles; 

 vibrissa short, strongly curved, broadly flattened on basal half, the 

 adjacent orbital bristle or two likewise broadened basally. Mid 

 tibia with two strong, subequal apical ventral bristles; hind femur 

 v/ith one strong, preapical, anteroventral bristle. Length of body 

 and of wing, 3-3.5 mm. 



I have seen the following material: 4 females (USNM), Isla Santa 

 Cruz, Galapagos, 1948, K. Vinton; male (AMNH), Wollebaek Gald- 

 pagos-Expedition, 1925; male and female (AMNH),Barrington Island, 

 Galapagos, Oct. 20, 1925, F. X. WilKams. 



The specimens agree with the original description in all details 

 except in having five pairs of dorsocentral bristles, the normal number 

 for the genus, whereas the description said four pairs. This was 

 undoubtedly an error. 



The figures of williamsi by Curran are approximately correct, but 

 the figure of the head fails to show the broad flattening of the vibrissa 

 and one or two oral bristles, and also lacks strong divergent post- 

 verticals. In the specimens before me, the wing shows whitish areas 

 around the dark spots over the whole wing, and not merely along 

 the posterior margin, as shown in the figure. 



