F. R. COLE 65 



Humeral and praescutellar callosities and upper part of the pleurae brownish- 

 yellow; above the coxae the pleurae are black, shining. Legs yellowish-brown, 

 including the front coxae; extreme base of the latter black; tarsi brownish; 

 ungues and pulvilli black. Tegulae honey-colored, without any perceptible 

 darker margin. Halteres with a brown knob. Abdomen brown, the hind mar- 

 gins of the segments white. Venter whitish-yellow; incisures darker. Wings 

 subhyahne; very slightly tinged with brownish before the apex, near the costa; 

 auxiliary and first veins brownish; the costa, beyond the junction of the aux- 

 iliary vein, is dark brown and a little stouter. A single male. 



"Among the described North-American species, 0. incultus O. S., alone has 

 the htuneri of a paler color than the thorax; but it is easily distinguished by its 

 large size, its brownish wings, etc." 



At least two other species {costatus and aedon) have the humeri 

 paler than the rest of the thorax.. This is a variable character, 

 Ogcodes aedon 



Oncodes aedon Townsend, Proc. Cal. Acad. Sci., ser. 2, no. 4, p. 607, (1895). 



"Very similar to Oncodes humeralis O. S.,*' but differs in the tegulae being 

 fuscous whitish with well-defined narrow dark brown margins. Wings without 

 apical brownish tinge. 



"Humeral and prescutellar callosities, and upper pleurae brownish-yellow. 

 Thorax and scutellum, and lower pleurae, brownish-black. Legs yellowish- 

 brown, tarsi darker. Head black, thorax with short yellowish pubescence. 

 Tegulae obscure whitish, or with a fuscous tinge, possessing a well-defined dark 

 brown border. Knob of halteres brown. Abdomen brownish, hind borders 

 of segments yellowish-white. Wings subhyaline, costal margin brown distally 

 and more yellowish basally. 



"This species differs from 0. pallidipennis Lw. in the blackish scutellum, 

 yellowish outer humeral callosities and pleurae, and more distinctly margined 

 tegulae. From O. melampus Lw., it differs in the yellowish humeral and 

 prescutellar callosities, yellowish pleurae and much smaller size and lighter 

 coloring. 



"Baja Purisima, Lower California, April. One specimen. Length slightly 

 more than 4 mm." 



A male specimen in the National Museum may be placed in 

 this species. Thorax black. Border of squamae not well defined. 

 Ogcodes niger new species (PI. XV, fig. 41.) 



9 . Body shining black, thus differing from all other North American 

 species. Occiput black and almost flat, very little swollen. Head longer than 

 usual and of different shape in this specimen at least; not sloping back. 

 Antennae whitish. Thorax with rather long brownish pubescence which has 

 gray reflections; the body color is plainly visible through it. Scutellum not 



i» Biol. Centr. Amer., Dipt., i, p. 164 to 165. 



TRANS. AM. ENT. SOC, XLV. 



