172 BULLETIN 31, UNITED STATES NATIONAL MUSEUM. 



distal Iialfof biud tibife blackish. Wings liyaline, basal portion a little 

 yellowish . 

 Ten specimens, Florida (Professor Riley), Georgia, Cuba. 



Eristalis albiceps. 



Eristalia ulhiceps Macquart, Dipt. Exot., ii, 2, 56, 41 ; Osten Sackeu, Cat. Dipt., 



131, note 221. 

 Eristalis senicidus Loew, Centur., vi, 63. 



Habitat. — Carolina (Macq.), Cuba (Loew), Florida, San Domingo! 



$ . Length, 8 to 9™"'. Black, opaque. Eyes pilose, contiguous in male. 

 Face concealed beneath white i)olleu and thick pure white pile, more 

 abundant and C()nsi)icuous on the frontal triangle. Facial stripe and 

 cheeks shining black. Antenna? obscurely reddish or ferruginous ; arista 

 bare. Dorsum of thorax clothed with yellowish-white i)ile in front, inter- 

 mixed with blackish behind ; in front of the suture with a conspicuous 

 grayish pollinose fascia, and on each side with an oblique spot reaching 

 from the root ot the wing backward toward the scutellum. Scutellum 

 yellow, base narrowly black, pile black. First segment of abdomen black, 

 outer angles yellow; second segment light yellow, with a narrow median 

 opaque black stripe not quite reaching the hind margin, a little broader 

 in front, where it connects with the semicircular black below the scu- 

 tellum ; third segment with an oval reddish yellow spot on each side, 

 confluent with the yellow of the preceding segment, the hind border 

 yellow, the black deep opaque without any shining spot or fascia ; fourth 

 segment with a yellow hind border, and a narrow interrupted shining 

 fascia dilated on the sides; hypopygium shining black with light pile; 

 pile on the opaque portions black, on the yellow spots yellow. Legs 

 black; hind femora dilated; knees, basal third of front and hind tibiaj, 

 basal half of the intermediate tibijie, and the middle metatarsi, light yellow, 

 the extreme base of the anterior metatarsi luteous. Wings hyaline, some- 

 times faintly clouded in the middle and outer parts; near the end of the 

 marginal cell there is a distinct curvature of the second vein into the 

 submargiual cell. 



9 . Differs in the presence of a complete grayish band on the dorsum 

 of the thorax in front of the scutellum, in the second segment of the ab- 

 domen being broadly opaque black in the middle, narrower in front and 

 extending as a fascia to the lateral margin of the abdomen behind; the 

 third and fourth segments have each, also, a narrow, interrupted shining 

 fascia, and the lower part of the front is not wholly white pilose. 



Baron Osten Sacken, after an examination of the type of albiceps, states 

 that it looked like seniculus of Loew. Macquart's description applies suf- 

 ficiently closely, excei)t the ''yeux this," which is probably an error, such 

 as he has also made in regard to other Xorth American species of this 

 genus. The description of seniculus applies fully to the specimens which 

 I have from Florida (two, Dr. Whitfield), Georgia (two, Professor Riley), 

 and San Domingo (three, Mr. G. F. Frazar). 



