170 CALIFORNIA ACADEMY OF SCIENCES [Proc. 4th Ser. 



two Laguna specimens are from F. R. Cole, and two Santa 

 Barbara are marked "Dyar", but I have had tliem many years. 

 I collected all the rest, including some at Santa Barbara. Dates 

 of collection are of almost no significance. 



The species occurs in swarms on the castup seaweed of the 

 California seashore; I have had several thousands in my net at 

 once. It is the most abundant of the shore flies. 



6. Fucellia separata Stein. 



Stein, Wien. Ent. Zeit., xxix, 24, 1910. — Monterey, Cal, 

 and Seattle, Wash. 



Male and female : General ground color dark brown, with gray-brown 

 pollen. Front over one-third the width of the head, yellow above an- 

 tennae, bristles as in maritiina; antennae black, small, third joint only a little 

 longer than second, arista short, a little thickened on basal third ; para- 

 facial yellow-pollinose, narrow but very short on account of the peculiar 

 shape of the eye, which has its longest diameter almost lengthwise of the 

 insect and is short vertically, leaving a broad, yellow-pollinose bucca as 

 high as it is ; vibrissae high above lower edge of head ; palpi black, some- 

 times dark yellow at base ; proboscis small, black ; back of head bulging 

 and nearly bare. 



Thorax brown, opaque, a lighter pollinose streak from the inner part 

 of humerus back to root of wing, and a pale spot on side just below 

 humerus; chaetotaxy as in niaritiiiia, but with a few small, distinct hairs 

 bordering the humerus and suture and behind the latter, and stpl only 1-1 ; 

 calypters pale yellow, rim and fringe concolorous ; halteres yellow. 



Abdomen a little tessellated, in the female with no special characters ; in 

 the male the hypopygium is large, the fourth segment wide and declivous, 

 the fourth sternite strikingly large, prominent but bare ; first segment of 

 hypopygium dull brown, with numerous spiny hairs on hind part ; second 

 segment concolorous, concave in profile to a bifurcated hump just before 

 the anus; forceps dark yellow, wide, flat, and arched toward the median 

 line. 



Front tibia with one seta on front, generally one small on outer hind 

 side ; middle tibia with one on outer front, one on outer hind, and in the 

 female there are also one or two each on inner front and inner hind, which 

 are generally absent in male ; hind tibia with two on hind, two on outer 

 hind, three on outer front ; middle femur in male with a row of small 

 bristles on lower front edge, showing but slightly in female ; hind femora 

 plain in male, with row of bristles on outer upper edge in both sexes, and 

 one smaller on lower outer edge in male, which is but little developed in 

 female. 



Wing subhyaline, costal spine rather distinct, other costal setules present 

 but small. 



Length 4 to 4^ mm. 



One hundred specimens, both sexes ; 65 collected by myself 

 at Pacific Grove, Santa Barbara, Long Beach, and San Diego. 

 Cal, and 35 by Professor Melander at Bwaco, Wash., in 1917. 



This is the second species in abundance on the California 

 coast, ranking next to rufifibia. 



