1935 ] 
Mimetic Flies 
99 
SOME MIMETIC FLIES, WITH THE DESCRIPTION OF 
TWO NEW SPECIES FROM NORTH AMERICA 
(SYRPHHL3E; DIPTERA). 
By F. M. Hull 
University, Miss. 
I have recently had occasion to mention the similarity of 
the lateral aspect of Cerioid flies to that of certain Hymen- 
optera. Since that time, I find two additional species that 
prove to be undescribed and are here presented. A Eumenid 
wasp, Eumenes bollii Cress., was discovered among the ma- 
terial from Dilley, Texas, from which P. reinhardi Hull was 
taken and is considered to be probably the “model” of that 
species. The resemblance, while not exact, is very striking. 
(Figs, e, f). In at least eight respects, the similarity bet- 
ween them is notable. (1) Position of abdomen; (2) simu- 
lation of folded wings; (3) pendulous antennae; (4) apical 
segments of antennae contrastingly colored; (5) pleural 
markings; (6) general coloration; (7) position of wings; 
(8) pedicellate abdomen. C. aldrichi, n. sp. laterally viewed, 
greatly resembles Spilomyia longicornis Loew. 
Cerioides aldrichi n. sp. (Plate 9, fig. 4) 
Characterized by fairly large size, yellow scutellum, poste- 
riorly bifid, large yellow spots in anterior corners of second 
abdominal segment and the prominent silver-tipped style. 
Not closely related to any North American species. Pre- 
dominating colors, yellow and black. 
Length 17 mm. Female. Vertex yellow, the deep black of 
the upper section of front and of vertex encroaching upon 
the yellow and dividing it narrowly in the middle . The div- 
ided surfaces of the yellow spots rounded. Lower front and 
entire face, save for a narrow basal margin to the antenni- 
fer and a narrow median stripe, shining yellow. Cheeks very 
broadly, and a slender margin along the front of the epis- 
toma, deep black. The facial stripe is dark brown and has 
