NO. 1938. THE DIPTEROUS FAMILY PUORIDM—MALLOCH. 455 



backwardly directed bristle, but in the specimen before me I can not 

 detect the usual short bristles, abdomen yellow, first segment with 

 the disk, second segment with lateral and posterior margins narrowly, 

 and remaining segments entirely darkened, venter yellow, second 

 dorsal segment with 2 to 3 bristle-like hairs; legs entirely yellow mid 

 tibial setulse distinct, hind tibial setulae (9-10) large and distinct, the 

 terminal one at apex especially so; costa to middle of wing, first 

 division rather longer than second, but not longer than second and 

 third together, third about one-fourth as long as second, fringe about 

 three times as long as diafneter of costa, fourth vein leaving at fork of 

 third, very slightly curved at origin and running nearly straight to in 

 front of wing tip; knob of halteres yellow, pedicel darkened. 



Length, 2 mm. 



A species that may fall easily into that section with only two scutellar 

 bristles, and very probably the male has only two. It is quite dis- 

 tinct from any of the other species that I have seen either here or in 

 Europe. 



Locality. — Arroyo, Porto Rico, February, 1899 (A. Busck), one 

 female. 



Type.— C&t. No. 14853, U.S.N.M. 



APHIOCH.ffl;TA SPINIFEMORATA, new speclw. 

 Plate 36, fig. 4. 



Female. — Yellow; frons yellow, about one-half broader than long, 

 only the ocelli black, one pair of very long and strong post-antennal 

 bristles, rather widely placed, divergent, first row of frontal bristles 

 very low down and forming a convex line with the post-antennal pair, 

 the space between them being much less than that between the center 

 one and the post-antennal, second row nearly straight, midway 

 between the ocelli and the post-antennal bristles, antennae rather 

 large, yellow, slightly darkened at insertions of arista, arista distinctly 

 thickened on basal joints, the apical portion very thin and nearly 

 bare, palpi yellow, of good size, and strongly bristled; the two bristles 

 below the eye very prominent; thorax darker than frons, with the 

 usual bristles, mesopleuras with one very strong backwardly directed 

 bristle, the usual small bristles absent, scutellum with two weak hair- 

 like bristles in addition to the two large marginal bristles posterior 

 to them, abdomen broad, more or less suffused with black-brown 

 laterally and posteriorly, except the sixth segment, and the usual 

 narrow hind-marginal bands which are yellow, second segment 

 slightly elongate, sixth elongate and rather conical, all segments with 

 2 to 3 strong lateral, marginal bristles, ovipositor exserted, somewhat 

 similar in size and shape to that of conica, not chitinous; legs yellow, 

 the apices of hind femora darkened, bristles on coxse and legs strong, 

 hind and mid femora with row of bristles on ventral surfaces, three or 

 48702°— Proc.N.M.vol.43— 12 30 



