ART. 6. STUDIES ON LEUCOSPIDINAE C. J. WELD. 7 



by about nine smaller and often irregular teeth (pi. 2, fig. 12). In 

 slossonae^ on the other hand, there are but five large teeth, the first 

 two long and sharp, the next two more blunt, and the last a broad 

 3-dentate tooth (pi. 2, fig, 10) ; still another arrangement of teeth is 

 shown in fulighiosa (pi. 2, fig. 11), where the basal tooth is small and 

 inconspicuous, the following five increasing in size with a broad 

 4-dentate tooth toward apex. The wings vary from hyaline to dark 

 fuliginous in color, the subcostal and postmarginal veins are promi- 

 nent, the radius and its branches short, leaving radial and cubital 

 cells undeveloped, and there is only a trace of the median vein and 

 its branches (pi. 1, fig, 2). 



Abdomen. — The abdomen in Leucosj)is is composed of eight tergites 

 not including the propodeum. The first is a narrow inconspicuous 

 ringlike segment which forms a short constricted portion between 

 the propodeum and the first apparent (second) tergite; this second 

 tergite, which in some species is the longest, is always well developed 

 and frequently has distinct sculpturing on its dorsal surface; the 

 third and fourth tergites are usually constricted and telescoped to- 

 gether so that often the third is completely hidden but may be seen 

 as a short segment in certain species, as for example in gigas and 

 indiensis (pi. 3, figs. 15 and 19), while in affinis it is seldom visible 

 except in dissection (pi. 1, fig, 3) ; the fourth and fifth tergites to- 

 gether are not as long as the second, while the sixth is usually the 

 largest segment occupying most of the space between the constriction 

 and the small crescent shaped spiracle-bearing seventh tergite; in 

 cayennensis the sixth segment is about equal to the fifth and much 

 shorter than the second, a proportion which is exceptional (pi, 3. 

 fig. 17) ; the eighth tergite differs greatly in structure according to 

 sex; in the female it forms a broad rounded portion, which consists 

 of two similar halves reaching from near base on ventral side around 

 apex, inclosing the ovipositor and its appendages which project from 

 its tip (pi, 4, fig, 22) ; in the male the segmentation of tergites is 

 less distinct than in the female, with more or less fusion between 

 fourth, fifth, sixth, and seventh segments, and a small semicircular 

 eighth segment at apex (pi. 4, fig. 26) ; the basal sternites in the 

 female are short and inconspicuous, the hypopygium, which tapers 

 toward its tip and is angled along median ventral line, occupying 

 most of the ventral surfaces (pi. 1, fig. 1) ; the sternites in the male, 

 on the other hand, are quite distinct (pi. 4, fig, 25), As a whole 

 the male abdomen is more flattened and tapering toward the apex 

 than the female. The ovipositor varies in Leucospis from a short 

 upright spur near apex of abdomen to a long slender shaft which 

 turns forward over the dorsum as far as the scutellum. 



