FERNALD '. SPIIECIDAE FROM ARGENTINE. 271 



outer end of the inner cells. Outer margins of both pairs faintly fuliginous beyond 

 the cells. Cubital vein of the fore wing entirely obsolete beyond the third cubital 

 cell except for a very short stub. Subdiscoidal vein also with a short stub beyond 

 the second recurrent, but with a dark streak extending a short distance beyond. 

 Radial vein of the hind wing with a short stub and darker streak beyond the trans- 

 verse cubital. Cubital not extending beyond the transverse cubital. Veins brown, 

 the subcostal and anal of the fore wing, and the anal of the hind wing, almost black. 

 Tegulae dark brown, lighter behind, golden sericeous, almost pubescent except 

 near the hinder margin. 



Legs. Coxae and trochanters black. Fore coxae and trochanters slightly yel- 

 low sericeous, the former with scattered yellow hairs. The other segment of the 

 fore legs red, more or less sericeous, the last two tarsal segments darker than the 

 others. Claws dark brown. Middle and hind legs like the fore legs except for a 

 slight dark streak on the posterior side of the hind femora. Spines on all the legs 

 red. Fore metatarsus with eight comb teeth on the outer margin. 



Length, 31 mm. Expanse of wings, 40 mm. 

 t Described from one female specimen taken at Cordova, Argentine. 



This striking species closely resembles eugenia Smith, but differs from it in the 

 outline of the clypeus, the sculpturing of the dorsum of the median segment, and 

 in the distribution of color on the abdomen and legs. If this insect is subject to 

 much variation, it may prove to be Smith's species. 



Sphex fragilis (Smith). 



Twenty-three female, sixteen male specimens. Length : females, 15-23 mm. ; 

 males, 13-20 mm. 



" Common on the altos about the last of October on the yellow flowers of a 

 Cladrastis (Chanar)." Davis. 



This interesting series shows much variation in size and in the amount of red 

 present on the abdomen, but every gradation between the extremes is present, and I 

 am unable to make more than one species of the lot. Most of the specimens come 

 nearer suavis Burm. than to fragilis, but as the difference between the two as given 

 by Burmeister consists only in a larger amount of red in suavis, it would seem to 

 be simply a color variation. 



In all the specimens, at least the median dorsal surface of the last three abdomi- 

 nal segments is black. In many the black areas are broader, covering more of the 

 surface of these plates ; in others the black begins to affect the posterior ventral 

 plates and extends farther forward above, and this extension of the black proceeds 

 till in some specimens only the second segment of the petiole, the segment next 

 behind this, and the anterior margin of the next, are red, aud the base of the 

 second petiole segment is black or dark above. As the black increases in amount 

 it becomes more bluish in quality, as is called for by the description of fragilis. 

 None of the specimens show any tendency toward the appearance of monetcc 

 Smith, as mentioned by Fox (Proc. Acad. Nat. Sci. Phila., 1897, p. 374). 



