200 Annals of the Carnegie Museum. 



ing veins, surmounting one cell, proximal edge more oblique than the 

 distal, posterior edge the longest, costal edge next in length. Anterior 

 side of the quadrilateral two-fifths (front wings) or three-fifths (hind 

 wings) as long as the posterior side. Front wings with 16 postnodals, 

 M 2 arising nearest the seventh; hind wing with 14 postnodals, M 2 

 arising nearest the sixth. Anal vein separating from the hind margin 

 distal to the cubito-anal cross- vein by a distance less than the length of 

 that cross-vein, which is situated nearer the second than the first ante- 

 nodal. 



The single individual at hand is pruinose on the ventral surface and 

 inferiorly on the sides of the thorax, on the coxae, and on abdominal 

 segments 9 and 10. 



Abdomen 50 mm., hind wing 27 mm. 



9 unknown. 



Habitat : — Brazil, Bahia, 1 tf. Museum of Comparative Zoology, 

 Cambridge, Mass. 



M. co7'nicauda is allied to Leptobasis macilenta (Rambur) Selys, 

 which probably is also a Metaleptobasis. The description of macilenta 

 refers to a much smaller insect (abd. 35, hind wing 19.5 mm.) with 

 fewer (12-13) postnodals, border of segment 10 deeply excised in 

 the shape of a broad V, and superior appendages thicker at the base 

 than elsewhere ; its habitat is no more definite than " Bresil." 



105. Leptobasis vacillans Selys. 



Leptobasis vacillans Selys, Bull. Acad. Belg. (2) xliii, p. 101. 1877. Calvert, 

 Biol. Centr.-Amer. Neurop. pp. 120, 385, pi. v, figs. 22-25. 1902, 1907. 



What appears to be this species, hitherto not recognized in South 

 America, is represented by specimens from Paramaribo having darker 

 colors on parts of the body, perhaps as the accompaniment of greater 

 maturity, than existed in material previously described. 



c^ 9 . Dorsum of the abdomen marked with bronze-green as follows : 

 hindmost fifth of 4 and nearly all of 5-7, except a narrow transverse 

 basal mid-dorsally interrupted yellow ring on each, and the hind end 

 of 7, which is reddish. One male, moreover, has most of the nasus 

 (leaving its free margin pale blue or green), the frons superiorly (but 

 not inferiorly) and the vertex superiorly blackish, the last with some 

 reddish reflection ; and on each side a moderately sized blue postocuiar 

 spot widely confluent with the blue of the rear of the head ; the other 

 male and one female have the head entirely reddish superiorly. The 



