182 Annals of the Carnegie Museum. 



of the segment, or merely an isolated, anteapical spot in the last fifth, 

 posterior five-sixths of the dorsum of 5, and nearly all of the dorsum 

 of 6-10, narrowing posteriorly on 9 and 10. Sides of 6-10 brownish 

 yellow. Appendages ochreous, slightly shorter than 10, conical. 

 A ventral posterior spine on 8. Genital valves not reaching to the level 

 of the hind end of the anal tubercle (nth segment), ochreous, their 

 palps blackish-brown. Pterostigma brownish-yellow. Hind margin 

 of prothorax directed vertically upward, instead of sloping upward and 

 caudad, as in the case of the c?. 



In the young 9 the head and thorax are brownish-yellow ; the pale 

 color of abdominal segments 1-5 is yellowish instead of red ; dark 

 markings on 1-10 dark metallic-green, instead of black. 



cJ 1 9 . Anal vein ( = inferior sector of the triangle of de Selys) 

 separating from the hind margin at, or distal to, the cubito-anal cross- 

 vein ( = basal postcostal of de Selys) on both front and hind wings. 

 Front wings with 8-9 (c?) or 9-10 (?) postnodals, 9 more frequent. 

 Hind wings with 6-7 (cT) or 7-8 (9 ) postnodals, 7 more frequent. 

 M 2 ( = nodal sector of de Selys) arising nearest the fourth postnodal. 



Dimensions: Abdomen cT 24-25,9 25; hind wing (^15.5-16.5, 9 

 17-18. 5 mm. 



Habitat : — Brazil, Chapada, by H. H. Smith, 6 c? and parts of 

 4 others, 1 9 and parts of 4 others, nos. 81 and 143. Carnegie 

 Museum, Pittsburgh. 



Sao Paulo, September 5 and 7, 1900 by A. Hempel, 1 d\ 1 9 • 

 Academy of Natural Sciences of Philadelphia. 



91. Oxyagrion hempeli sp. no v. 

 (Plate III, figs. 52, 53.) 



cT. Dorsal surface of head and of nasus black, an ill-defined reddish 

 spot on each side a little anterior to that occupied by the pale postocular 

 spots of allied genera. Genae, labrum, (and lower part of frons?), 

 pale blue. Labium and rear of head pale yellowish. 



Thorax reddish ; hind prothoracic margin low, convex ; a narrow 

 mid-dorsal mesothoracic stripe about three times as wide as the carina 

 on which it lies ; mes- and metepimera each with a rather broad pale 

 greenish-brown or pale olive band, possibly due to postmortem dis- 

 coloration. 



Abdominal segments 1-6 bright coral-red dorsally, the following 

 black : a fine transverse ring at the intersegmental articulations begin- 



