Vol. XXVli] ENTOMOLOGICAL NEWS. 355 



discovery of the species in some of de Selys' material not sur- 

 prising. The species is a pond or sluggish stream inhabitant. 



In Calvert's key to females of Acanthagrion (Ann. Carnegie 

 Museum, vi, Odonata Neotropical Regioli, p. 162), ascendcns 

 runs out to C, under B, under A, in which also will fall A. 

 kennedii described below. The female of ascend ens may be 

 recognized at once by having the mesepisternal fossae at about 

 the midheight of the mesepisterna, the carina between the 

 fossae, as seen in lateral view, elevated into a small semi- 

 circular prominence. In "gracile" and kennedii the fossae are 

 placed much lower, the carina not elevated but bevelled off 

 anterior to the fossae. 

 Acanthagrion "gracile" Rambur (Plate XVII, figs. 9, 12). 



In view of Mr. Kennedy's work on Acanthagrion penes.* and 

 because of the specific distinctness of forms otherwise scarcely 

 separable, the true status of gracile and the many varieties dis- 

 cussed by de Selys is a matter for future determination. The 

 following notes refer to the common Central American form 

 determined by Calvert as gracile (Biol. Centr. Amer. Neurop., 

 pp. 115, 382). 



$ : In the darkest specimens the dorsum of the head is entirely 

 black excepting the blue postocular spots and a more or less definite 

 blue trace on the occipital crest; in the palest, the pale color on the 

 anterior side of the first joint of the antenna is produced inward and 

 upward to make a rounded connected spot on the frons above on either 

 side; back of and just outside this is a spot opposite the apical end of 

 the second joint of the antenna, and another spot between the apex of 

 this second joint and the eye ; between the median ocellus and the sec- 

 ond joint of the antenna is another spot lying close to the ocellus.. 



On the middle lobe of the prothorax the blue spot on either side 

 varies considerably in size. The black spot on the second lateral su- 

 ture above is often inconspicuous, though always present so far as 

 the present collection goes, but never produced as a line beyond the 

 depression in which it lies. 



In the extent of black on abdominal segment I there is considerable 

 variation, and but little variation on 2; the black on I is basally about 

 as wide as the black generally on 2, but on I the blue on either side en- 

 croaches subapically on the black in a triangular dorsal projection, 

 which may fail, in varying degrees, to reach the mid-dorsal line or 

 which may broadly meet its fellow of the opposite side, in which case 



*See this volume of the NEWS, pages 325-330. 



