Zool.— Vol. I.] CALVERT— ODONATA. 381 



7. Argia fissa Selys. 

 Plate XXV, Fig. ii. 



Argia fissa Selys, Bull. Acad. Belg., 2nd Ser., Tome XX, 1865, p. 401; 

 Kirby, Cat. Odon., 1890, p. 138. 



Male pale blue with the following black markings: antennae beyond the 

 second joint; a broken line enclosing an area corresponding to that of the 

 postocular spots of many species; a C-shaped mark, with the convexity 

 towards the median line, on either side of the middle prothoracic lobe, the 

 ends of the C connected with a narrow black margin to this lobe; two dorsal 

 spots on the hind prothoracic lobe; a mid-dorsal thoracic band; a humeral 

 stripe, at its lower end nearly as wide as the mid-dorsal, in its lower half one- 

 fourth to one-fifth as wide, still narrower in its upper half— the blue remaining 

 between the mid-dorsal band and the humeral stripe is somewhat narrower 

 than the former; a line on the second lateral thoracic suture; a small basal 

 spot on abdominal segment 1; on 2 a longitudinal stripe, on either side, which 

 at its apical end is bent at right angles and directed towards, but does not 

 reach, the mid-dorsal line, and a transverse, apical ring; a triangular spot on 

 either side of apex of 3-6, and a transverse apical ring which on 4-6 unites 

 with these spots; a similarly united ring and pair of stripes on 7, each stripe 

 prolonged on its side of the segment to the base; sterna of 3-10; femora 

 superiorly, tibiae inferiorly, tarsi entirely. 



Abdominal segment 10 with a mid-dorsal, apical, quadrangular excision, 

 as wide as deep, with a pale tubercle on either side. Appendages a little 

 more than half as long as 10, pale. Superiors, viewed from above, diver- 

 gent, apex somewhat blunt, outer side convex, inner side nearly straight; 

 viewed in profile, each is directed but slightly downwards, upper margin 

 more oblique than the lower, inner, lower margin with a small, pointed black 

 tooth directed downwards. Inferiors equal in length to the superiors; viewed 

 in profile, directed upwards, upper margin nearly straight with a slight trian- 

 gular excision near the base, lower margin first convex then concave, apex 

 truncated almost perpendicularly, produced as a slight tubercle at its lower 

 angle; viewed from below, the two inferiors are straight, parallel, of nearly 

 equal width throughout, apex truncated nearly at right angles to the long 

 axis of the body, lower surface blackish. 



Wings with a slight yellowish tinge. Pterostigma brown, surmounting a 

 little more than one "cell. Front wings with five antenodal cells, fifteen to 

 seventeen postcubitals, nodal sector arising near the seventh or eighth, ultra- 

 nodal at three or four cells more remote, upper side of the quadrilateral one- 

 fourth as long as the lower side. Hind wings with four antenodal cells, 

 thirteen to fifteen postcubitals, nodal sector arising near the sixth or seventh, 

 ultranodal at two to three cells more remote, upper side of quadrilateral two- 

 fifths as long as the lower side. 



Dimensions: Total length 42 mm.; abdomen 33 mm.; hind wing 25 mm. 



2 6" Tepic, Oct., 1894, Eisen and Vaslit. 



I compared these two males with specimens from Guate- 

 mala in Baron de Selys' collection, with which they agree. 



