382 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser. 



8. Argia pulla Selys. 



Plate XXV, Fig. 4. 



Argia pulla Selys, Bull. Acad. Belg., 2nd Ser., Tome XX, 1865, p. 410; 

 Kirbv, Cat. Odon., 1890, p. 139. 



The following description is based on 19 males and 9 

 females of the first of the lots mentioned below: — 



Male violaceous with the following markings very dark metallic green or 

 black: a transverse stripe across the top of the head from eye to eye, filling 

 the space between the three ocelli; posterior face of second antennal joint 

 and the whole of the following joints; often a line on the fronto-clypeal and 

 on the clypeo-labral sutures; greater part of the rear of the head, except for a 

 narrow stripe along the edges of the eyes inferiorly and a circular area around 

 the posterior foramen; a mid-dorsal band on the middle and the hind protho- 

 racic lobes and a narrow marginal stripe on the middle prothoracic lobe; a 

 mid-dorsal thoracic and an almost equally wide humeral band, the former 

 being equal in width at its lower end to the mid-dorsal prothoracic band, but 

 is narrower above; the humeral band encloses a violaceous spot at its upper 

 end and then fills the area between the humeral and first lateral sutures, or it 

 is narrowed to the humeral suture at its upper end and encloses no spot — 

 the violaceous color which remains between the mid-dorsal and the humeral 

 bands is equal in width to the latter; a complete line on the second lateral 

 suture and marks in the grooves on the pectus; basal half of abdominal seg- 

 ment 1 ; on 2 a longitudinal band each side, curved towards its fellow near 

 the apex of the segment; greater part of 3-7, except a narrow, transverse, 

 basal ring, and inferiorly on each side a longitudinal pale streak confluent 

 with this ring; an apical longitudinal band each side of 8, sides of 10 entirely, 

 9 usually like 10 but in some as 8; sterna of 3-10; the legs, except the coxa 

 and the tibae superiorly. 



In young males the violaceous color is not yet developed, but is preceded 

 by pale blue, and the dark markings are less extended, the legs pale, femora 

 with two superior dark stripes. 



Superior appendages pale, shorter than 10, directed outwards and down- 

 wards (in fig. 4 the superior appendage has been pushed up to show the infe- 

 rior appendage more clearly), apex bifid; above each superior appendage is 

 a large pale tubercle. Inferiors darker, longer, and larger than the superiors, 

 but not quite as long as 10; viewed in profile each is directed slightly upwards 

 and ends in three tubercles of which the most dorsal is received between the 

 two tips of the bifid superior appendage of the same side, while the other 

 two tubercles form the apex of the appendage, the inner ventral being the 

 largest and broadest of the three and often minutely denticulated. 



Wings with a very slight yellowish tinge. Pterostigma dark brown, sur- 

 mounting very slightly less than one cell. Three antenodal cells. Front 

 wings with twelve to fifteen postcubitals, nodal sector arising from the sixth 

 to between the seventh and eighth. Hind wings with ten to thirteen post- 

 cubitals, nodal sector arising at the fifth or sixth (at the seventh in one wing 

 of one male). 



