212 British D7'agonflies. 



line. Occiput short, hind angles rounded and with 

 poHshed bands on upper side ; a poHshed spot on each 

 side of the mecHan Hne ; hind border notched. OcelH 

 incHcated. Anterior portion of vertex semicircular. 

 Antenna; short, not extending beyond the eyes ; seven- 

 jointed, third joint longest. Mask extending between 

 middle legs, stout ; length greater than breadth ; 

 enlarged gradually forward ; middle third somewhat 

 produced, cleft in middle, with comb of hairs. Palpi 

 broad, straight, cut square at end and jDroduced only 

 slightly in end hooks, finely denticulated. Movable 

 hooks sharp and bent, thin, just reaching the base of 

 their opposite. Prothorax not as broad as occiput, hind 

 border rounded. Processes enclosing an acute angle, 

 anterior one half length of posterior, both sharp. (Pig. 

 19, No. 7.) Legs rather slender, hind-legs longest, 

 extending to eighth segment ; femora somewhat arcuated ; 

 two faintly-marked pale rings on lower portion of femora. 

 Wing-cases extending to fourth segment. Abdomen 

 stout, very convex above, tapering from the middle to 

 the tip, smooth ; two parallel dark dorsal bands best 

 defined at beginning of segments. Lateral spines on 

 segments 6 to 9, strong, last shorter than segment 10. 

 Appendages sharp, long as the last two segments ; 

 lateral inferiors longest, lateral superiors two thirds the 

 length of middle, middle nearly or quite straight at tip. 

 Male projection stout, blunt, triangular, angular, half 

 length of lateral superior appendages. Female \cntral 

 valve reaches end of segment. (L. Cabot, " The 

 Immature State of the Odonata," Part IL Memoirs of 

 the Museum of Comparative Zoology at Harvard 

 College, U.S.A., 1881). 



