474 DRAGONFLIES FROM AUSTRALIA AND TASMANIA, 



black, the basal joint very short, only about one-fifth as long as 

 the very long and thin second joint. 



Thorax: prothorax dull yellow edged with dark brown; 

 posterior border edged with lemon-yellow. Synthorax brilliant 

 metallic green above, also on sides of mesothorax; a pair of pale 

 yellow humeral rays present; sides of metath(H-ax lemon-yellow, 

 with a rectangular patch of metallic green running forward for 

 2*5 mm. beneath hind wing. Xotum dark green, with pale yellow 

 spots on scuta. Legs with the coxie, trochanters, and bases of 

 femora in fore and middle legs pale yellow; the rest of the femora, 

 the tibi?e of forelegs, and all the tarsi black; tibite of middle legs 

 mostly brownish; hindlegs all black, except the dark brown tibiye. 



Abdomen very slender, 1-2 and 8-10 slightly widened; 

 width at segs. 5-6 only 0*6 mm. Colour metallic gi-een, pale 

 yellow on sides, especially on 1-2. 



Appendages: super io7' 1*4 mm., black, forcipate, shaped 

 as shown in Plate xxiii., fig. 12; each appendage carries a large 

 inner basal tooth, a second tooth ventrally placed at about half- 

 way (not visible in figure), and a third large tooth on inner 

 margin, at about one-fourth of the way from the tip. (Contrast 

 the same appendages in S. iceyersi^ Plate xxiii., fig. 11). Inferior 

 very short, blunt, rounded. 



5. Total length, 51*5; dbdomeii, iO: Joretcing, 31*5; hinchcing, 

 30 mm. Closely resembles the male, from which it differs only 

 in the shorter and thicker abdomen, and the longer and slightly 

 wider wings, with slightly larger pterostigma. Segs 8-9 of ab- 

 domen much swollen, 10 very small and narrow; appendages 0*3 

 mm., pointed. 



Differs from S. iveyersi Selys, by its much slenderer build, 

 smaller size, narrower wings, with Mo leaving Mj nearly half-way 

 betw^een nodus and pterostigma, the latter structure being black, 

 and much shorter than in S. iveyersi', antennje without any yellow 

 on the basal joint, which also is smaller than in -b'. iveyersi; 

 superior appendages of male differently shaped from those of S. 

 weyersi. 



Types in Coll. Tillyard (Hornsby, March 31st, 1917). 



