BY K. J. TILLY ARD. 717 



brown, almost black, bases quite black. Inferior short, 3 ram., 

 rather broad, terminated on each side by a short spike; convex 

 beneath; black (Pl.xxxiii., figs. 3-4). 



9. Total length 125 mm.; abdomen 94 mm.; forewing 78 mm., 

 hindwing 76 mm. 



Very similar to the male in coloration, differing as follows : — 

 Hindwings rounded. Abdomen broader and more cylindrical 

 than in male. Ovipositor large, blunt, reaching to end of 

 abdomen, upcurved, black, carrying two tiny filaments as in P. 

 gigantea female. Aj^pendages short, 15 mm., pointed, black; 

 separated by the large rounded anal projection of 10. 



Hab. — North Queensland; very rare : Cairns, Kuranda, Ath- 

 erton and Herberton. December-January. The type male was 

 taken at Herberton, the female at Kuranda. 



The two species, though closely allied, can be distinguished at 

 once by differences of size and coloration. The following points 

 should be specially noticed : — 



The expanse of wing in P. gigantea is (^ about 110 mm.; $ about 120mm. 

 ,, ,, P. ingentissima ^ 151mm.; 2 163 mm. 



The front of P. gigantea has a great deal more yellow on it than that of 

 P. ingentissima; this is shown clearly in the plate. The upper thoracic 

 markings are different in shape; gigantea having two well defined bands, 

 ingentissima a triangular area, formed by two short bands which narrow 

 very rapidly. The subtriangle of the forewings has 3 cellules in gigantea ^ 

 6-7 in ingentissima. The anal angle of the hindwings of the male is slightly 

 more pronounced in gigantea. The yellow markings of the abdomen are 

 very different; gigantea has the dorsal and lateral bands along nearly the 

 whole of the abdomen; ingentissima has but the beginning, of them on the 

 first two or three segments. Again ingentissima has transverse bands on 

 every segment except 1 and 10; gigantea has not. Finally, gigantea has the 

 9th segment bright orange-yellow; ingentissima has it nearly black. The 

 appendages on examination will be found to differ remarkably, as may be 

 seen in the plate : As regards the superior appendages, those of ingentissima 

 are broader, and less angulated on the inner margin; their colour, too, is 

 black, while those of gigantea are semitransparent brown : The inferior 

 appendages are very different both in form and coloration (see figures). 



In conclusion, the addition of this wonderful new species to 

 the list of Australian Odonata is of great interest, showing us, as 



