234 NEW FORMS OF AUSTRALIAN ODOXATA, 



triangular basal sublateral spots; 4-6 with a transverse basal 

 band; 7 with a dorsal basal mark of irregular shape, with its 

 apical point lying nearly at middle of segment, and followed by 

 a remnant of the dorsal line; a yellow transverse line in suture 

 between 7 and 8; large irregular sublateral spots on 7-9; 10, 

 black Appendages: superior 1*8 mm., parallel, straight, 

 cylindrical to near tips, which are sharply pointed; colour yellow, 

 with bases and tips black; underneath, close to bases, each carries 

 a small black hook projecting downwards and curved inwards 

 behind the hooks of the inferior appendage : inferior # 6 mm., 

 black, consisting of two widely separated upturned hooks. (Plate 

 xv., figs. 3-4). 



Q. Total length 42, abdomen 31, foreiving 24, hindwing 23 mm. 



Differs from the male as follows : Wings much saffroned from 

 base to nodus; pterostigma 2-7 mm., black line in suture above 

 clypeus generally absent or obsolescent. Head and thorax marked 

 as in (J. Occiput with two pairs of prominent black tubercles, the 

 outer pair narrow, rather truncate, with a small yellow spot near 

 middle ; the inner pair wider, more rounded at tips, slightly hooked 

 (Plate xv., fig. 6). Two yellow lines on metafemora. Abdomen : 

 1-2 swollen, 3-10 fairly cylindrical, marked as in <J, but with dor- 

 sal mark of 2 much wider and dorsal lines of 3-6 more distmct; 8 

 with a basal yellow triangular patch running out apically into a 

 fine dorsal line, on each side a sublateral band ; 8-9 black, with sub- 

 lateral basal spots, lying on the narrow projecting shelves of the 

 two segments, formed by the tergites slightly enfolding the ventral 

 parts; 10 black. Appendages 0-8 mm., yellow, subcorneal. 



Hub. — Murray River, at Morgan, South Australia. December. 

 Taken by Messrs. S. and F. Angel, of Adelaide, to whom I am 

 indebted for a series of five males and six females, taken between 

 1909 and 1912. 



Types: $Q Coll. Tillyard (<J, December 28th; £ ; December 

 27th, 1909). 



1 know of no other locality for this interesting and very distinct 

 species, which I have much pleasure in naming after its discoverers, 

 who took, at the same locality, the somewhat rare Austrogomphus 



