477 



^A Revision of the Genus Aracana and its Allies. 



By Allan R. McCulloch, Zoologist, Australian Museum, 



and 

 Edgar R. Waite, Director, South Australian Museum. 



\Co7itrihufion from the Australian and South A'usfralian 



Museums.^ 



[Read October 14, 1915.] 

 Plates XVI. to XXV. 



The paper results, primarily, from an examination of the 

 iishes obtained during the cruise of the trawler ''Simplon" 

 in the Great Australian Bight, and of which a more general 

 account appears in the preceding pages (pp. 455 to 476). The 

 Aracana e in the Australian and South Australian Museums 

 have also been examined, and others obtained by the col- 

 lectors of the ill-fated Federal trawler ''Endeavour" have 

 likewise been reviewed. 



In all ninety-three specimens have been examined, which 

 p)rove the several species to be exceedingly variable in form 

 and colour-marking, in the development of the spines on the 

 ■earapace, and in the ornamentation of the scutes. We recog- 

 nize five genera, of which one is new; the others were defined 

 by Kaup in 1855, but were later united with Aracana, Giay, 

 iDy Giinther, which genus he further regarded as a 

 subgenus of Ostraciou, Linnaeus. The species of the genera 

 Capropi/gia, Caprichthi/s, Kentrocapros, and Anoplocapros 

 are easily separated, but those of Aracana are not so readily 

 determined. 



Key to the genera allied to Aracana. 



<a Back elevated into a ridge. 



h. Tail encircled by a bony band, which may 

 be incomplete in the young. No supra- 

 orbital spine. 

 'C. Each lateral ridge of carapace with a 

 single, large, straight spine, which is 



broad and flat Capropygia 



cc. Lateral ridges Avithout, or with several 



small spines Anoplocapros 



bh. Tail not encircled by a bony band. Eiach 

 lateral ridge with a single recurved 

 spine, which is broad and flat. Supra- 

 orbital spine present or absent Caprichthys 



