340 



A SUPPOSED INCIDENTAL OCCURRENCE OF A SUCKER 

 FISH {ECHENEIS AUSTRALIS, Bennett) IN AUSTRALIAN WATERS. 



By Edgar E. Waite, F.L.S., Director S.A. Museum. 

 \C ontrihution from the South Australian Museum.] 



[Read June 10, 1915.] 



Plate XI. 



ECHENEIS AUSTRALIS, Beilliett. 



Echeiieis austraUs, Bennett, Narr. Whaling Voy., ii., 1840, 

 p. 273. 



Echeneis scutata, Giinther, Ann. Mag. Nat. Hist. (3), v., 

 1860, p. 401, pi. X., fig. B; and Cat. Fish, Brit. Mus., ii., 1860, 

 p. 381; Liitken, Vid. Medd. Kjobenh, 1875, p. 42. 



liemilegia ausfralis. Gill, Proc. Acad. Nat. Sci., Phil., 1864, 

 p. 61; Jordan and Evermann, Bull. 47. U.S. Nat. Mns., iii., 1898, 

 p. 2270. 



JJfscriptio)!. — V>. ix. ; D. xxvi. 22; A. 24: V. i. 5; 

 P. 22 dex., 24 sin.; C. 13-^6. Length of head, 3*5 ; depth 

 of body, 7'86; and length of caudal, 4'9 in the length; 

 diameter of orbit, 9*9; of eye. 15'6; interorbital width, I'b; 

 and length of snout, 2'06 in the head; width of body between 

 the pectorals, 4'3 ; length of disc, 2'0 in the body, or 2*4 

 caudal included ; width of disc, 2*19 in its own length. 



Sucker. — The disc, which is relatively larger than in 

 any other species of the family, is slightly broader behind 

 than in front; it extends as far forward as the margin of the 

 upper jaw and overhangs the head and body at the sides. 

 The anterior lamellae extend to within twice the diameter of 

 the eye of each other in front, but the posterior pair are 

 widely separated, and leave a considerable portion of smooth 

 skin between and behind them; each lamella is beset v/ith 

 small spines; the free portion of the posterior edge of the 

 disc equals half the length of the snout and extends beyond 

 the extremity of the adpressed ventrals. 



Fins. — Regarding the sucker as the modified first dorsal, 

 the second fin originates at a point nearly half its own length 

 behind the disc; the highest rays are in the anterior fourth 

 of the fin, whence they rapidly diminish. The relative posi- 

 tion, size, and shape of the anal is almost exactly that of 

 the second dorsal, and neither reaches the caudal. The ven- 

 trals are pointed*, the first ray being the longest ; they can 

 be received into a groove, and are placed one-third the length 



