MEUOinS OF TEE QVEENSLAEB UUSEUE. 
JoO 
ICHTHYOLOGICAL NOTES (No. 2). 
By J. Douglas Ogilby. 
SELACHII. 
ORECTOLOBID^. 
In 1908 and .1909 two ini})ortant papers dealing with the orectoloboid 
sharks appeared ^ ; in both of tliese I was under the impression that the impossi- 
bility of recognizing tlxe family or indeed the genus HemisoylUum^ 
had been demonstrated be\u)nd (piestiou. T 'vvas, therefore, somewhat astonished 
lo find the family revived in 1918 iii a pa])er entitled ‘‘Tlie Hemisvyiiiid Sharks 
of the P]iilip])ine Archipelago.'’- But the ‘‘Key to the Genera of llemiscijUikhv,^^ 
therein defined is still more astounding, for I can not comprehend by what 
process of inductive reasoning the author divorces ParascylUiun from its natural 
allies Ginghjmoslonta and Xebrius, and Justifies its propinquity to ChiloscylUum, 
the two genera being near tlui apices of fbe Orectolobiihv. Furthermore 
ChUoscyllium can not logicaily be separated from Hiegostoma, of which it is the 
natural ally, even tiie extraordinary method of aiu^ioring the egg-case, described 
and figured by Ogilb.y and IMid.’uIloch,^ Ixnng common to the two genera. Perhaps 
Smith was misled by Brof. Garman's key to the Orcctolohido;,^ though that 
can not account for the Jettisoning of Stegostomu. But to any student of tliese 
sharks the Professor’s key itjust appear hopelessly artificial, and wholly hulking 
in the simplicity which is the chief unu'it of Regan’s arrangement and, there- 
fore. of ours Avhich was dev(9oped independently. And while 1 am on the subject 
1 may state that I see no reason, indeed xio expiauation is attempted, for the 
substitution of Ncbrode.P for Xcbrius^’ in Garman’s Plagiostomia. Again, the 
characters on which Garman depends to validate his Xebrodcs inacnincs have 
long ago been shown to be unreliable in this famil}^, and in fact our specimen.^ 
from Darnley Island, shows as many charat'ters of tlie iMauritian macnirus as of 
the Red Sea concolor-, his species, therefore, like his genus should sink into 
^ Regan, Proe. Zool. Soo. Lomlon, 1908, 347-304; Ogilby & McCullocli, Proe. Roy. Siui. 
X. S. Wales, xlii, 1909, pp. 204-299. 
“Smith, Proe. P. 8. Nat. ^lus.. xlv, 1913, pp. 507-o09. 
Ibid., p. 289. 
^ Mem. Mas. Ooni]). Zool., xxxvi. 1913, p. 43. 
^ Garman, ibid., ]). aO. 
” Ruppell. None tVirbelth. Abyss., Fiseli., 1838, p. 02. 
'Mem. Queensl. Atus.. ii, 1913, p. 90. 
