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No sort of Sirenoidcb has been yet found in the southern parts 
of Australia, and as those known are all from tropical regions, it 
is not very probable that any do inhabit them. 
Mr. Krefft has made known a sort of Geratodus (Fosteri), 
found in Queensland by Mr. Masters, which probably belongs to 
this family. 
Dr. Gruuther, with his usual urbanity, says that I have made 
some additions to the synonymy of the Lepidosirens in my work 
on the animals of South America ; I think that I have done 
something more, in making better known the singular dentition 
of those animals, in pointing out the curious anomaly they 
present in the want of symmetry of the position of the anus, 
which is not situated on the median line of the body, but on its 
right side. The learned doctor declares also that my Dissimilis 
is the same as Faradoxa ; but as of each there is only, if I 
am not mistaken, one specimen known (at least this was the 
case some few years ago), and as they are in very distant 
museums, I do not believe he has compared them ; I even doubt 
very much if he has ever seen one or the other. 
Sub-Class III.— 3ANOIDEI. 
“Not yet discovered in Australia.” 
Sub-Class IV.— CHONDROPTERYGII. 
“Skeleton cartilaginous; skull witli sutures. Body 
with medial and paired fins, the hinder pair abdomi- 
nal; caudal fin with produced upper lobe. Gills 
attached to the skin by the outer margin, with 
several intervening gill-openings ; rarely one gill- 
opening only. No gill-cover. No air-bladder. Three 
series of valves, in the bulbus arteriosus. Intestine 
with a spiral valve. Optic nerves commissurally 
united, not decussating. Ovaries with few and large 
ova, which are impregnated, and, in some, developed 
