334 MR. G. KREFFT ON AUSTRALIAN CROCODILES. [Mar. 18, 3. Remarks on Australian Crocodiles, and Description of a Ne\r Species. By Gerard Krefft, F.L.S., C.M.Z.S.* [Received February 17, 1873.] About a year or two ago I sent to Dr. Gray the photograph of a Crocodile's skull, which he examined and considered tobeundescribed. Tbe name of Tomistoma krefftii was proposed for it ; but I cannot find the description in any of the works at my disposal. During the process of cleaning and bleaching the skull, it was in-jured by rats, and the end of the snout is now broken and some teeth lost ; otherwise it is in tolerable condition, and appears to agree with Croeodilus schlegelii, as figured by De Blainvdle (Osteographie, Atlas, vol. ii. pi. 5), with this difference, that the mandibular sym-physis extends to the 1 5th tooth in C. schlegelii, and to the 6th tooth only in T. krefftii (Gray). There are 18, or perhaps 19, teeth above, and 1 5 teeth below, on each side, a notch being observed be-hind the 4th (or 5th) tooth, with a small pit for the lower canines. * Tbe following letter, referring to tbis paper, has been addressed to tbe Se-cretary by Dr. J. E. Gray, F.E.S. :— Sir, — Mr. Erefft has just sent to me the photograph of a Crocodile from Aus-tralia, which he has named Croeodilus johnsonii, with the request that I would communicate to the Society some observations upon it. Tbe photograph is about 22 inches long, and represents the dorsal view of the animal. There is no doubt that it represents a species of Crocodilida, from the form of the cervical and nuchal shields ; but in many respects the beak is similar to that of Tomistoma, the Bornean Gavial. The beak is more slender than in any tvpieal Crocodile of tbe Old World that has occurred to me. It is somewhat like that of Molinia intermedia, from tbe Orinoco, figured in the Trans. Zool. Soc. 1869, vi. p. 151. f. 4, 5, and pi. 32. f. 4^6 ; but it differs from that species in the beak being more slender, not being swollen on the sides, or so broad and circular at tbe end, and also in the shields of the neck and back, which are very different. In many respects the appearance of the animal, and the form of the beak, are much like (especially in the want of dilatation at tbe sides, and in the moderate breadth of the end) those of the African false Gavial, Mecistops cataphractus; but it has well-developed lateral cervical shields, which are wanting in all tbe African specimens I have hitherto observed ; and one cannot understand how a West-African Crocodile can have been taken to or found in Australia. Judging from the photograph, I believe it to be a new species of Crocodile ; and the form, as far as I know, is peculiar to Australia. I am, Sir, Tours truly, Joh>" Edw. Grat. P.S. — I strongly suspect that tbe photograph of the head for which Mr. Krefft says I had proposed the name of Tomistoma krefftii belongs to Croeodilus john-sonii. The examination of a photograph of the upper part of the head would induce one, on account of the slender conical form of the beak and tbe absence of large canine teeth, to consider it a species of Tomistoma ; but the examination of the photographs of the skin, showing the eight cervical plates separated from the dorsal shield, and the short symphysis of the lower jaw, mentioned by Mr. Krefft, show that it is a Crocodile, and not a Gavial.
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