Page:Quarterly Journal of the Geological Society of London, vol. 26.djvu/774

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outer or upper margins of both flanks might reach to the dorsal region, covering up and enclosing the ribs, exactly as is the case with the specimen before us. The perfect imbrication and close interlocking of the scales would undoubtedly conduce to this end by maintaining their compact order.

This seems to us so natural an explanation of the phenomenon, that we gladly adopt it ; and thus we find the greatest difficulty of the problem turned and conquered. We are also indebted to the liberality of Prof. Huxley for pointing out to us the affinity of our new form to Dasyceps, also a Permian Labyrinthodont.

The relationship to the latter is seen in the form and ornamentation of the head. In Dasyceps the muzzle is not by any means so much produced as it is in Lepidotosaurus ; the form, however, of the occipital region presents considerable resemblance. But what is most remarkable is that the surface of the skull is covered with minute, sharp, tooth-like processes, quite similar to those before described on the muzzle and sides of the skull of our new form.

The Bradford fossil recently described by Prof. Huxley in the Quart. Journ. Geol. Soc. vol. xxv. p. 309, under the name of Pholiderpeton scutigerum, shows some relationship to Lepidotosaurus in the large development of the ventral scutes ; but they differ greatly in character from those of the latter.

The extraordinary characters of the scales, their vast development, peculiar ornamentation, and perfect mode of imbrication, as well as the greatly elongated, narrow muzzle, and other characters of the head, make it necessary to establish a new genus for the reception of the Midderidge Labyrinthodont, to which, as previously stated, We have given the name of Lepidotosaurus Duffii, the specific name being in honour of the gentleman who has added so much to our knowledge of the vertebrata of the British Permian rocks.

EXPLANATION OF PLATE XXXVIII.

Fig. 1. Slab exhibiting the left side of Lepidotosaurus Duffii, two-thirds natural size : — a, a, a', line of the vertebral column ; a', the cervical portion of ditto ; b, the inferior portion of the skull ; c, small piece of the upper wall of ditto bulged inwards ; d, muzzle exhibiting at the sides minute conical tooth-like processes ; e, e, e, ribs ; f, belt of bony matter, resembling a fragmentary breast-bone ; g, g, anterior mass of bony matter, supposed to be the remains of the shoulder-girdle ; h, posterior ditto, nature undetermined ; i, i, inside view of the rows of dermal scales ; j, the dorsal extremities of four or five of ditto ; k, impressions of the anterior or lower extremities of four or five rows of scutes of the right side, showing the ridges and furrows and the minute striation of the surface ; l, l, patches showing the striated impressions of scales.

Fig. 2. Outline of cranium, dorsal view ; one-third natural size.

Fig. 3. A scute, about the natural size.