APPENDIX TO THE CATALOGUE OF SHIELD REPTILES. 



21 



The species was originally named by Cuvicr from a spe- 

 cimen in the Paris Museum said to have been brought from 

 the Maequarie Itiver by MM. Lesson and Garnot ; 4 ind 

 the first four names quoted are derived from this specimen. 

 I am inclined to suppose that Mr. Gould's specimen, which 

 I described in Captain Gray's narrative, may be the same 

 species, as it is from the same river. 



2. Chelymys victoriae. 



Hydraspis victorias, G-rcnj, Zool. Misc. p. 55 ; P. Z. S. 1872, 



p. , t. (underside). 

 Chelymys macquaria and vox., Gray, Cat. Sh. Rcpt. p. 57; 



Suppl. Cat. tih. Kept. p. 76, fig. 25 (head) ; P. Z. S. 1856, 



p. 31, t. (and skull). 



Var. 1. Shell depressed, expanded. 



Var. 2. marmorata. Back more solid and convex, marbled. 



Var. 3. sulcata. Back with a central groove, shields ob- 

 scurely longitudinally grooved. 



Hab. N.W. coast of Australia, Victoria River (Capt. W. 

 Chambers, Mr. Gould) ; east coast of Queensland, Burnett 

 River (Mr. Krefft). 



This species appears to have a very extensive geogra- 

 phical distribution. There are several specimens in the 

 British Museum brought from the Victoria River by Capt. 

 William Chambers and Mr. Gould, and more lately several 

 specimens in spirit from Burnett River on the east coast of 

 Queensland. It is remarkable that the specimens received 

 at the same time from the Victoria and Burnett rivers 

 present such variation in form that one is induced to believe 

 that they are referable to two species. Having only one or 

 two specimens of the one from the Maequarie River, we 

 have not the means of deciding whether the same variations 

 occur in that river. 



The specimens agree in having a lead-coloured head, 

 with a broad streak from the middle of the hinder part of 

 the orbit to the upper front margin of the tympanum, and 

 a similar, rather broad, streak from the angle of the mouth 

 to the underside of the tympanum. In general the gullet 

 and throat below this line are white ; but in some they are 

 more or less varied with lead colour. The thorax in all the 

 specimens is much more oblong and convex than in the 

 specimens received from Segou, on the Maequarie River ; 

 but they vary both in the outline of the thorax and in the 

 convexity of the back very considerably. The smallest is 

 the broadest, with the back of the shell much elevated in 

 the centre. Indeed no two of the specimens are alike in 

 form and convexity, which induces me to believe that they 

 all belong to one variable species. 



** Thorax oblong, convex, high ; head large. 



3. Chelymys Krefftii. 



Thorax oblong, scarcely broader behind, very convex. 

 The second, third, and fourth vertebral shields as long as 

 or rather longer than broad ; the second and third nearly 

 square, with only a slight angle near the middle of each 

 side ; the fourth contracted behind ; the first nearly square, 

 rather broader than long, and rather broader in front. 

 Thorax convex, elevated from the margin, the lateral pro- 

 cesses convex. Head large, above olive, with a broad 

 white streak from the back of the orbit to the upper 

 front margin of the tympanum ; a broad white streak 

 from the angle of the mouth to the lower part of the 

 tympanum. Beaks very strong and convex. Upper part 

 of neck slightly granular. 



Chelymys Krefftii, Gray, Ann. fy Mag. Nat. Hist. 1871, viii. 

 p. 366 ; P. Z. S. 1872, p. , t. . 



Hab. Burnett River. 



One specimen (Krefft's MS. no. 9) is coloured very much 

 like the others received from Mr. Krefft, but differs in being 

 oblong and very convex, instead of being broadly ovate and 

 much more depressed, and in the form of the vertebral 

 plates. It also differs in having a much larger head com- 

 pared with the size of the body. 



It has been suggested that this may only be a difference of 

 sex ; but it is very curious that, out of a large series, it 

 should be the only one of the sex that has come to \is. 



EUCHELYMYS. 



Head covered with a continuous smooth skin, which is 

 reticulated over the temporal muscles, with an oblong, tri- 

 angular, diverging hard plate on each side of the occiput. 

 Chin with two beards. Back of the neck netted, slightly 

 tubercular or convex. Forehead and crown nearly square, 

 scarcely dilated behind ; hinder edge of occiput scarcely 

 sinuated. Thorax convex, solid ; cavity contracted in front ; 

 nuchal shields narrow, well developed ; vertebral shields 

 broad, the fifth as broad as or broader than the others. 

 Fore legs with large transverse scales in front and with 

 keeled scales on the outer margin. 



Euchelymys (part.), Gray, P. Z. S. 1872, p. 



I first established this genus in the ' Annals and Maga- 

 zine of Natural History' for August 1871, placing the two 

 species together, because they both had nuchal plates : but 



