i'G 



APPENDIX TO THE CATALOGUE OF SHIELD REPTILES. 



the nose, one on either Bide behind the eye, one on either 

 the margin of the frontal plate, bul without a. 

 liurk spot in its middle, b larger one on either aide at the 

 margin of the parietal plate close over the tympanum, and 

 ■jii,' below behind each lower-jaw branch. These spots arc 

 rnible in quite young animals. 



"•Foundl nion in Uupununi andTakutu. Their 



way of living agrees perfectly with that of PeltocepJuihu 

 Traeoya ; they belong also to the edible Tortoises of Guiana. 

 Long. 10 1- inches.' 



••Mr. Solater, in his list of accessions, Froe.Zool.Soc. 1871, 



• rvea : ' a small Tortoise of the genus Podocnemis 



from the Upper Amazons, purchased December 16th, and 



certainly referable to P. uni/Msot Troschel ( Schomb. Guian. 



iii. p. 647). Mr. Edward Bartlett, who has met with this 



ies in the same district, informs mo that his specimens 



of it in the British Museum have been referred to the 



young of P. Dumeriliana. This, I think, can hardly be cor- 



l'.ut I shall have some further remarks to make on 



this subject in some notes, which I have in preparation, on 



the Tortoises living in the Society's Gardens.' 



••The place where Podocnemis 101 (/(7/s was described had 

 . so that I did not refer to it in my ' Supplement 

 to the Catalogue of Shield Reptiles.' It is very true that 

 there is a specimen in the Museum, purchased of Mr. Iiart- 

 lett, which agrees with the description of P. unifilis above 

 quoted, and which I have considered a young specimen of 

 icnemis Dumeriliana, as it agrees with the other young 

 specimens in the Museum in every particular. These young 

 - imens have already been described as distinct species 

 under the names of Emys cayanensis, Sehweigger, E.erythro- 

 . ephala, Spix, and also as Hydrastis lata, Bell, from a 

 specimen formerly in the Zoological Gardens. 



•• The character which M. Troschel seems to depend on 

 as distinctive of his species, from the manner in which he 

 underlines the words and the name which he gives to it, viz. 

 P. 'iiijilis (that is, from having only one beard in front of 

 the chiui. is. I believe, common to all the species of the 

 family Peltocephalidce ; at least it exists in all the Museum 

 specimens (except one small specimen of P. expanses) of 

 Chthnemys Dumeriliana, Podocnemis expansa, and Bart- 

 lettia pitipii ; and Cornalia mentions it as one. of the cha- 

 racters of his Podocnemis 6-tuberculata, which is unknown 

 to me. The single exception mentioned is in all respects 

 like the other specimens ; the two beards arc quite close 

 together in the front of the chin, as if it were one beard slit 

 down the centre, and not far apart as in all two-bearded 

 Tortoises. The spots on the head are only found in young 

 specimens, and disappear as the animal increases in age ; 



therefore I think we may decide that Podocnemis unifilis 



is a synonym of /'. Dumeriliana in the young state. And 

 it is curious that so accurate an observer as Troschel 

 should have overlooked this fact when he considered it a 

 nrw species; bul very likely he had no species of the family 



nt his command. 1 1 is less excusable in M r. Sclater to make 

 the observation he has done, who is, by his own account, 

 new to the study of Tortoises (see P. Z. S. 1870, p. 667), 

 bul who could have examined the extensive series of 

 these animals in the .Museum. 



" Sir Charles Schomburgk observes that 'the flesh of the 

 Tortoises of this family is fat and the most savoury of any 

 of the Freshwater Tortoises.' " — Ann. $ Mag. Nat. Ilist. 

 1871, viii. pp. GS-70. 



3. PODOCNEMIS. 



Head short and broad; alveolar surface of upper jaw flat, 

 with three diverging ridges, separated by a flat rugose space 

 in the middle, the inner one low and distinct ; lower jaw 

 with a sharp outer edge, a deep longitudinal concavity, the 

 inner margin elevated, divided by a central longitudinal 

 groove into two ridges ; the central notch not produced for- 

 ward. (Gray, Cat. Sh. Rept. tab. 37. f. 1.) Tympanum 

 large. 



The young animal is black, the head ornamented with 

 large white spots. 



Podocnemis, Gray, P. Z. S. 1870, p. 719. 



Podocnemis expansa. 



Gray, Suppl. Cat. Sh. Sept. p. 83; P.Z.S. 1870, 



p. 720 ; P. Z. S. 1871, p. 747, f. 1 (tympanum). 

 Wagl. Schomb. Reise in Brit. Guiana, iii. p. 647. 



" The largest of the noticed British-Guiana freshwater 

 Tortoises, we met with most commonly in Takutu and Rio 

 Banco, although it (judging from the number of eggs 

 which we found on the sand banks of the Essequibo) must 

 be tolerably common in this place. It belongs without 

 doubt to one of the fattest and most savoury of the freshwater 

 Tortoises. It has found excellent describers in Humboldt 

 and Spix." — Schomburgh. 



BARTLETTIA. 



Head short and broad ; alveolar snrface of the upper jaw 

 flat in front, shelving and concave behind, with a very in- 

 distinct, short, subcentral ridge parallel to the outer margin : 

 alveolar surface of the lower jaw with a slightly raised 

 ridge on the outer edge, narrow, slightly concave in front. 



