90 HERPETOLOGICAL NOTES. 



sometimes almost separates the narrow gulars, but the 

 elongate form and the size of the first vertebral shield of 

 the latter enable us to easily distinguish the two forms. 

 In the genus Emydura the intergular always separates 

 the gulars, but in that genus the humerals meet behind 

 it and form an extensive suture. The first vextebral too, 

 is not broader than the second. I have no hesitation, 

 however, in placing such a globose form in the genus Chelo- 

 dina. The kej^ here given serves to show the relationships 

 of the seven species. 



Key to the species of the genus Chelodina : — 



A. Intergular more than twice as long as the suture between the 

 pectorals. 



B. Front lobe of plastron much narrower than the carapace. 

 Suture between the anals twice as long as that 

 between the pectorals and humerals, which 

 are equal. C. noi'ce-guineoe, Blgr. 



Suture between anals a little longer than that 

 between the femorals, but much longer than 

 that of the pectorals. 



C. steindachneri, Sbnrk.* 



B.B. Front lobe of plastron neaily as wide as the front lobe of 

 carapace. C. longicollis, Shaw. 



A.A. Intergular not twice as long as the suture between pectorals. 



C First vertebral shield markedly broader than second, 

 ftulars in contact. 



d. Plastron (without bridge) twice as long or less 

 than twice as long as broad. 



Second and third vertebrals longer than 

 broad. C. expansa. Gray. 



Second and third vertebrals broader than 

 long. C. siebenrocki, Werner. 



dd. Plastron more than twice as long as broad. 

 Second and third vertebrals considerably longer 

 than broad. C. ohlonga. Gray. 



C.C. First vertebral shield as long as and as broad as 

 second. Gulars separated by the intergular. 



C. i flier gular is. Fry. 



* Siebeniock : — K. Ak. Wiss. Wien (Math-naturw.) Anz. No. xviii. 

 1914, p. 1. 



