SOMi: SOUTH INDIAN BATRACHIANS. 121 



i?. temporaria, and Dr, Annandale(gr) states that he has been able to confirm 

 the observations of Dr. Nicholls on most of the bones by an independent 

 examination. In South Indian colleges where practical zoology is 

 taught, the laboratory type is B. hexadactyla, and during the breeding 

 season of frogs, examples of B. tigrina are frequently brought to the 

 class for practical work. The skeleton of a B. tigrina S. S. prepared for 

 the Central College recently showed certain abnormal indi%ddual vari- 

 ations and led to the making of a large series of skeletons of this species 

 for the purpose of comparison. On a careful examination of these series 

 with the skeletons of B. hexadactyla and B. cyanophlyctis, I am not able 

 to confirm some at any rate of the statements of Dr. Nicholls. 



(a). The vertebral column : — In regard to the neural arches, B. tigrina 

 is said to show, '' a very marked overlap of each arch dorsally upon that 

 immediately posterior to it and accordingly when the vertebrje are in 

 position, the centra are not visible from above (/i)". " In this imbricate 

 condition of the vertebral column, it would appear then, that B. tigrina has 

 retained (or reverted to) a somewhat primitive condition (i)" such as is met 

 with in the families of Discoglossidce and Pelohatidoe. The condition, 

 shown in text fig. 1 of the paper cited,in support of the above statement, is 

 easily produced by a bend or flexture such as appears in badly prepared 

 skeletons, (j) and ; however, in carefully prepared bones the neural arches 

 only notch between the zygapophyses (h) so as to produce a more or less 

 open-work condition that Dr. Boulenger ( Z ) describes as being character- 

 istic of the genus Bana. I possess two skeletons of B. esculenta and a 

 comparison with them or with the two other Indian species already 

 mentioned, discloses nothing strikingly different in the vertebral 

 column of tigrina. I may further mention that its vertebral column 

 is certainly not like that of Discaglossus pictus (m) and the figure 

 of Dr. Nicholls therefore does not represent the correct position of 

 the neural arches in well prepared and normally articulated spinal column. 

 It is further pointed out that the imbricate condition of the neural arches 

 is produced in trigina as in Pelobates fuscus, by the fact that in these 

 examples the centrum has practically the same length as the neural 

 arch (to). In the vertebrae of B. tigrina that I have forwarded to Dr. 

 Annandale, the length of the centrum is 1^ of the length of the neural 

 arch measured along the mediam line. This holds not only for the 

 sixth vertebra that Dr. Nicholls selects for comparison, but for all others in 

 the series. The dorsal view of the vertebral column of B. tigrina is not, 

 however, the fully and completely open-work condition figured for B. tem- 

 poraria by Howes (o) and for B. esculenta by Ecker, (p) and the seemingly 

 imbricate appearance is due to, — I. The largely developed neural spines, 

 directed backwards hiding the vertebral gaps. 2. The pre and post 

 zygapophyses are considerably flattened and hide the communications 

 between the dorsal gaps and the vertebral foraminae, and 3. On the 

 posterior border of the neural arch of some of the vertebrss, a flange or 

 arcualium is developed. ^ 



(g) 1917, Mem. As. Soc, Bengal, Vol. VI, p. 124. 



(h) 1915, Proc. Zool. Soc, p. 603. 



(i) 1915, ibid. pp. 603-604. 



(/) All osteological material in support of these statements are sent to the 



Indian Museum, 

 {h) This is true of E. hexadactyla and E. cyannophlyctis also. 

 (I) 1897, the Tailless Batrachians of Europe, Vol. I. p. 38. 

 im) 1907, Wiedersheim and Parker Comp. Anat. Vert., p. 56. ' 

 in) 1915, Proc. Zool. Soc, London., p. 605. 

 (0) 1902, Howes, Atlas Pract. EI. Zool, pi. IV., fig XXXV. 

 (p) 1889, Ecker. Anat. Frog., p. 18( 

 16 



