114 S. IITROTA. 



broadened towards the right side. On the other hand the spinal cord 

 at this region shows a slight local thinning (compare figs. 4 and ;5), and 

 the space between it and the right wall of the vertebral canal is filled 

 with exuberated elements of the pia mater with uimsually swollen blood- 

 vessels. 



The above abnormality of the caudal vertebra is, in all appearances, 

 a mark left by a previous injury, probably a cleft that entered the tail 

 from its right side and affected the vertebral column, without however 

 extending so far as to injure the spinal cord. Now remembering that 

 the accessory tail arises at exactly the position where that partial injury 

 took place, the assumption that the latter was the cause of the forma- 

 tion of the former, lies close at hand. 



So then, it seems to be warranted to assume the present individual 

 oi AblepharNs Bouf onii,h.a,dsu.stS:med two injiu'ies to the tail; a total, 

 that led to the regeneration of the main tail and a partial, that led to the 

 generation of the superfluous appendage which I have called the acces- 

 sory tail. Whicli of the two injuries is the older, or whether both 

 occurred simultaneously, is a dithciilt question to decides. If, however, 

 the darker or lighter shade of the external colouring of reproduced scales 

 can be regarded as indicative of their relative age as I believe it can be to 

 a certain extent, I should say that the regenerated part of the main tail 

 and the accessory tail are likely of about the same age, since the 

 two agree in the above respect. The small size of the one as compared 

 with the other is at any rate sufficiently intelligible from the important 

 negative points in its internal structure. 



In conclusion, I wish to tender my warmest thanks to Prof. Dr. 

 Ijima, who has kindly gone over my preparations and endeavored to 

 bring my manuscript to a presentable form. 



EXPLANATIONS OF PLATE XV. 



Fio-. 1. Ontline of Ablc])]iitni'^ Jjoittonil with accessory tn.\]. Dorsal view. Xatural 



size. 

 Fi<?. 2. Accessory tail and adj icent paris of the main tail. Ventral view. 4 tiin(\s. 

 l''io-. ?i. Ventral view of the main tail, maiynfit'd -1. times, corresponding- to tl^e 



stretcl} bet'(yeen n and '' in fi"". 1. 



