142 Mr. G. A. Boulenger on the 



but the tympanum, although as distinct, is not so large. 

 Specimens from Shanghai, Chef'oo, Peking, and Corea are 

 intermediate between the latter and the European ; the tym- 

 panum is always very distinct, but varies considerably in 

 size ; the dark lateral stripe is usually ill-defined or absent, 

 and the belly may be either largely spotted with black or 

 almost immaculate. Judging from the two specimens col- 

 lected at Chabarowka by Hr. Domes, the northernmost form 

 is still nearer the European ; the tympanum is rather small, 

 but perfectly distinct, the belly is immaculate, and the colora- 

 tion might be said to be identical with that of European 

 specimens, but for the presence of traces of a light vertebral 

 line, as is often found in specimens from Japan, Corea, and 

 Northern China. The following table shows (in millims.) the 

 variations in the size of the tympanum : — 



P t-s O O 



cJ 



From snout to vent 76 



Diameter of the eye .... 

 Diameter of the tympanum 



17. Ilyla Stephen!. 



Bouleng. P. Z. S. 1887, p. 579, pi. li. fig. 1. 



Of this species, recently described from a specimen received 

 alive from Port Hamilton, Corea, by the Zoological Society, 

 two specimens, male and female, from the Ussuri River, are 

 in Hr. Dorries's collection. It is easily distinguished from 

 H. arbor ea by the much larger and more prominent metatarsal 

 tubercle. 1 give the following measurements of the two 

 specimens : — 



6 : $• 



millim. millim. 



From snout to vent 35 40 



Length of head 12 13 



Width of head 13 15 



Diameter of the tympanum 2 3 



Fore limb '. 20 23 



Hind limb 51 57 



Tibia 15 17 



Inner toe 4 4 



Inner metatarsal tubercle 2 5 25 



