DISCOGLOSSUS. 129 



muuicate by any openings with the floor of the mouth. 

 Horny blackish excrescences are largely developed 

 and distributed as isolated minute spines over the 

 ventral surfaces and on the hind limbs ; t]jiey form 

 large groups on the inner palmar tubercle and the two 

 inner fingers, a band round the chin, and often border 

 the web of the foot. These excrescences usually 

 persist longer than in most other Batrachians, being 

 found, more or less developed, in adult specimens all 

 the year round. 



Geographical Variations. — The polymorphism of 

 this species has given rise to the establishment of 

 various species and sub-species, which were believed 

 to be restricted to certain parts of the habitat of the 

 genus. Thus a Discoglossus sardus, Tschudi, was 

 stated to be peculiar to Sardinia and Corsica, and a 

 D. scovazzii, Camerano, was described from Morocco. 



Lataste, in his monograph of 1879, had, it seemed, 

 disposed once for all of these supposed species by 

 showing the inconstancy of the characters adduced 

 for their separation ; and, for my part, after examin- 

 ing a very large material from almost every part of 

 the habitat, I fully agree with him. But, since 

 1879, the 1). sardus has been maintained, no longer 

 as a species, but as a sub-species, by Camerano, 

 and the D. scovazzii, or a form very closely agree- 

 ing with it, has been revived by Heron-Royer under 

 the name of D. auritus ; it may therefore be well 

 to explain in a few words why I take no notice of 

 them even as varieties. According to Camerano' s 

 latest definition, D. sardus, from Sardinia, Corsica, 

 and neighbouring small islands, differs from the 

 typical D. pictus from Sicily, Malta, and the Spanish 

 Peninsula in having a less acuminate snout, more 

 robust limbs, and the length of the tibia contained 

 twice, or a little over twice, in the length of head and 

 body. The two former characters are really too slight 

 to be easily appreciable ; and besides, I find Maltese, 

 Algerian, and Portuguese specimens with the snout 



I 



