602 MR. G. A. BOULENGER ON THE [NoV. 17, 



the middle ; first series of- lower labial teeth at least 

 two thirds the length of the second; width of mouth 

 a little less than the interocular width, which equals 

 about once and a half the distance between the 



nostrils 3. B. temporaria. 



Second series of upper labial teeth continuous or nar- 

 rowly interrupted ; first series of lower labial teeth 

 at least two thirds the length of the second ; width of 

 mouth quite as great as the interocular space, which 

 equals about once and a half the distance between 



the nostrils 4. R. grcBca. 



Second series of upper labial teeth widely interrupted in 

 the middle ; first series of lower labial teeth hardly 

 half as long as the second ; width of mouth much less 

 than the interocular space, which equals nearly twice 

 the distance between the nostrils 5. B. iberica. 



j5. Tail acutely pointed or submucronate, at least 

 nearly twice as long as the body. 

 Intei'ocular space once and a half the width of the mouth 

 or the distance between the nostrils ; no tubercle on 



the upper mandible 6. R. latastii. 



Interocular space at least twice the width of the mouth or 

 the distance between the nostrils; usually a black 



tubercle on the upper mandible 7. B. agil/is, 



2. Anus opening above the lower edge of the tail ; 



upper caudal crest extending far forwards on 



the back, almost to between the eyes, which are 



lateral and visible from the ventral as well as 



from the dorsal aspect of the body ; series of 



o 



labial teeth " II. Hyla. 



8. H. arborea. 

 B. Anus median. 



1. Spiraculum directed straight backwards ; tail 



rounded at the end ; both upper and lower lip 



o 



with toothed edge ; series of labial teeth - III. Bufo. 



Mouth at least as wide as the interocular space, which is 

 twice as great as the distance between the nostrils ; 

 second upper series of labial teeth very narrowly in- 

 terrupted in the middle 9. B. vulgaris. 



Mouth nearly as wide as the interocular space, which 

 measures once and a half the distance between the 

 nostrils ; second upper series of labial teeth more or 

 less interrupted in the middle 10. B. viridis. 



Mouth considerably narrower than the interocular space, 

 which is nearly twice as great as the distance between 

 the nostrils ; second upper series of labial teeth very 

 widely interrupted in the middle 11. B. calamita. 



2. Spiracxolum directed upwards and backwards; 



lower lip bordered with papilla ; series of labial 

 teeth -- or -. 



4 5 



a. Tail acutely pointed, without black lines ; first 

 series of upper labial teeth short ; beak entirely 



black ly. Pelobates. 



Tail once and a half to twice as long as the body ; inter- 

 ocular space at least twice, often nearly thrice, the 

 distance between the nostrils, and considerably greater 



than the width of the mouth 12. P.fusms. 



Tail hardly once and a half the length of the body ; inter- 



