1891.] TADPOLES OF THE EUROPEAN BATRACHIANS. 601 



IV. PELOBATID^. 



4. Pelobates, Wagl., 1830. 



12. fuscus, Laur., 1/68. 



13. cultripes, Cuv., 1829. 



5. Pelodytes, Fitz., 1838. 



14. punctatus, Daud., 1802. 



V. DISCOGLOSSID^. 



6. DiscoGLOssus, Otth, 1837. 



15. pictus, Otth, 1837. 



7. BoMBiNATOR, Merr., 1820. 



16. igneus, Laur., 1768. 



17. pachypus, Fitz., 1838. 



8. Alytes, Wag]., 1830. 



18. obstetricans, Laur., 1768. 



19. cisternasii, Bosca, 1879. 



It is with no small satisfaction that I look over this list and com- 

 pare it with that drawn up by Schreiber (' Herpetologia Europsea ') 

 in 1875, in which only 12 species are enumerated, as showing how 

 much progress has been made within the last fifteen years. Through 

 the researches of Fatio, Lataste, Leydig, Heron Royer, Camerano, 

 Piiiiger, Born, Bedriaga, and myself, the right to specific rank of the 

 forms allied to Rana temporaria that had been distinguished by 

 Nilsson, Steenstrup, and Thomas has been indisputably established ; 

 the question of the distinctness of the two species of Bomhinator 

 has been settled ; and four altogether new species have been added. 



Key to the Identification of Genera and Species of European 



Tadpoles. 



I. Spiraculum sinistral ; labial teeth disposed in a single 

 row in each series or ridge, 



A. Anus dextral ; spiraculum directed backwards and 

 upwards ; lower lip bordered with papillse. 

 1. Anus opening close to the lower edge of the tail ; 

 upper caudal crest not extending forwards be- 

 yond the vertical of the spiraculum ; eyes on the 

 upper surface., I. Rana. 



a. Series of labial teeth — ^ — . 



Interocular space at least twice the distance between the 

 nostrils, and much greater than the width of the 

 mouth ; tail acutely pointed, at least nearly twice as 

 long as the body 1. B. escwlenta. 



Interocular space but little wider than the distance be- 

 tween the nostrils or the width of the mouth ; tail 

 once and two thirds to twice as long as the body 2. B. arvalis. 



b. Series of labial teeth — ■ — . 



4 



a. Tail obtusely pointed, once and a half to 

 twice as long as the body. 

 Second series of upper labial teeth widely interrupted in 



