276 Reviews — Prof. Credner — On BrancM&saunis, 



1. — Peofbssok Dr. Hermann Credner on the Development 



OF Branchiosaurus.^ 



IN this valuable communication to Paleeontological science Prof. 

 Credner gives us the result of his observations on the life- 

 history of a single species of Labyrinthodont, or Stegocephalian^ 

 based on the study of no less than 76 specimens. 



The paper commences with a discussion of nomenclature and 

 synonymy ; but here we regret to say that we cannot quite agree 

 with the author's conclusions. Prof. Credner states that in 1881 

 he described the skeleton of a small Labyriathodont from the 

 ' Rothliegendes ' of Saxony under the name of Branchiosaurus- 

 gracilis, while on a subsequent page of the same memoir he described 

 a second specimen as B. amblystomus. Subsequent ' finds ' showed 

 that the former is but the larval condition of the latter, and Prof. 

 Credner proposes to adopt the name B. amblystomus for the species. 

 He proceeds, however, to mention that Messrs, Geinitz and Deich- 

 miiller have pointed out that B. gracilis is probably identical with 

 Protriton petrolei of Gaudry, from the Permian of France and 

 Thuringia, and he therefore concludes that the latter is also a larval 

 form, of which the adult may be perhaps still unknown, or may be 

 the so-called B. amblystomus. So far no objection can be taken to 

 Prof. Credner's views ; but when he proceeds to observe that the 

 name Protriton petrolei, as being founded on a larval form, ought to 

 be withdrawn, we cannot agree with him. There appears, indeed, 

 to be no doubt that Messrs. Geinitz and Deichmiiller are right in 

 regarding Branchiosaurus and Protriton as generically the same, and 

 there is also a very strong presumption that B. gracilis {B. ambly- 

 stomus) and P. petrolei are also specifically identical. Now the 

 generic name Protriton was first published (with figures of the 

 type specimen) by Gaudry in the " Bull. Soc. Geol. France," ser. 3, 

 vol. iii. p. 300 (March 29, 1875) ; the type specimen having been 

 previously recorded under the name of Salamandrella petrolei in 

 the " Comptes Eendus," vol. Ixxx. p. 442 (Feb. 15th, 1875), the 

 earlier generic name being withdrawn on account of being pre- 

 occupied. The term Branchiosaurus was first published by Fritsch 

 in the " Sitz. k. bohm. Ges. Wiss." (19th March, 1875),^ p. 72; 

 but was not figured till 1879, in the "Fauna der Gaskohle," etc., 

 pt. 1, p. 69, pi. i.-iv. The generic name Protriton is therefore, 

 strictly speaking (if we count from the date of the reading of the 

 memoir), of ten days' later date than Branchiosaurus ; but since 

 the date of figuring gives no less than four years' advantage on the- 

 side of the former, we think that the generic name Protriton ought 



^ "Die Stegocephalen aus dem Kothliegenden des Plauen'schen Grundes bei 

 Dresden," VI. Theil. — Zeitschr. deutsch. Geol. Ges. pp. 576-633, pis. xvi.-xix. 

 (1886). 



^ Fritscli (Fauna der Gaskohle, etc., pt. i. p. 69 [1879]) totally ignores Ms- 

 previous preliminary notice of the genus, and expressly states that it should date- 

 only from the time of figuring (1879). 



