Dr. A. GuMh^x on, the Tailless Batrachians. 



Q9 



\ Both the series of Opisthoglossa are not to be considered as form- 

 ing one continued series between the Aglossa and Proteroglossa ; 

 they do not form one series of animals, descending from the most 

 highly organized form^ to the lowest one : such a gradation is equally 

 found in both series ; and one is at once struck with the identity of 

 the chararacters in the single families, if brought side by side in two 

 parallel series. 



OPISTHOGLOSSA. 



Kanina. 



Bombinatorina. 

 Brachycephalina 



Bufonina. 



OXYDACTYLA. 



'' Ranidae. 



Cystignathida;. 



Discoglossidse. 



Asteroplirydidaj. 



Uperoliidae. 

 ^ Alytidae. 



Bombinatoridae. 



{Phryniscidae. 

 Brachycephalida;. 

 f Rhinoderraatidae. 

 J Engystomatidae. 

 1 Bufonidae. 



Platydactyla. 



Polypedatidae. 



Hylodidae. 



Hylidaj. 



Phyllomedusida;. 



Pelodryadidae. 



Micrhylidae. 



Hylaedactylidae. 

 Brachymeridae. 



Hylina. 



Micrhylina. 



Hylaplesina. 



Hylaplesidae. 



I am always afraid of admitting teleological principles into natural 

 science ; the most important results of truth are gained by adhering 

 to objective facts, and by inquiring into them. Each system should 

 be adapted only to the present state of our know^ledge of animals ; but 

 at last we must come to that point where analogies will enable us to 

 look further ; and the future will show (if it is allowed to presume 

 so far) that, among the forms which hereafter may be discovered, 

 there will be found correspondents to the Asterophrydidce, Phry- 

 niscidce, Brachycephalidcp, BufonidcGy and Hylaplesidce, viz. : — 



1 . Hylina^ without paratoids, with dilated sacral vertebra and free 



toes. 



2. O. 'platydactyla y without maxillary teeth and with imperfectly 



developed ear. 



3. Hylaplesina, with paratoids, with dilated sacral vertebra, and 



webbed toes. 



4. Bufonina, without paratoids, with not dilated sacral vertebra 



and free toes. 



Only three genera are known belonging to the first group of 

 Anura, to the Aglossa, — Bactylethra, Pipa and Myobatrachus, the 

 latter of which is imperfectly known to myself from a short notice of 

 Dr. Gray in the * Proc. Zool. Soc' All these three genera offer such 

 characters as to become the types of as many families. But as I do not 

 know whether the star-like configuration of the toes in Pipa, or the 

 horny claws of the toes of Bactylethra, have the same functional im- 

 portance as in the Oxydactyla and Platydactyla, or whether the 

 two horizontal fangs in the intermaxillary bone of Myobratrachus are 

 true teeth, or only apophyses (as in the lower jaw of Tomopterna), 

 I am at a loss which of these characters must be subordinated to the 



