90 ON THE STRUCTURES AND DISTRIBUTION OF THE 



trum,* Crinia, BorborocEetes, Eusophus and Hyperolia, and in none can I find more 

 than lateral traces of the epicoracoid and coracoid septa, except in the Hyperolia 

 marinorata, where they are complete. The posterior abdominal is well developed 

 in Eusophus n e b u 1 o s u s. 



Pleurodem^. — Ventrolateral low down, and posterior abdominal well developed in 

 Pleurodema b i b r o n i i. 



Hylodes. — Dorsolateral and ventrolateral far apart : the transverse posterior ab- 

 dominal septum in the species of Lithodytes, in Ephirexis 1 o n g i p e s, in Enhydro- 

 bius vom e ri n us (^/osra Girard) and Phyllobates ridens. I have not found it 

 in Lithodytes (Craugastor) conspicillatus Gthr., Enhydrobius parvusf 

 {Hylodes Gird.) and Limnocharis f u s c u s Bell [Eloda nasus Girard). 



Cystignathi. — In all the species the structure is similar to that of Rana, except in 

 the approximation of the dorsolateral lines, and the presence of the postabdominal 

 septum, which is continuous with the lateroventrals, and is indicated externally in 

 several of the species by a fold in its line of attachment. 



The accompanying table exhibits the affinities of the genera, and the groups into 

 which they naturally fall : 



*P. occidental e, sp. nov. 



Skin smooth ; crural g'land small ; above medially dark, laterally pale ash, below dirty white ; pupil erect ; 

 orbit less than length of muzzle. 



Habit stout ; distal end of tarsus not quite extending to end of muzzle ; breadth of head behind scarcely less 

 than one-half length of head and body, and one-eighth more than from posterior border of tympanum to oppo- 

 site end of muzzle. Muzzle depressed in profile, retreating from prominent labial border, nostril nearer orbit 

 than margin, the former distance equal narrowest interorbital breadth. Eyes not prominent ; eyelids narrow. 

 Vomerine series extending to exterior of choans, which, with the ostia tubse Eustachii, are of usual size. 

 Tongue extensively free. Tympanum concealed by skin. First, second and fourth fingers equal, the two inner 

 with very large penultimate subarticular tubercles. Brachium attached under angle of mouth ; middle of ante- 

 brachium extended measures end of muzzle. Tarsus broad, short, scarcely equal antebrachium ; metatarsus 

 moderate, with none but the cuneiform tubercle, which is incurved and pale edged. Toes short, except the 

 fourth, with a trace of web, and margined. 



Total length 1 in. 94 1. ; muzzle to angle of jaws 8'5 1. ; tibia 9 1. ; foot 1 in. 2'1 1. 



Habitat. — West Australia, Darnel. 



t Perhaps owing to small size of specimen. 



