88 ON THE STRUCTURES AND DISTRIBUTION OF THE 



This family was first defined by the author in the Natural History Review, 1865. 

 The most nearly correct limitation previously existing was that of Giinther, who, 

 however, placed the species with parotoids in other families. 



EEMIPHRACTID^. 



Diapophyses of the sacral vertebra cylindrical ; mandible supporting a series of 

 teeth. Cranium fully osseous. Terminal phalanges ? 



Of this family almost nothing is known, as it is as yet represented by but two rare 

 species of the forests of the Neotropical region. It is probably intermediate between 

 the Hylidse and Cystignathidge ; in superficial appearance it approaches nearest the 

 genus Triprion m., where the cephalic ossification and developement of additional 

 teeth are carried far, and the digital dilatations are in like manner not largely 

 developed. , 



HEMIPHRACTUS. 



Wagler, Isis v. Oken, 1828, 735, 743, t. x. Peters, Monatsb. Preuss. Acad. 1862, 145. 

 In both species the vomerine teeth are in longitudinal series between the nares, 

 curved outwards, and there appears to be teeth on the palatine arch. They have an 

 acute prominence on the end of the muzzle, and the terminal tooth of the mandibular 

 series is several times as large as the others, and prominent. 



CYSTIGNATEID^. 



Vertebrae procoelian; no ribs; sacral diapophyses cylindrical, obtrihedral or 

 slightly depressed distally, inclined upwards. Coccyx separate, attached to two 

 condyles, without diapophyses. Terminal phalanges continuous, either uniformly 

 conic, or with divergent terminal processes or their rudiments. Manubrium wanting 

 or cartilaginous;* xiphisternum distinct. Auditory apparatus developed.! No 

 teeth on the mandible. 



This, after the Hylidse the most extensive family of the Arcifera, embraces 101 

 species, which represent thirty-four generic types ; four additional species represent 

 four other supposed genera. 



The most completely developed genus exhibits a cranium without fontanelle and 

 with complete ethmoid arch, and a styloid osseous xiphisternum, with terminal car- 

 tilaginous disc ; the auditory organs perfectly developed : the lowest, undeveloped 

 ethmoid arch and frontoparietal roof, and disciform cartilaginous xiphisternum with- 

 out style, with Eustachian tubes and membranum tympani wanting. Consistently 



* Except in Limnocharis. t Except in Alsodes, according to one author. 



