ON THE FAMILIES OF THE RANIFORM ANURA. 199 



HEMISUS. 



Giinther, Catal. Brit. Mus. 1858. Cacophrynvs Steindachner. 



This genus shows its nearest affines to be Callula and alhed genera of the Engysto- 

 midaj in the wide separation of the lobes of the liver for the accommodation of the 

 pericardial sac and its contents, and by the posterior position of the heart. In the 

 latter point it exceeds all other genera; the heart is of relatively large size, and 

 occupies nearly the median portion of the abdominal region. It would appear to be 

 for the protection of this important organ that the postcoracoids are extended back- 

 wards. The cavity anterior to the heart is occupied by longitudinal muscles and the 

 large larynx. The lobes of the liver extend each to the groin, a position even more 

 posterior than in those genera of Raniforcnia which are characterized by the posterior 

 position of that organ, and by the disappearance of its median lobe, and the wide 

 separation of its lateral lobes for the accommodation of the heart. The genera in 

 which this relation exists, as determined by numerous examinations, are Breviceps, 

 Engystoma, Systoma, Callula, Phrynomantis, Atelopus and Pipa. 



This genus exhibits also an external corpus adiposum, which I have not found in 

 Callula, Engystoma, or any other genus of Batrachia Each one is subtrihedral, the 

 apex resting near the extremity of the postcoracoid, the body lying between the 

 strata of the external and internal oblique muscles, along the anterior margin of the 

 lobe of the liver on each side. 



H. g u 1 1 a t u m Giinther, Catal. Engystoma guttatum Rapp, Erichson's Archiv. 1842, 

 290, tab. 



Habitat. Natal, (iVIus. Academy.) 



This species possesses the posterior cartilaginous cups observed by Steindachner on 

 the tongue of H. sudanense. They are probably insertions of the flabelliform 

 retractor muscle which withdraws the extremity of the tongue into the slit behind it. 

 The heart of this species is of unusual size. 



H. sudanense Steind., Verb. Bot. Zool. Gess. Wien. 1864, 284. H. gidneense 

 Cope, Nat. Hist. Review, Lond. 1865, (no description.) Cacophrynus sudauen&e 

 Steind., Sitzungsber. k. Acad. Wiss. Wien. vol. xlviii. 

 Habitat. Equatorial Africa. 



ARCIFERA. 



Supplementary to the preceding, some important characteristics of the structure of 

 the metacarpals and phalanges of certain Arciferous genera, e. g. Hylidie, may be 

 noticed. 



Tlie genus Hyla, as defined by the writer in " Genera of Arciferous Anura " 

 (Journal of the Academy, 186C), embraces a number of groups readily recognized by 



