36 
Annals or the Transvaal Museum. 
Pyxicephalus (R. adspersa , delaiandi , natalensis , etc.,) and it is a note- 
worthy fact that this section (as understood by Nieden) is confined to 
tropical and South Africa, w th an odd spscies in Madagascar, 
from which we may conclude that Pyxicephalus really is endemic in this 
region. Although in some of its characters it is no doubt very specialized, 
yet on the whole I think Pyxicephalus is more primitive than the ordinary 
type of Pana : for instance, whereas in Pana the metatarsals are separated 
by web. this is not the case in Pyxicephalus, the condition in Pana being- 
no doubt a secondary adaptation character. There is therefore some 
justification for the supposition that the genus Pana arose on the African 
continent. Fossil Pan dae are recorded from the Eocene of India 
(Oxylossus) and from the lower Miocsne of Germany (Pana). 
The sub-family Dendrobatinae (Dendrobatidae of some authors) has 
two genera in Madagascar, Nossi Be and Peunion, one in French Congo, 
and one in South America. They appear to differ from Raninae only in the 
absence of teeth, and Gadow therefore questions if they really constitute a 
natural group. In the absence of certain evidence on this point we 
cannot make use of their distribution data : it is important to note, 
however, that parallel facts of distribution are known in other groups of 
vertebrates. 
E ng ystomatidae . 
The most typical section of this family is the sub-family Engysto- 
matinae. The South African genera Hemisus and Breviceps are con- 
fined to tropical and South Africa whilst the third genus, Phrynomantis, 
has also a representative in the island of Amboina. It is worthy of note 
that in Africa this genus properly belongs to the tropical region, ranging 
from Gold Coast and Angola to German East Africa, and extending south- 
wards into the sub-tropical portions of our area, but not reaching Cape 
Province (Phrynomantis occurs at Kimberley, but Miss Wilman believes 
that it is an accidental introduction along with mine timber.) Madagascar 
has four genera, of which three are peculiar, whilst the fourth. Calophrynus, 
has other species in Borneo, Burmah, and South China. The whole sub- 
family is distributed as follows : Tropical and South America, seven 
genera ; Africa three ; Madagascar four ; India and Malay region, especially 
New Guinea, thirteen. The inter-relationships of these various genera are 
unknown to me. The sub-family Dyscophinae includes about ten 
genera, which are all confined to Madagascar, with the exception 
of Calluella in Burmah, Colpoglossus in Borneo, and Cacosternum in 
Africa. The genus Cacosternum differs, however, from all other 
Dyscophinae except Anodontohyia in the absence of palatine teeth, 
and as the precoracoids also are absent, it must be counted as a 
degenerate member of the sub-family and a connecting link with the 
Engystomatinae. As this sub-family constitutes the more primitive 
section of the Engystomatidae, we may surmise that the original home 
of the family was in the Indo- Oceanic region, an assumption which is in 
agreement with the present-day distribution of the Engystomatinae : 
and seeing that these genera as a whole are slow of movement, their more 
extended distribution in South America would seem to indicate that the 
Engystomatinae are not so recent as the Paninae. 
