DEVELOPMENT OF THE SKULL IN THE BATRACHIA. 
155 
Fifth genus. Rappia. 
41. Rappia -? sp.—Adult female ; f- inch long. Lagos. 
This specimen was collected, with others, several years ago at Porto Novo, near 
Lagos, by ft. B. Walker, Esq., and was sent to me by Mr. T. J. Moore, of Liverpool, 
on March 24, 1874. 
Dr. Gunther was doubtful of the species, although there is a Rappia lagocnsis 
(see Gunther, P. Z. S., June 25, 1868, pp. 478-490 ; a figure of that species is given 
in plate 40, fig. 2, and a description at p. 487). 
Dr. Gunther gives the length of P. lagoensis as 28 millims. ; my specimen measured 
only 21 millims., although a female. In the paper just referred to, 15 species of this 
genus are given—all African. In the “Batrachia Salientia,” p. 85, these are described 
under the generic term Hyperolius, a name now used instead of Uperoleia (ibich, p. 39) 
for a genus related to Alytes. The only Australian kind described in that work is 
TI. bicolor (p. 89) from Port Essington. The author remarks of this, whose skull I 
shall describe next, that—This species is very probably the type of a separate genus.” 
This suggestion is a true one; the Australian type has an exceedingly different skull 
from that which I shall now describe from West Africa. 
This skull (Plate 28, figs. 6, 7) greatly resembles the last but one (figs. 1, 2) ; and the 
thought that occurs is this—Are the African Rappice dwarfed “races” of various 
species of the “ Polypedatidsetypes which attain so large a size in the Oriental region ? 
This is a rather long skull; the length and width are equal, and it tends towards 
the triangular form. The condyles of the quadrate ( q.c .) do not reach so far back as 
in the last but one, they end in front of the fenestrce ovales. 
The occipital condyles ( oc.c .) are similar—they are large and posterior; but the 
basal emargination is less in this species. In conformity with the greater breadth 
across the ears, the simply oval form of the capsules is lost, and there is a considerable 
tegmen tympani (fig. 6). The general form of the mid and fore skull is very 
much alike in both kinds, but they are both a little broader (relatively as well as 
really) in this small adult; and the nasal roofs are like those of a metamorphosing 
Rana temporaria (see Phil Trans., 1871, Plate 8, fig. 1). The four bony tracts of 
the hind skull ( pr.o ., e.o.) are like those of the same of Young Frogs; whilst the 
girdle-boue is like that of quite old individuals, and the skull, altogether, is a curious 
mixture of old and young characters. 
The notochord (figs. 6, 7, nc.) is persistent; there is, as in the last but one, only one 
large fontanelle, the tegmen cranii being very short in front, short behind, and not 
present along the sides in most of the orbital region. 
Below (fig. 7), the prootics and ex-occipitals slightly overlap the wings of the 
parasphenoid ( pa.s .); but the cruciform synchondrosis is very large. Below, the 
ex-occipitals reach half way between the vagus-passage (X.) and the stapes (st.) ; 
K 2 
