DEVELOPMENT OF THE SKULL IN THE BATEACHIA. 
625 
a. The “ orbitar process ” in the Tadpole forms a perfect arch over the temporal 
muscle. 
b. The second upper labial coalesces in the adult with the internasal plate in front, 
and with the antorbital bar behind. 
c. The palatine cartilage is segmented off both from the ethmoidal (palato-trabecular) 
and also from the pterygoid. 
d. The upper part of the mandibular pier can be traced in the adult above the 
“ condyle of the pedicle ; ” the stylo-hyal coalesces both with it and with the ear-sac. 
e. There is no separate metapterygoid bone. 
f. The columella does not subdivide its cartilaginous core ; the subdivision here takes 
place far forwards, and not near the stapes, and is segmented, merely, as in Osseous 
Fishes, by separate bony shafts. 
g. The extrastapedial is a large semioval leaf, and the suprastapedial coalesces with 
the “ tegmen.” 
h. The hyoid bar coalesces with the periotic capsule. 
i. The cartilaginous “ annulus tympanus ” forms only two thirds of a circle. 
j. The common aliethmoidal, aliseptal, and alinasal roof is only one fourth the size. 
k. The prorhinals or cornua trabecula are much smaller. 
On the Skull of the Clawed Cape Toad (Dactylethra capensis, Cuvier). — First Stage. 
For the skulls of the adult of this aglossal Toad I am indebted to Professor Huxley 
and Dr. Dobson, of Netley ; for the larval forms, in their various states, to Mr. T. J. 
Moore, of Liverpool. 
The young of this type was supposed by the late Dr. J. E. Gray, F.R.S., to be a distinct 
species, and it was called by him Silurana tropic alls (Ann. & Mag. Nat. Hist. ser. 3, 
vol. xiv. p. 316, and Proc. Zool. Soc. Nov. 8, 1864, pp. 458-464). I have the satisfaction 
to find that Dr. Gunther considers all these stages to be merely the changing forms of 
the ordinary Cape Toad. As to whether there is any real specific difference between 
Dactylethra capensis , Cuv., D. Icevis, Gunther, and D. Mullen, Peters, does not affect 
this piece of research. The young specimens were brought by R. B. N. Walker, Esq., 
from Lagos, and those dissected by me were taken from the same bottle as those 
described by Dr. Gray (Proc. Zool. Soc. Nov. 8, 1864, p. 463, figs. 1, 2). 
These marvellous siluriform larvse appear to me to be equal in zoological and mor- 
phological value to any type whatever ; to me their only rivals are the larvse and young 
of Pipa, the other aglossal Toad. 
The youngest of the larvse brought home by Mr. Walker are figured in full (Plate 56. 
figs. 1-3) ; these are much younger than the larvae figured by Dr. Gray (Proc. Zool. Soc. 
fig. 1). The outer form of the early stages of all the Vertebrata is of great importance 
to the morphologist, and also gives the zoologist a lively idea of the relation of the 
young of one kind to the adult of another. 
In this type, also, I have had the advantage of fellow- working with Professor Huxley, 
mdccclxxvi. 4 s 
