DEVELOPMENT OF THE SKULL IN THE BATRACHTA, 
247 
13. The solid basi-branchial bone. 
14. The variation in some of the investing bones— 
a. Breadth of fronto-parietals. 
b. Great size of nasals. 
c. Feeble upper part of the long squamosals. 
cl. The great breadth of the parasphenoid. 
e. The thin, shell-like, toothless vomers. 
All these things seem to prove that Callula is far removed from the typical 
Batrachian. 
Second Family. Hylaplesid^e. 
Ear perfect; toes free ; sacral apophyses cylindrical; no parotoids. 
Genus Hylaplesia. 
73. Hylaplesia tinctoria. —Adult female ; inch long. South America. 
This is a long skull (Plate 44, figs. 1-7), the breadth being, contrary to rule, less 
than the length, or as 8 to 9. Its cheeks are very feeble, slightly bowed, but the 
cranium itself is very broad, and altogether forms an irregular oblong. 
The quadrate condyles have only got as far back as the space between the Eustachian 
openings and the stylo-hyals (figs. 2 and 3, q.c., eu., st.h.). The breadth across the 
ethmo-palatines is three-fourths that across the quadrate hinges. The breadth across 
the ethmoidal wings, excluding the ethmo-palatines proper, is but little less than the 
breadth of the roof at the temporal angles ; the roof is lessened very little, forwards ; 
its orbital edge is gently sigmoid, as it narrows from the temples, then widens, and 
narrows again in front. The muzzle is by far the broadest I have seen; yet the 
nasal region is of normal length —or antero-posterior extent; but the breadth is just 
twice as great, so that the terms should be reversed. As in several of the “ Caduci- 
branchiate Urodeles,” the endocranium is one continuous bony trough, for cartilage 
only remains as the occipital condyles ( oc.c .); as the tegmen tympani (fig. 1, t.ty.) ; the 
facet for the pedicle (pd.) ; as a circle round the very small optic fenestra (II.); and in 
the fore and under parts of the transverse muzzle (px ., s.n.). The strength of the 
cranium is in great contrast witli the weakness of the face ; in the former, anchylosis 
has obliterated most of the landmarks, yet the fronto-sagittal suture is only lost behind 
(fig. l,fp*). 
I can only do justice to this abnormal skull by comparing it with those of the two 
“ Aglossal” types, Pipa and Dactylethra (see Phil. Trans., 1876, Plates 56-62). 
As to the skull, there is no type amongst the tongue-bearing Frogs and Toads equal 
to this for softening down the hard distinction between them and the two tongueless 
“ waifs ” that make up the sub-order “ Aglossa.” 
* This suture is too strongly marked, behind, in the figure, and so also is the slight ridge along the 
ethmoid. 
