IgI2.| N. ANNANDALE: The Indian Mud-Turtles. 163 
Specimen No. 1094, an articulated male skeleton, is the type 
of Theobald’s pseudo-species T. buchanam. It presents a very 
large male only slightly smaller than the one to which I have just 
referred, the bony carapace measuring 38°4 mm. in length and 
being distinctly broader than long. 
The structure of the carapace and sternum of T. hurum is 
ciosely similar to that found in T. gangeticus except that the two 
—_" 
--- = ee == : 
- a —= = 
PIG. 3.--Branchial skeleton of Trionyx hurum and T. formosus. 
A, complete apparatus (nat. size) of adult T. hurum. 
B, hypobranchial, etc. of T. formosus (nat. size). 
hyoplastra approach one another at a rather earlier stage and that 
their median processes are slighter and always single although 
distinctly bifid at the tip. 
A not uncommon abnormality, noticed in both young and 
old individuals, is the presence of three rieural plates between the 
first pair of costals. ‘This is due to the separation of a small bone, 
sometimes quite symmetrically, from the central part of the 
anterior border of the first normal neural plate. 
