Haasr.— Notes on Skeleton of Epiodon nove zealandiz. 485 
whilst in the South Ameriean species the anterior border is only slightly 
concave. 
Breadth, 4:60 inches, antero-posterior length on both sides of the notch, 
4:10 inches. 
The thyrohyals have a length of 6:80 inches, with their greatest breadth 
of 2:55 inches, one-third from their posterior end. 
The stylohyals are 10-80 inches long, and in their middle portion 2°10 
inches broad; they are straighter than the same bone in Epiodon australe, 
which they resemble, however otherwise in form. The whole apparatus is 
more slender than in the Buenos Aires species. 
Vertebral Column. 
The following are the numbers of vertebra :— 
ervic 7 
Thoracic 9 
Lumbar x es i s Meg uo X 
Caudal ... ica i eA m ^y D 
Total ... 4 uw 8 
In eomparing this number with that T in hi pth australe, it 
will be seen that the New Zealand species has three less, viz., 9 thoracie 
instead of 10, and 19 caudal instead of 21; thus showing also some differ- 
ence in the osteological structure of the two species. I may here observe, 
that all the plates of the vertebre are so thoroughly coalesced with the rest 
of the body, that the line of juncture is not visible—a proof that the animal 
must have been not only adult, but aged. 
Cervical Vertebra. 
Of these, the four first are entirely anchylosed, whilst the fifth, sixth, 
and seventh are free; thus having one free vertebra less than Epiodon 
australe, in which only the first three vertebre are united. However, as 
this skeleton was derived from a young animal, this difference cannot be 
claimed as of a permanent character until we know the skeleton of the same 
animal in a full-grown state. The atlas, which is 11:40 inches broad by 
8:15 inches high, forms, with the next two vertebre, one solid bone with 
a high crest. It is the largest of all the cervical vertebre. The para: 
pophyses (lower process) in each of the coalesced bones, of which that of 
the atlas is the largest, are, with the exception of that belonging to the 
the fourth, well developed. They decrease, however, gradually in size to 
the third, that of the fourth being of sueh small dimensions, that it is an 
inch shorter than the same process in the preceding one, with which it is 
anchylosed at the upper and lower extremities, but not with the body. 
The fifth cervical vertebra is very narrow, 0:55 inch ; it has, moreover, 
