Cr'^itiix Tmtdcroinei'K III. — (riK/m. 171 
of transition limestone or by a l)and of l)reeciated limestone rock; 
and that in no place does the limestone change from Ijlue to white 
across a continuous exposure without one of these transition rocks. 
NEW OBSERVATIONS ON THE GENUS TRINAC- 
ROMERUM. 
By F. W. ('KA<iiN, Colorado Spriiiijs, Colorado. 
The type- skeleton of this genus, discovered in the summer of 
1888, and partially described by the writer a few months later*, 
was nearly perfect when first seen b}' the workmen who found it, 
but was afterward broken in pieces by vandalic curiosity seekers, 
and had been scattered over portions of two counties before it 
came to the writer's knowledge. It was with great difficulty that 
the task of getting together such parts as had escaped utter de- 
struction was accomplished, some of these lieing oljtained by rock 
excavation at the original locality, others by dint of considerable 
perseverance in travel and moral suasion. 
The expenditure of much time and labor in freeing the bone- 
fragments from the more or less silicified limestone matrix and 
in matching them, has resulted in restoring to a condition avail- 
able for study, several parts which once seemed hopelessly in- 
complete. A study of the type, as thus renovated, and of parts 
of several other specimens, has enabled me to supplement my 
preliminary paper with the following descriptive notes. 
The Skull. — Besides the very imperfect skull of the type 
( represented by the muzzle and a number of other fragments, of 
more or less importance ), the writer has secured two skulls which 
belong — onet certainl}', the other probably — to this genus. For 
convenience of reference, these three skulls may be designated 
respectively as A, B, and C. 
As all preserved parts of the skeletal structure of Triuacromr- 
i-um will be fully treated in an illustrated memoir, which is in 
preparation, a detailed consideration of the skull will not now l)e 
undertaken; l)ut a few of its more conspicuous features mav here 
be noted. The skull is very large ( B, C ) and lono- ( A, B ), 
^Preliminary Description of a Xew or Little Known Saurian from the 
Benton, of Kansas. American (xeologist, December, 1«88. 
tThis skull seems to have pertained to an individual of about the same 
size as the type, with wliicJi it agrees perfectly in several parts pre- 
served in both specimens. I regard it as not only congeneric l)ut also 
co-specitic with the type. 
