FAUNA OF THE TRENTON GROUP. 
11 
The plates above the mouth are like those in C. billing si, the an- 
terior pair between rays II and M, and III and IV being clearly 
seen, and the posterior one less distinctly. At the end of each ray is 
a small central terminal plate, suggesting the ocular of a starfish. 
This species is like 0 . chapmani, but differs from it in its larger 
size, longer and more slender arms, less circular outline, and the 
curvature of ray6 I and IV. 
Horizon and Locality. The type and only known specimen (Ho. 
7941 Victoria Museum) was collected at Ottawa by the late T. C. 
Weston in 1881, probably from the Cystid beds at the foot of Parlia- 
ment hill or from Queens wharf. 
Carney ella multibrachiata (Raymond). 
Plate HI, figure 5. 
Ottawa Naturalist 1915, 24, p. 60, pi. 1, fig. 2. 
This is a small Oarneyella remarkable for the possession of eight 
rays instead of the usual five. Rays I and V are far apart and curvo 
somewhat toward each other, thus partly embracing the anal area, 
but all the others are approximately straight. Rays I, II, and IV are 
bifurcated, I and II near the centre, and IV half-way between the 
centre and the margin. The disk is not symmetrical, ray III being 
crowded to the right of its normal position and rays I and II taking 
.up as much space as III, IV, and V. AH are short and the border 
outside them is wide, with rather large imbricating plates opposite 
the inter-arabul acral areas, and a margin of small ones outside. The 
supra-oral plates are of the simple type of C. billing si, C. chapmani, 
C. youngi, and C. pilea. Ho. 5 being a large, wide one and the two 
anterior to it small. The inter-ambulacra! areas are small, and are 
covered with small plates. Unfortunately the anal area is not well 
preserved. The type is 10 mm. in diameter. 
This form, with its numerous arms, naturally suggests Threshero- 
discus ramosus Poerste, but is really not allied to that species, which 
has three primary rays all of which bifurcate at least twice. The 
present species is much more closely allied to C . chapmani and to C . 
billingsi and when first noted several years ago was supposed to be 
an abnormal specimen of one of these species. It is iof interest to 
note that this form is found at the same horizon, the Crinoid layers 
(Hull formation) in the lower part of the Trenton, as Thresherodiscus 
ramosus, these being the oldest of the described Agelacrinitidw. 
Owing to the imperfections of the Kirkfield specimen it is not known 
how many are to be referred to this species. One seems to have only 
six rays, and it is possible all are abnormal individuals of a five-rayed 
species. 
10711 — 2 % 
