114 
PALAEONTOLOGY OF NEW-YORK. 
The closely arranged branchlets, near the summit of the column, cover and 
obscure the structure of the base of the specimens figured. The arms are not pre¬ 
served entire ; but from the gradually tapering form and small joints, we may 
infer that they continue simple above the first bifurcation. In the specimen (fig. 3) 
which preserves a part of the proboscis, the anal plates are conspicuous, while their 
connexion with the proboscis is destroyed, and only the upper portions are preserved. 
The whole specimen has been much crushed, and the arms and tentacula are in¬ 
volved with the crushed proboscis. 
Fig. 1. A specimen preserving a part of the column, with the branchlets broken off. The 
body is too imperfect to be represented in detail, but the arms and tentacula 
correspond to those of fig. 2. 
Fig. 2. An individual nearly entire,‘with a small portion of the column and branchlets 
attached, and nearly covering the body. The arms are preserved nearly to their 
extremities. 
Fig. 3. An individual much crushed, showing the structure of the body and a portion of the 
proboscis. The small point for the attachment of the column is well shown in the 
figure. 
Fig. 4. Enlargement from fig. 2 of the first and second radial plates, the first arm joint, and 
succeeding plates of the arms and tentacula. 
Fig. 5. Structure of the body and base of arm, from fig. 3. 
Geological position and locality. In the shaly partings of the Pentamerus lime¬ 
stone of the Lower Helderberg group : Jerusalem hill, Litchfield, Herkimer county. 
Platycrimis parvus (n. &.)- 
Plate IY. Fig.. 6-9. 
Body very small. Basal and first radial plates obscure. Second radial plates 
filling the excavation in the upper margin of the first radial. 
Arms bifurcating upon the first brachial plate, and continuing simple to 
their extremities : joints of the arms about as wide as long, giving 
origin to one or two tentacula on each side. Tentacula composed of 
rounded joints, which are about as long as wide. 
Column round, slender; consisting, near the body, of alternating large 
and small joints, and below, of a greater number of small joints al¬ 
ternating with the larger ones. The large joints give origin to long 
slender branchlets which are closely 'clustered around the body, and 
