PTEROPODA. 
TENTACULITES, Schlotheim. 
The first publication, having reference to the fossils now included under 
this genus, was made by Walch in 1775. At a later period, 1784, they 
were referred by Schrceter to the genus Dentalium. In 1820 they were 
described by Schlotheim under the name Tentaculites, and considered by him 
as the appendages of Encrinites. Among the illustrations given by this 
author are forms which are clearly such appendages, and others of doubtful 
character. 
The term Tentaculites was for a long time applied to this form of organisms 
without strict generic significance, and in later times species of the genus 
Cornulites have been included under the same designation. In 1831 these 
fossils were described by Yon Buch as the spines of Leptcena lata. Goldfuss, 
in 1832, still regarded them as the appendages of Encrinites, and illustrates the 
T. amulatus and T. scalaris of Schlotheim as the extreme ramifications of the 
arms of Cyathocrinus pimatus * 
In 1832 Prof. Eaton noticed for the first time in this country a species of 
Tentaculites, which he described and figured as Echinus gyracanthus, under the 
belief that these fossils were the spines of some Echinoderm ( Geolog. Text Book , 
p. 128, pi. 1, fig. 15). This species occurs abundantly at the base of the Lower 
Helderberg (Tentaculite) limestone. 
* Brachia auxiliaria varies, form's. Under the same designation are also included what appear to be 
a species of Cornulites ; but the two species* T. annulatus and T. scalaris, are true Tentaculites in the 
restricted and accepted signification of the term at the present time. 
