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 Schiueter 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 Von Buch as the spines of Leptcena lata. Goldfuss, 

 in 1832, still regarded them as the appendages of Encrinites, and illustrates the 

 T. annulatus and T. scalaris of Schlotheim as the extreme ramifications of the 

 arms of Cyathocrinus pinnatus* 



In 1832 Prof. Eaton noticed for the first time in this country a species of 

 Tentaculites, which he described and figured as Echinus gyr acanthus, 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. 



* Brarhia auriliarin vari/B farmr. Under the same designation are also included what appear to be 

 a trades of Corkulites; but the two species, T. annulatus and T. scalaris, are true Tentaculitks in the 

 i ■•ted and accepted signification of the term at the present time. 



