36 



BOURGUETICRINUS. 



1. Bourgueticrinus Londinensis. (See Woodcut.) 



Mr. Wetherell has found fragments of a Crinoid in the London Clay at Copenhagen 

 House, evidently belonging to a species of this genus. The joints are smooth, thick, ellip- 

 tical, rounded and slightly swollen at either one or both their extremities, so as to present 

 something of a dice-box shape. They are nearly equal, and their swellings alternate in an 

 oblique manner. In the longest portion of a stem as yet discovered, measuring an inch 

 and a quarter, there are ten articulations. Each of these is, at its broadest portion, one 

 eighth of an inch in its widest diameter. The articular surfaces had a longitudinal ridge, 

 in the manner of those of the chalk Bourgueticrinus ellipticus. 



Much interest attaches to the discovery of this Crinoid. Hitherto the genus to which 

 it belongs has been known from several species found in the chalk, one found in the Eocene 

 tertiaries of Biaritz, and one still living in the seas of the Antilles, but of which, like that 

 before us, the joints only are known. No British Eocene species had hitherto been 

 discovered. 



4 C 



2 & 



EXPLANATION OF THE FIGURES. 



1. Schizastek D'Urbani. — 2 a and b. Column of Pentacrinus Sowerbu ; 2 c. Articular surface of joint. — 3 a and b. 

 Column of Pentacrinus Oakeshottianus, magnified and of the natural size; 3c. Surface of a joint. — 4 a and b. Joints of 

 the column of Bourgueticrinus Londinensis ; 4 c, joints magnified ; and 4 d, an imperfect articular surface. 



