from the Kimmeridge Clay of Weymouth. 27 



The rays, in consequence of the numerous subdivisions, were 

 probably, in the perfect specimen, fifty or more in number. 

 The delicate pinnules or tentacula with which they are fur- 

 nished are not closely arranged, but attached to every alternate 

 joint ; they are about fa of an inch in length, flattened, angular, 

 and curved, consisting of about eight elongated joints (fig. 1 /). 

 The column or stem is composed of pentagonal plates of nearly 

 equal thickness, each having a star-like, crenated articulating 

 surface (fig. 1 i, f), the external face of each angle being orna- 

 mented with a faint band of bead-like markings, which be- 

 come strong ridges accompanied by a central depression or pit 

 towards the upper portion of the stem. At variable intervals, 

 generally about the eighth joint, spring the ramules or auxiliary 

 side-arms, five in number, developed from an articulating sur- 

 face between each of the angles of a joint (fig. 1 j) ; in the 

 specimen under consideration they are mostly broken off near 

 the base ; the portions which remain show that they were round 

 and closely jointed ; one of these articulating surfaces may be 

 seen in the enlarged figures of portions of the stem (figs. 1 h 

 and e). 



The plan of the arrangement of plates composing the calyx 

 (fig. 1 c) is taken from a well-preserved and larger specimen, 

 which is quite relieved from the matrix, exhibiting most per- 

 fectly the whole of the plates of the head, with the lower sub- 

 division of the arms, their upper portions being imperfect 



(fig. i by 



Affinities and Differences. — This species somewhat resembles 

 Pentacrinus Milleri, Austin, but differs in the following parti- 

 culars : — it is of more delicate proportions ; the branching of the 

 rays takes place at longer intervals ; the tentacles are not so 

 closely set ; the column has sharper angles and square sides ; 

 whilst in P. Milleri the angles of the pentagonal joints are much 

 rounded and very prominent, and in our species the ramules are 

 situated at greater distances. Pentacrinus scalaris, Goldfuss, 

 said to be a synonym of P. Milleri, is a species founded upon 

 portions of the stem only ; in some of its varieties, as figured 

 by Goldfuss, it bears a considerable resemblance to the stem of 

 P. Fisheri : it is, however, considered by good authorities to be 

 identical with P. Milleri, from which our species is certainly 

 distinct. 



Locality and Stratigraphical Range. — This interesting addi- 

 tion to the Echinodermata of the Secondary Rocks was dis- 

 covered by the Rev. Osmund Fisher, in the Kimmeridge Clay, 

 at Green Hill, Weymouth, Dorsetshire. It was obtained from 

 a bed of dark-blue clay, the surface of which was covered 



