402 Mr. F. A. Bather on British Fossil Crinoids : 



after its first ossicle, and this is absolutely the only character 

 that could give rise to the idea that this specimen had tifteeii 

 arras. But this is not so rare nor even so peculiar a structure 

 as to warrant the separation of those specimens in which it is 

 found. In 136 Holcroft, for instance, an extremely normal 

 specimen of B. decadactglus, the lowest pinnule of the left 

 branch of the arm on the right is seen to bifurcate on the 

 second ossicle. This pinnule is, not only in this species of 

 Botryocrinus, but in very many pinnulate crinoids, stouter 

 than the succeeding pinnules ; its bifurcation is merely an 

 instance of reversion to the armlet stage, and is a very natural 

 occurrence in the earliest known pinnulate form among the 

 Fistulata. A far stronger case of irregular branching is seen 

 in the specimen which, in default of a better, must be taken 

 as the type of our next species ; and yet I have little doubt 

 that even this is but an individual abnormality of no specific 

 value. 



Botryocrinus pinnulatus, sp. n. 

 (PI. XIII. fig. 16.) 



This species is founded on a single specimen in the Dudley 

 Museum. It is a crown seen from the posterior, with the 

 extreme distal ends of the arms broken off, and with five 

 stem-ossicles attached. 



For the loan of this specimen I am indebted to Mr. William 

 Madeley, the Secretary of the Dudley and Midland Geological 

 Society. No locality is recorded, but from the character ot the 

 matrix, which is a soft yellowish shale, Mr. Madeley thinks 

 that it probably came from the shale between the two Wen- 

 lock limestones at the Wren's Nest, Dudley. 



This individual shows in the branching of its arms certain 

 abnormalities that might conceivably be regarded by some as 

 specific characters. I prefer, however, to regard them as 

 unessential, and to distinguish the species by characters less 

 obvious but of more permanent value. 



Specific Diagnosis. 



Dorsal cup shows slight axial folding ; R. project. Arms 

 between seven and eight times length of cup j sutures between 

 brachials almost parallel; pinnules long and fine. Ventral 

 sac very slightly ridged ; its proximal median plate wider 

 than high. 



The trivial name pinnulatus is given because the pinnules 

 are more completely differentiated than in any other species 

 of the genus. 



