Sea Lilies. 7. 



type of organization for this group, and has, among other rea- 

 sons, induced zoologists to place the order Ceinoidea at the base 

 of the Echinoderm series. 



I must now ask my reader's attention to the two dried 

 Encrinites in the glazed case at the right-hand side of the 

 door. At first sight these look very much like the others, but 

 they differ from them in so many remarkable particulars that I 

 regard this species as the type of another sub-generic group, 

 and shall describe it under the name of Pentacbinus (Neo- 

 CRINUS*) decorus. 



The general arrangement of the parts of the stem is the 

 same in this species as in the last, but in the mature part of the 

 stem the joints between the whorls of cirrhi are only twelve in 

 number, and at each "node" two joints of the stem are modi- 

 fied to bear the cirrhi, the sutures between them partaking of 

 the character of a syzigie, so that the animal seems to have the 

 power of detaching itself at any of these points. The stem- 

 cirrhi, from the nature of their attachment, do not project at 

 right angles from the stem, but at once curve downwards. 

 The cirrhi are much shorter and more flexible than in P. Cajjut- 

 Medusoe. I have a beautifully perfect specimen of this species 

 before me as I write, for which I am indebted to Mr. Damon, 

 who procured it a few months ago from the seas of the outer 

 Antilles. Mr. Damon at once recognized its distinctness from 

 the more common form, and kindly forwarded it to me for 

 examination. The lower portion of the stem (which is about 

 two feet in length) is porcellanous, and covered with parasitic 

 corallines, so that the active life of this part seems to have 

 been over. The final joint (the upper joint of a nodal pair) is 

 worn and rounded. Although it was, doubtless, attached in its 

 early days, it appears to have finally parted from its attach- 

 ment, and to have led a free life. The great flexibility and 

 delicacy of the stem are suited to this change. The structure 

 of the cup is nearly the same as in the former species, though 

 the plates are different in form. The arms do not divide so 

 frequently ; there are only about thirty ultimate branches. 

 Syzigies occur at irregular intervals of a few joints all along the 

 arms, so that, while the arms of G. Capui-Medusce generally 

 arrive pretty entire, those of N. decorus tend to break into a 

 multitude of fragments. The disc is fortunately perfect; 

 instead of being closely paved, calcareous blocks like fragments 

 of perforated bricks are scattered irregularly over a naked 

 perisom. The mouth is entirely unarmed; the plates bor- 

 dering the grooves are narrow and spine-like. 



I have now described generally the structure of the two 



* Neov, recent, and ttpivov, a lily. 



