102 CLEIOCEIXUS. 



lings's Fig. 1 c the upper ring and some plates from the next ring above 

 it were crushed in over the basal cavity, and cemented with a very fine, 

 shaley matrix. If these could be removed, without destroj-ing the rest, we 

 might see what lies next to the column. The small size of the specimen, 

 and the uncertainty as to how the fractures might run, rendered .the opera- 

 tion a delicate and risky one to undertake with a type specimen ; but I 

 thought the benefit to be gained in case of success would warrant the 

 risk. 



I accordingly laid the matter fully before Dr. Whiteaves, and requested 

 his authority to undertake it. This he gave without hesitation, and in the 

 most liberal manner, leaving me free to act with the specimen as if it were 

 my own. I wish here to express not only my grateful acknowledgment for 

 the personal confidence reposed in my judgment in so delicate a matter, but 

 also, in view of the important result attained, my thanks as a palaaontologist 

 to Dr. Whiteaves for the benefit he has conferred upon science, by furnish- 

 ing the means of information which, in my opinion, there was no hope of 

 obtaining in any other way. I give this opinion, not only on account of 

 the rarity of the specimens, but of their poor preservation. In all others 

 that I have ever seen the calcareous test is soft and friable, and the sur- 

 rounding matrix adheres to it so closely that any kind of fine cleaning is 

 impracticable. 



The work of removing the necessary plates and debris from above the 

 base of the specimen was tedious and difficult, being performed entirely 

 under a ten-power dissecting microscope, with tools specially fashioned out 

 of needles and fine steel pens. It was completely successful, however, 

 without any mishap, and disclosed a structure most extraordinary and 

 anomalous, unlike any of the previous suppositions, and wholly at variance 

 with that of any other known Crinoid. 



Instead of two, there is only one ring of plates inside of the proximal 

 ring of so-called radials and interradials, which are seen on the outside and 

 surrounding the column. The axial canal is very large, and obscurely pen- 

 tagonal ; and around it, resting on the column and occupying its full thick- 

 ness, are five large, strong, quadrangular plates, sloping from within upward 

 to a thin upper face, radial]?/ situate, which are followed by the first and 

 second primibrachs, not alternating with them but in direct succession, 

 without the interposition of other plates. The first plate visible externally 

 in the radial series is not, as a rule, visible at all from the interior when all 



