"WOODWAED — OJS" ECHINOTKUEIA FLOEIS. 
329 
by the Rev. N. Glass, wlio has cleared it from the matrix with great 
skill and patience. It is represented by the figure marked D, and con- 
tains the dental apparatus, or " lantern," and portions of several series of 
imbricatmg plates radiating from it. At first sight, this specimen would 
seem to solve the problem, by supplying the peristome and lantern of the 
same great Cyphosoma or Diadema, of m hich !!\Ir. Flower's specimen might 
be the apex or periproct. But a closer examination confi[rms the objec- 
tions already stated, and gives increasing probability to the other conjecture 
(if, indeed, it does not compel us to adopt it), however difficult it may be 
to realize the notion of an Echinite having no proper " test," and clothed 
entirely with imbricating scales like those of the peristome of Cidaris. 
In Mr. Flower's specimen (A) the imperforate plates imbricate towards 
the centre (or apex, a), where the smaller ends of the several series con- 
verge. In Mr. Glass's specimen they slope away from the centre (or 
mouth), that is, also towards tlie apex. The perforated or ambulacral 
plates, which overlap one another outwardly (/. e. downwards) in specimen 
A, are seen in B sloping towards the dental cone, and reclining upon it. 
The portion of an ambulacrum situated between the letters a, b, c (in B), 
consists of seven plates, diminishing in size from c to a, in a line not ac- 
curately directed towards the centre. This portion exhibits the interior 
surface of the plates, known by their curved surfaces, destitute of orna- 
mental granules ; it is not, however, the oral end of one of the segments turned 
over, a thing scarcely possible to happen, for in that case the dip of the plates 
would be reversed, but it must be the opposite (or apical) extremity of a 
series folded back upon its origin, and exposed to view by the damage 
which the surface of the specimen has sustained. From this circumstance 
it seems probable that the whole fossil, when complete, was not elongated 
nor even spherical, but somewhat depressed in a vertical direction, though 
doubtless admitting of a moderate amount of flexure. At the last hour, 
after making the drawing, I ventured to clear away the chalk from the 
side of Mr. Glass's fossil (near the letter i), where an ambulacral segment 
is seen to curve as if it might be continued round to the other surface. 
This attempt was successful, for the ambulacrum and also the adjacent 
interambulacral segment {h) were found continuous, though crowded and 
displaced at the turning, falling again into regidar order, and diminishing 
in size, though not so nearly complete as in Mr. Flower's example. 
After this apparently conclusive demonstration, it appears desirable to 
give a name to the fossil, and to attempt a short description, although its 
rank and affinities are to us still matter of conjecture. At present it is one 
of those anomalous organizations which Milne-Edwards compares to soli- 
tary stars, belonging to no constellation in particular. The disciples of 
Von Baer may regard it as a " generalized form " of Echinoderm, coming, 
however, rather late in the geological day. Tlie publication of it should 
be acceptable to those who base their hopes on the "imperfection of the 
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