54 
sort of proboscis for the sucking in of food. It spreads over the sulcated part 
of the arms, hands, fingers, and tentacula, concealing under it nourishing ves- 
sels, which may be sometimes traced spreading into the muscular integuments 
between the fingers. The arrangement of its calcareous plates is peculiarly 
elegant in the tentacula (PL. 1. fig. 6. and 7.) where they form two series an- 
gularly pointed at their inner edge, thus producing a serrated line of insertion 
between each other. Their minuteness may be conceived from the observation, 
that from ten to twelve are necessary to cover the excavated canal of a single 
tentacular joint, which, taking the amount of these, would require about 200 
plates for each full grown tentaculum, 
I have in vain endeavoured to trace apertures at the terminating points of the 
fingers and tentacula, although Gueraxp alleges, that here orifices existed serv- 
ing as mouths to the animal for the taking in its food. It appears probable to me 
that from this assertion M, Lamarck derived his generic character of Ex- 
crinus. ‘ The branches forming the umbel are filled with polypi in rows.” 
The late Mr. Tontn’s specimen, is in another point highly instructive. 
The animal must have suffered material mutilation previously to its having been 
taken from its marine abode, and hence affords a striking illustration of its 
power of reproducing lost parts, to which I alluded when speaking of the auxi- 
liary arms ; the most surprising instance of this, is, that the animal has repro- 
duced from one of the scapula two new arms (Pt. 1.) each having its two hands 
and six fingers, but as yet not an eighth part the size of the full grown ones. 
They are highly muscular, and prove the gradual developement and formation 
of the calcareous joints in the manner which I have endeavoured to explain, 
when speaking of the superior portion of the column and the formation of the 
auxiliary side arms. The pointed termination of the fingers is coiled, which 
demonstrates the greater sensibility and flexibility of this part during the life of 
the animal. The new formed arms protrude from near the inner concave or 
channelled margin of the scapula over the central perforation, leaving the 
rest of its slanting surface covered by a conspicuous yellow brown epidermis, 
In a few other instances, new formed fingers proceed from the cuneiform joints 
in different stages of growth, sometimes almost assimilating in size with those 
whose place they now supply. In one case two joints of a finger have been 
broken transversely on one side, their parts somewhat displaced, and the frac- 
turehealed by new secreted matter. ‘The effects of au injury sustained by the 
investing membrane of the column, and the consequent irregularity of the 
