Mullena pa;pillbsa. 585 



orifice at both ends ; but, if the creature is carefully watched 

 for some time, it may be observed to shorten and dimple the 

 anterior by an involution of the skin, and again protrude it ; 

 and then it may, perchance, to your amazement, suddenly 

 evolve and display its circle of tentacula (b). Of these there 

 are eight large and equal, and two very small ones placed 

 together : they originate in the circumference of the cir- 

 cular lip, by a thick round stalk, which sends off numerous 

 divided branchlets, so that each assumes an arborescent form, 

 of a brown colour, speckled with darker dots. In the centre 

 of these beautiful organs we find the mouth, an aperture of 

 considerable size, and armed with an apparatus of bones 

 somewhat similar to that of those of the Echinus : it consists 

 of ten pieces, five of which seem divisible into halves by a fine 

 scarcely visible longitudinal suture, and are prolonged below 

 into two slender prongs ; but the other five which alternate 

 with them, are truncate below, being pointed above with a 

 tooth ; the first pieces having two similar teeth in close appo- 

 sition. The margins of the pieces are minutely serrulate to 

 favour their firmer union, which is principally effected by 

 ligaments ; and the whole are bound together by a strong 

 broad ligamentous band, which completely encircles them ; 

 tendons passing on the inner surface of it to the roots of the 

 tentacula, and others to and between the upper extremities of 

 the osseous pieces, for the purpose, undoubtedly, of moving 

 and contracting them. Between this band and the osseous ap- 

 paratus, there are five oblong compressed fleshy glands, free 

 beneath, but with a narrow^ pedicel at their origins, probably 

 a canal leadhig to the gullet, for these are presumed to be 

 the salivary organs, although their size and number would 

 seem to indicate a function more important to the animal's 

 welfare than the salivary glands are deemed to be in higher 

 organisms. * The stomach is placed immediately under the 

 oral apparatus : it is about half an inch in length, and very little 

 wider than the intestine, but of a whiter colour, and with 

 much stronger coats, the inner surface being strongly plaited 

 and puckered in a longitudinal direction. The intestinal 

 canal is about twice the length of the body, and must con- 

 sequently have a tortuous course ; it is furnished with a 

 narrow mesentery, is of a brown colour, equal in calibre 

 throughout, or only slightly dilated towards its termination, 

 which is circular and plain, with a stricture immediately above 

 it. The coats are smooth on both surfaces, but, under a mag- 



* [The whole assemblage of the organs which consist in any being is an 



organism.] • : 



