Mr. W. Clark on the Aninial <;/ Deutalium Tarentinum. 327 



it is not however placed, as in tliem, immediately at the anterior 

 orifice of a pharyngeal oesophagus leading to a stomach and 

 fixed thereto by strong elastic threads, but it is the stomach 

 itself most slightly attached to the membrane which envelopes 

 it. This powerful machine undoubtedly acts as a gizzard to 

 grind the testaceous food of this animal; it empties itself by 

 a very short scoop- shaped canal into an intestine of three or 

 foui' intricate gordian knot-like folds, which, strange to say, 

 often contain a dozen or more shells that have escaped the 

 action of the gizzard ; the intestine does not entwine with the 

 liver, but is inclosed within the same cavity as the gizzard ; it 

 pierces its iaclosure on the right side, passes through the liver, 

 and discharges the rejectamenta at the base of the branchial ca- 

 vity under the mantle about the middle of the shell, from whence 

 they are passed by the deep groove of the foot, which the animal 

 can by the compression of its sides make canaliferous, as far as 

 the middle section of the foot, around which, when the animals 

 are fresh from the sea, they form repeated collars of mucus, 

 which in a short time, from frequent aggregations of matter, 

 become ponderous, break and fall off", and when examined are 

 found to be composed of the spoil of shells : this circumstance, 

 independent of all others, shows that the faeces are not discharged 

 posteriorly. 



The liver is an extremely scanty light yellowish green organ 

 placed under the stomach, and is continued under the branchial 

 cavity, and then joins the ovarium, with which it becomes almost 

 imperceptibly amalgamated throughout its whole length. The 

 ovarium is very long and large, and fills up the whole of the poste- 

 rior part of the body from the branchiae ; it consists of from four 

 to six longitudinal rows of distinct granular yellowish white 

 masses of ova, with scanty interweavings of the liver, which ex- 

 hibit three stages of development ; the more forw ard ones become 

 broken into six portions, and when ready for exclusion these 

 again break into perfectly round, pale brown globules ; all these 

 phases vary in difibrent animals according to the advancement 

 of fecundation. The oviduct is in the centre of the longitudinal 

 rows of ova formed by their junction, and the ova are undoubt- 

 edly discharged by the posterior spoon-shaped process, from 

 whence I have seen volleys of fifty or a hundred ejected with 

 considerable force in minute round points : these must not be 

 mistaken for faecal pellets, neither must the oviduct be con- 

 founded with the branchial canal, which is the cavity formed 

 between the mantle and the membrane of the ovarium. The ho- 

 mogeneity of the masses of this part of the body in many con- 

 ditions, especially when fecundation is not far advanced, renders 

 the discrimination of organs of this character a matter of some 

 difficulty. I have not discovered any exserted organs of repro- 



