32 PROF. A. DEKDT ON THE 



I have observed in these in Caudina are suggestive of those dis- 

 covered and more fully investigated by Hardy * in the Crustacea. 



CucuMAEiA. HuTTONi, u. sp. (PL 3. figs. 19, 20.) 



Body cucuniiform, bluntly rounded in front, more tapering 

 behind ; posterior extremity slightly turned up dorsalwards. 

 Integument smooth, but hard and thick, with minutely but 

 distinctly scaly apj)earance, owing to the presence of over- 

 lapping calcareous plates, Avhicb are distinctly visible to the 

 naked eye. No distinct teeth or papillae around mouth or anus. 

 Length of body a little more than 3 inches, diameter in the 

 middle about two-thirds of an inch. 



Tentacles copiously branched, dendriform, ten in number. The 

 raid-ventral tentacle is longer, and that on each side of it shorter^ 

 than any of the others ; the mid-dorsal is also perhaps rather 

 shorter than the lateral tentacles, but all are well-developed. 



The body when fresh is of a pale greyish-yellow colour. The 

 tentacles are abundantly speckled with brown. 



The ambulacral appendages are very feebly developed. Three 

 irregular, multiple, but rather scanty rows of small pedicel* 

 (P any fully developed tube- feet) are visible on the ventral ambu- 

 lacra, in the middle part of the body. None are visible on the 

 dorsal surface. Dissection failed to reveal the presence of any 

 ampullae. 



The five longitudinal muscles are undivided and powerfully 

 developed. The retractors of the pharynx are remarkably strong, 

 and spring from the corresponding longitudinal muscles at about 

 one-third of the distance from the anterior to the posterior 

 extremity of tbe contracted animal. 



The pharynx (PI. 3. fig. 19) is very large and consists of two dis- 

 tinct parts. The anterior part is about half an inch in length,, 

 eversible, muscular and soft-walled. The posterior part is about 

 an inch in length and is supported by the very strongly developed 

 calcareous ring, to the radial pieces of w^hich are attached the 

 retractor muscles. The tentacles are attached at the junction of 

 the anterior and posterior portions of the pharynx, a little in 

 front of the retractor muscles. In the retracted state they point 

 straight backwards, and are thus lodged in the posterior part of 

 the pharynx, which they completely fill. 



The calcareous ring (Pi. 3. tig. 19) is very complex, and consists- 

 of ten compound pieces. The radial pieces are rather narrow, but 

 * Hardy, W. B. Journ. of Physiol, vol. xiii. p. 165. 



