68 Miscellanea Zoologica. 



is certainly dependant on the will of the animal, for I have repeat- 

 edly seen it begin and stop, and be again renewed after an interval 

 of repose, and again be checked in a manner that could leave no 

 doubt but that the play of the organs was entirely voluntary. The 

 cilia of the antennae, notwithstanding the larger size of the organs, 

 are less than half the length of those of the branchiae. 



Leucodore ciliatus lives between the seams of slaty rocks near 

 low-water mark, burrowing in the fine soft mud which lines the fis- 

 sures. Its motions are slow. When placed in a saucer it keeps it- 

 self rolled up in an imperfectly circular manner, lying upon its side, 

 and the painful efforts made to change its position, and with little 

 or no success, shew too plainly that it is not organized to creep 

 about like the Annelides errantes, but on the contrary that its pro- 

 per habitat must be a furrow similar to those of the Tubicolous 

 worms, to which, in structure, it evidently approximates in several 

 particulars. 



Plate III. Fig. 1. Leucodore ciliatus of the natural size. 2. The 

 same magnified. 3. An antenna more highly magnified. 4. The 

 bristles of the fifth segment. 5. A branchial process separated to 

 shew the cilia. 6. A few of the oviform bodies which lie between 

 the intestine and skin. 



III. Nerine,* Johnston. 



Character — Body vermiform, subquadrangular : head small, 

 distinct : mouth sub-inferior, with a very short edentulous proboscis : 

 eyes minute : antenna: two, occipital, large, long, tapered: branchiae 

 forming an uninterrupted series of short tapered ciliated filaments 

 along each side refected on the back, with a lobe at their base : feet 

 all alike, roell developed, biramous, each branch consisting of a com- 

 pressed lobe and a short pedicle armed with simple bristles : anus 

 stellated. 



Observations. — The body of the Nerines is elongated and ver- 

 miform, narrowed a little at the head, and tapered gradually to- 

 wards the anal extremity. It is somewhat quadrangular, and is 

 formed of numerous narrow segments. Each segment has on each 

 side, affixed to its dorsal margin, a subulate branchial process, as 

 long as the semidiameter of the animal, and of a fine red colour, 

 which proceeds from two large blood-vessels running up within it. 

 A cuticular fold or membrane invests the base of each branchial 

 filament, and mounts along the side to an extent which varies with 

 its position ; for on the filaments of the anterior third of the body 



Nerine, a patronymic of the daughters of Nereus. 



