THE NATURALIST. 



NEW SPECIES OF MOLLUSCA. 



BY W. P. COCKS, ESQ. 



Eolis Alderi, Cocks. — Body, white, opalescent, about seven-eighths of an 

 inch in length, lanceolate, tapering, pointed behind; oral tentacula, white, 

 long, slender, with yellow tips; dorsal rather shorter than the oral ones, 

 bright yellow; two rows of white branchial plumes on each side of the 

 neck, five on the back and sides; grayish with yellow tips. Found attached 

 to stones in ponds between tide marks, Gwyllyn Vase: rare, 



Eolis Couchii, Cocks. — Body, bluish black, with opaque white spots, tapering 

 behind; length, one inch and three-quarters; tentacula, white; dorsal, long, 

 filiform; oral, about one-sixteenth of an inch, shorter and stouter than dor- 

 sal; four rows of white transparent branchial plumes, spotted with opaque 

 white; each row, on the sides, composed of three foliations, semi-erect; eyes, 

 black; foot, attenuated posteriorly. I found this beautiful slug attached to 

 the under surface of a stone, on the coral bank, Gwyllyn Vase, extreme 

 low water mark, spring tide. 



Eolis glauca, Alder; var. Cocks. — Body, white, with the exception of the 

 free space between the dorsal branchiae, which was of a bright yellow colour, 

 with a light brown circular patch in the centre. Branchial plumes, long, 

 filiform, cylindrical, mottled with gray, tipped with white; oral tentacula, 

 white; dorsal, brownish, with yellow tips; length, about two inches. Pound 

 attached to the under surface of a stone, Gwyllyn Vase. 



Ancula crislata, Alder; var. Cocks. — The only difference from the Ancitia 

 cristata, was the non-retractile tentaculum that projected from the anterior 

 part of the animal, (a) It deposited ova seven days after confinement. 

 FcHmouth. 



VOL. II. B 



