1881.] THE SURVEY OF H.M.S. 'ALERT.' 33 



the narrow end, and is 2| millims. in length and 2 broad ; the 

 portion inserted iu the tissue is larger than the exposed part, the line 

 of demarcation being well defined ; the exposed tip exhibits parallel 

 lines of growth. 



Shell large, very fragile, globose, transparent liyaline, with a slight 

 milky cloudiness, exhibiting very fine strise of growth. Whorls 3|, 

 very convex, and rapidly enlarging, separated by a deep suture. 

 Spire moderately raised. Aperture exceedingly large, wider th<an 

 long, oblique. Columella very arcuate, visibly perspectively spiral 

 to the apex, coated with an excessively thin callosity. Greatest 

 diam. 25 millims., height (when resting upon the front of the body- 

 whorl and the basal margin of the aperture) 13 ; aperture 17gwide, 

 15i long. 



Hab. Station 1 ; Shell Bay {Cunningham). 



There are two species of Lamellaria mentioned by H. <fc A. Adams 

 (Gen. Rec. Moll. i. p. 201) of which I can find no published de- 

 scriptions. They are L. antarctica, Couthouy, and L. prcetemiis of 

 the same author, either of which names would be very applicable to 

 the species now described. 



Dr. Cunningham says : — " The animal possessed the power of 

 shortening and elongating the tentacles. At times it crawled along 

 the sides of the glass, filled with sea-water, in which it was kept, on 

 its large muscular foot, the shape of which underwent constant 

 changes ; and at others it floated on the surface of the water, with the 

 foot uppermost." 



COLLONIA CUNNINGHAMI, Sp. U. (Plate IV. figS. 10, 10 fl.) 



Shell small, subglobose, perforate in the young state, when adult 

 imperforate, of a rose-madder colour. Whorls A\ ; apical one 

 whitish, the rest convex and finely spirally striated, also marked with 

 faint oblique lines of growth. Suture rather deep. Last whorl ob- 

 liquely descending near the lip, somewhat flattened beneath near the 

 centre. Aperture obliquely subcircular, iridescent within. Colu- 

 mella pearly, spread over the umbiHcus. Labrum with a narrow 

 pinkish margin within. Height 4i millims., greatest diam. 5, smallest 

 diam. 4^. 



Operculum circular, consisting of six whorls, which are most 

 easily seen on the inner suface. The outside is somewhat thickened 

 by a shelly deposit. 



Hab. Stations 5 and 2, and Wolsey anchorage, 17 fathoms, mud 

 and gravel bottom. 



Named after Dr. K. O. Cunningham, whose labours on the 

 Patagonian fauna are well known and highly appreciated, 



Trochus (Photinula) c^rulescens. King. 

 Hah. Stations 6 and 7. 



Trochus (Photinula) violaceus. King. 

 Hah. Stations 2, 5, 6, 7, and Puerto Bueno, 2-7 fms, 

 Proc. Zool. Soc— 1881, No. III. 3 



