PTEROPODA. MASSY. 



sixth difference (<y. <//. p. /) refers tc> variations in ihc teeth. Sii-C. Klioi found the 



base cil' the median tooth in I., iinliin'lii-'i { lie lairlv sirai'dif. while in /-. In-ln-uni il 







was hollowed out almost into a horse-shoe shape. With regard to this I found thai 

 even in the same specimen the median teeth varv between these two forms according 

 to the position in whieh they happen to lie placed on the ,-lide. Yayssiciv (I9I.">. 

 pi. XI. tigs. i'ts and - _'ls his) shows the convex and concave aspect of a median tooth 

 of L. helicoides, Jeff. : which indicates \er\- well the difference which occurs in regard to 

 the liasal part of this tooth in /.. ln-lif'nin. according to llie posiiion in which it is 

 placed on the slide. A specimen of 4'jU mm. in diameter showed a radiila containing; 

 fifteen rows with eleven lateral teeth on either side. A median tooth measured I'.is // 

 and a lateral one I C>4 /a. With regard to the shells of the present species it may be 



worth noting that some were <|iiite transparent and 

 some ([iiite opaipie even when occupied hy their 

 owner. In the whole of this vast collection only 

 one case of abnormality was observed. A very young 

 specimen i'rom Station ~1'1'.\ possessed tins joined 

 together at their tips (Fig. >). 



Dixtrihntion. - Arctic and Antarctic regions. 

 This species seems onlv able to exist in very cold 

 water but follows the Labrador current down to 

 38 N. It has been recorded as Linnti-lnii /n'iji<;/. 

 Dull, from Neah Bay, 48-49 N., mid at :!<) N. ai 

 Monterey, having evidently followed the cold Van- 

 couver stream which stretches along the coast of 

 California. Munthe (1887) has recorded it from the 

 middle of the Atlantic at 35 30' N., and 43 30' \V. 

 Meisenheimer (1905, p. 7) suggests that this excep 



Individual with abnormal fins tional circumstance is probably due to the melting of 

 joined at the tips, X 32: B., c , n , .,. . , , . , . - 



balancer ; F., fins ; T., tentacles. lce ^ >m southwardly drifting icebergs wind,, mixing 



with the water of the warm currents of this region. 



would cause especially favourable conditions. In the Antarctic regions, where \ ayssieiv 

 (1915, p. 124) thinks it is not indigenous but has been accidentally introduced by 

 marine currents, it has been observed as far north as 35'~ to :l| S. (Meisenheimer. 

 1905). 



14. Limacina inflata (d'Orb.). 



Mlnilii uijl'itit, d'Orb, 1847. 

 ,Sy.//-/./// rnal niHs, Souleyet, 18^tn. 

 Llwiii'iiiii >viiy-/in/(/ri(, A. Gould, IS.IL'. 

 Protomedea data, Costa, IStil. 



roBtrullg, P. Fischer, L882. 



J.luiiii-nin nill'iln, l?oas, ISSI',; P. Pelsenrrr. 1SSS; Tcsrli. I'.lll); Mri-, nliriiiM-r. I'. Mi:, ..,i,,| 

 1906; Uniini'vif, ]'.i|:>: Vayssii'-rc, I'.M:', and 1915. 



VOL. II ! 1. 



Fic. li. -l.iiiitii-iiKi lii'lii-iini (Phipps). 



