of British Mollusca. 135 



3. MangiUa costata (Donovan) . 



Var. coarctata^ Forbes & Hanley. 



4. MangiUa rugulosa (Pliilippi). 



5. MangiUa hr achy stoma (Pliilippi). 



6. MangiUa nebula (Montagu). 



Var. 1. elongata, Jeffr. 



Much larger, | inch long, pale in colour ; ribs 

 little raised ; spiral striee faint or absent. Bantry 

 and Shetland {A. M. N.). 



Var. 2. Imvigata^ Pliilippi, = P^ewro^oma lasvigata^vax. 

 minor (Jeffreys). 



" Anfractibus planiusculis, contiguis, laevibus, sub 

 lente tenuissime striatis, superne obsolete plicatis j 

 apertura oblonga, tertiam longitudinis partem 

 ffiquante ; cauda brevissima " {Philippi). Ribs of 

 last whorl evanescent or absent. 



Var. 3. vittata, Norman, = P/ewro<oma Icevigata, Jef- 

 freys (partini). 



" The space below the suture is girded by a 

 thickened rim, and is always ribless " {Jeffreys) . 

 Jeffieys's var. minor is no doubt the true Icevigata; 

 but this remarkably fine shell, which he and I took 

 together living between tide-marks at Belgrave 

 Bay, Guernsey, and from which his description of 

 Icevigata was taken, differs much more widely from 

 the typical nebula than do the true Icevigata. It is 

 like Icevigata in general character, but attains a 

 large size, '6 inch, and has a marked rounded 

 smooth fillet passing round the summit of each 

 whorl and projected over the preceding one. I 

 have seen nothing like this in Mediterranean Icevi- 

 gata, examined from many localities, nor is this 

 tillet described by any other writer. 



Var. 4. lactea, Jeflfreys. 



Subgenus 1. Pleukotomella, Verrill. 

 7. MangiUa Packardi, Verrill. 



Pleurotomella Packardi,Yei'n\\, Amer. Journ. Sci. v. p. 15 (Dec. 1872) ; 



Trans. Conn. Acad. vol. v. p. 453, pi. xliii. tig. 9, pi. Ivii. fig. 5, 



vol. vi. p. ^65. 

 Defrancia formosa, Jeffreys, Proc. Zool. Soc. 1883, p. 397, pi. xliv. 



fio-s. 0, 9 «, 9 6 ; Watson, Kep. ' Challenger,' Gast. (1885) p. .349. 



