NASSA LIGUSTICA. 71 



Specific Gharacters. — Shell turreted ; whorls convex, flattened al)Ove, with a 

 deep suture; ornamented by longitudinal costse, 15 or more on the body-whorl, 

 prominent, obtuse, rather oblique, separated by furrows of equal width, intersected 

 by narrow but strong spiral lines continuous across the longitudinal costse, with 

 deep and narrow sulci between them; apex somewhat obtuse ; mouth suborbicular, 

 angnlated above; outer lip plicated within, corresponding with the spiral strise 

 outside; inner lip adherent to the pillar; canal short and wide, with a distinct 

 notch. 



Diiiiensloiis. — L. 22 — 32 mm. B. 1-1 — 18 nnn. 



Disfrihufion. — Not known living. 



Fossil : Waltonian Crag : Little Oakley. Miocene and Pliocene : 

 Holland, Italy. Scaldisien : Belgium, Holland. Upper Pliocene and Pleistocene : 

 Sicily. 



Remarlcs. — Of this species, characteristic of the Italian Pliocene, occurring also, 

 but more rarely in the Miocene of that region, I have found several examples at 

 Oakley. The true N. serrata has not been recorded hitherto from the East 

 Anglian Crag or from any other British deposit ; I have a few specimens from the 

 Belgian Crag, however, which seem identical with the one here figured. My 

 Oakley fossils correspond closely with some I collected years ago from the " argiles 

 bleues " of the Ligurian coast, and with the figures and description of N. serrata 

 given by Bellardi, except that they are somewhat shorter in the spire. Prof. 

 Issel has kindly confirmed my reference of the Crag shells to the species named. 

 The one given by S. V. Wood in 1848 as N. monensis, as to the identification of 

 which wdth that species he afterwards expressed some doubt,^ and is not the N. 

 monensis of Forbes, may possibly be N. serrata. The apex in the present and the 

 next species is less acute than in the prismatica group. 



With the Oakley fossil I have figured a verified specimen from the Italian 

 Pliocene. 



if 

 Nassa ligustica, Bellardi. Plate III, figs. 7, 8. 



1882. Nassa ligustica, Bellardi, Moll. Terr. Terz. Piem., pt. lii, p. 68, pi. iv, fig. 19. 



Specific Characters. — Shell ovate, conical ; whorls seven, convex, flattened above, 

 ornamented by numerous longitudinal costse, rather oblique and closely crowded 

 together, and by well-marked and strong equidistant spiral ribs, giving the shell a 

 reticulate appearance ; spire gradually tapering to a somewhat abrupt point ; 

 suture deep ; mouth suborbicular ; outer lip broadly thickened outside, denticulate 

 within ; inner lip forming a thin but rather wide glaze upon the pillar ; canal very 

 short, turning sharply to the left. 



1 Mou. Crag Moll., 1st SuppL, p. 15, 1872. 



