Nigerian Eocene Mollusca. 29 



REMARKS. The sculpture of this shell is very striking and at once removes 

 it from V. ' conicoturrita which is smoother and more prominently spined, 

 besides having a more turreted spire with laterally depressed volutions. With 

 the exception of the protoconch, the whorls are furnished with innumerable 

 longitudinal striations crossed by strong, more or less equi-distant, spiral striae 

 mostly forming pairs, the interspaces being sometimes occupied by a single 

 striation of less strength ; this spiral ornamentation is usually the most evident. 

 The distant longitudinal costae are generally well marked and more numerous 

 than in V. conicoturrita, so that the depressed avenues between are narrower 

 than in that species. The marginal spines of the shoulder, which are smaller 

 and much less significant than those of V. conicoturrita, are continued on 

 some of the circlets below, but less obviously. In young specimens, the 

 merging of the sculpture lines at their junctions produces a series of minutely 

 rounded tubercles. 



OCCURRENCE. Cuttings Nos. 6, 10, 12, 13, 15. 

 COLLECTORS. Mr. Kitson ; Sir F. Lugard. 



Family LOTORIID^E ( = Tritoniidae). 



Hilda turrioulata, sp. nov. 



PLATE 4, figs. 24, 25. 



DESCRIPTION. Shell conico-turriculate ; spire angulate, rather shorter than 

 body-whorl, comprising six volutions, of which three constitute the protoconch, 

 protoconch smooth, sub-globular, papillose, later whorls deeply sutured, postero- 

 obliquely shelved, vertically walled in front, body -whorl of equal length and 

 width ; aperture narrowly ovate, obliquely margined in rear, contracted at base 

 into a short recurved canal ; labrum nearly vertical, strongly varixed from the 

 suture, regularly plicated within ; columella slightly excavated, well defined, 

 bearing three plications anteriorly, besides numerous short, irregular, close, 

 horizontal ridges, which cover almost its entire surface ; sculpture, consisting 

 of numerous, equi-distant, longitudinal costae, crossed by stronger transverse 

 ridges at their junctions producing minute tubercles, extremely fine, close, 

 longitudinal striations enter, also, into the microscopical structure of the test. 



DIMENSIONS. 



Alt. ... ... ... ... ... 20 millimetres. 



Lat. 10 



