96 INVERTEBRATA. 



Besides the spiral ornament already described, the whole shell 

 is covered with a delicate cross striation, running in parallel curved 

 lines between the ribs. The shell varies considerably in the deve- 

 lopment of its spiral ridges and tubercles, the median range of 

 tubercles being sometimes prominently developed. 



Measurements. Length, 23 mm. ; breadth, 17 mm. ; apicial 

 angle, 55°. 



Locality. Upware. 



Littorina Cantabrigiensis, sp. nov. 

 (Plate in., fig. 11, a, b.) 



Shell pyramidal, higher than broad, with oblique base ; orna- 

 mented with numerous tuberculated spiral ridges, and cross 

 striations. Spire regularly conic, consisting of six or seven whorls 

 separated by narrow but deep sutures. Body-whorl with a 

 distinct shoulder, in front of which the shell is rather scanty. 

 A tuberculated keel runs along the shoulder, and a second keel, 

 almost as strong, is found next in advance ; the next ridge is 

 much less developed, and then comes the sutural ridge, or a row of 

 tubercles. 



Anterior to the keels are four or five spiral ridges, where the 

 tubercles are but faintly developed. In the spire the whorls are 

 flat, ornamented with four tuberculated ridges, one of which may 

 disappear. 



Base scanty, with a small umbilical fossa. Mouth rhomboid. 



Measurements. Height, 18 mm. ; breadth, 14 mm. ; apicial 

 angle, 60°. 



The ornament structures are well developed in this shell, 

 the cross stria? between the ridges being coarser and more irregular 

 than in the other Upware species. 



Locality. Upware (very rare). Woodw. Mus. 

 N. Europe. Ocker, near Goslar (Hils Conglomerate). 



Littorina (Turbo) varicosa, sp. nov. 



(Plate in., fig. 12, a, b.) 



A turbinate shell, longer than broad, ornamented with spiral 

 ribbing and tubercles, interrupted at intervals by prominent 



