534 TEST ACE A ATLANTIC A. 



Fam. 2. HELICID^E. 



Genus 2. HYALINA, Gray. 

 ( Liwilla, Lowe.) 



Hyalina spurca, 



Helix spurca, Sow., in Darwin's Vole. Isl., Append. 157 



(1844) 

 Forbes, in Journ. Geol. Soc. Lond. viii. 199. 



t. 5. f. 10 (1852) 



Pfeiff., Mon. Hel. iv. 324 (1859) 



Melliss, St. Hel. 120 (1875) 



Habitat in solo eonchylifero, versus borealem insulse ; semi- 

 fossilis. 



Although not a syllable is said about the affinities of this 

 Helix in the notices to which I have access, yet the figure of it 

 which is given by Professor Forbes seems to me to imply that 

 it mast be very closely related to the common Hyalina cellaria. 

 True it is that the shell is drawn in a position which unfortu- 

 nately does not permit a view of its umbilicus (which is said, 

 however, by Sowerby, to be small and deep) ; but its discoidal 

 aspect and general contour are so remarkably suggestive of the 

 (nevertheless comparatively gigantic) European H. cellaria, 

 which abounds in the intermediate districts of St. Helena, that 

 I scarcely think I can be far wrong in placing it as I have. 



The H. spurca, which occurs, in company with other sub- 

 fossilized species, near Flagstaff Hill, in the extreme north of 

 the island, and which measures only about two lines across its 

 broadest part (with an altitude of one line), appears to be rare. 

 Sowerby's diagnosis of it is as follows : ' T. suborbicularis, spira 

 subconoidea, obtusa ; anfractibus quatuor tumidis, substriatis ; 

 apertura magna, peristomate tenui ; umbilico parvo, profundo.' 



Hyalina dianae. 



Helix Dianas, Pfeiff., Mai. Bldtt. iii. 206 (1856) 

 Id., Mon. Hel. iv. 103 (1859) 

 Id., ibid. vii. 179 (1876) 



Habitat in editioribus insulse ; ad montem excelsum 4 Diana's 

 Peak ' dictum a Dom. Cutter (sec. Pfeiffer) reperta. 



Judging from Pfeiffer's diagnosis, this little Helix would 

 appear to belong to the recent fauna ; indeed if its habitat, 

 ' Diana's Peak,' is to be trusted, it could scarcely be otherwise, 

 for there are no subfossiliferous deposits on the great central 

 ridge. It is a minute shell, like the //. spurca, only about two 



