HOHENWARTIANA. 327 



Aden, in debris of a small torrent. 



Zua thalassina Jouss., Bull. Soc. Malac. France vii, 1890, 

 p. 88, pi. 3, f. 12, 13. 



This smallest species of the genus is distinct by its delicacy 

 and minute size. Known only by the original figure and 

 description. 



Genus HOHENWARTIANA Bourguignat. 



Hohenwartiana BGT., Revue et Mag. de Zool., xvi, 1864, p. 

 201 (Moll, nouv., litig. on peu connes, sect. 40, p. 119) ; Mala- 

 eologie de 1'Algerie ii, 1864, p. 25, type Achatina hohen- 

 warti Rossm. Hohenwarthia Bgt. in LETOURNEUX et BOUR- 

 GUIGNAT Prodrome de la Malacologie terr. et fluv. de la Tuni- 

 sie, 1887, p. 126, substitute for Hohenwartiana Bgt. 1864. 



Shell small, very fragile, translucent and glossy, oblong- 

 fusiform, composed of 5 to 7 nearly flat whorls, the last tap- 

 ering to the base; summit obtuse, rounded. Aperture piri- 

 form, toothless, the outer lip acute, arching forward, colu- 

 mella straight, tapering or a little excised below, but not 

 really truncate, not reaching the base. Soft anatomy un- 

 known. 



Type H. kohenwarti. Distribution, Mediterranean countries. 



This group stands close to C&cilioides, from which it differs 

 chiefly by its more obese shape, approaching the genus Ferus- 

 sacia, and by the absence -of a columellar truncation. It is 

 restricted to the countries bordering on the Mediterranean. 

 As in other oblong shells in which the whorls increase irre- 

 gularly, the general shape, and the proportion of the aper- 

 ture to the whole length of the shell vary with age, so that 

 at successive stages of growth the general appearance is 

 quite different. The large number of nominal species is due 

 to this cause, to the rarity of good figures, and to the lack 

 of any ardent desire to find out what the older species really 

 are. 



The following undescribed forms are apparently referable 

 to Hohenwartiana : 



Ferussacia lierytensis Bgt., Rev. et Mag. Zool. 1864, p. 211, 

 no. 45. Syria. Name only. 



