HELIX- JACOSTA. 181 



pointedly egg-shaped, distinctly lunate, excavated at the position of 

 the keel and channelled within ; the peristome is acute having a 

 strong white lip within ; the upper margin is somewhat produced 

 forward, lower margin slightly reflected, a little dilated at insertion. 

 (Kob.). Alt. 6, greater diam. 12J, lesser 11 mill. 



Sitia, Crete. 



H. (Jacosta) amphiconus MALTZ. Nachrichtsbl. D. M. Ges. xv, 

 p. 103, 1883. KOBELT, Kossm. Icon. n. f. iv, p. 25, f. 546. 



A very elegant species, resembling H. elegans in form, but ribbed 

 as in Jacosta. 



H. SIDERENSIS Maltzan. PI. 40, figs. 72, 73, 74. 



Shell depressed, peculiarly obliquely perforated, the perforation 

 transversely enlarged at the last whorl ; closely finely striated, 

 strong, but not thick. White with very distinct dark brown bands 

 of which generally but one is upon the upper side and three to five 

 upon the base. The spire is flatly convex with minute dark brown 

 apex ; there are five regularly increasing whorls, separated by the 

 impressed suture which is seen to be very finely and irregularly 

 crenulated viewed under the lens ; the upper whorls are but slightly, 

 the following somewhat more strongly convex ; the last is rather 

 broadened and more or less distinctly, bluntly, angularly flattened 

 above toward the suture, and more so upon the under side ; 

 suddenly deflected in front. Aperture but slightly oblique, trans, 

 versely ovate, having a more or less distinct angle outwardly- 

 moderately lunate; the peristome is acute having a very distinct lip 

 within ; the converging margins are joined by a quite thin callus, 

 the upper straight, somewhat produced forward ; the columellar 

 margin is very slightly reflected, scarcely dilated at insertion. 



(Kob.~). Alt. 6, greater diam. 11 J, lesser 10 mill. 



Sidero Mts., Crete. 



H. (Jacosta') siderensis MALTZ., Nachrichtsbl. D. M. Ges. 1883, 

 p. 104. KOBELT, Rossm. Icon. n. f. iv, p. 26, f. 517, 518. 



Very distinct in the peculiar perforation, as in H. (Carthusiana) 

 obstructa Fcr. 



H. SPRATTI Pfr. var. PERPLANATA Pils. PI. 45, figs. 12, 13, 14. 



More depressed than typical spratti, the spire flat, upper surface 

 of whorls having a very strong central revolving rib. Umbilicus 

 wider and more open. 



Alt. 4, diam. 11 mill. Sicily (Benoit.) 



Cf. Westerlund, Nachrichtsbl. 1892. 



