KONGL. SV. VET. AKAJJEMIENÖ HANDLINGAR. BAND. 19. N:U 6. 83 



with their curves directed backwards. A great rnany of theiu are direct continuations 

 of the lateral, projecting lamella3, which thus run without interruptioii all around tlie 

 sliell. The whorls are in the inost perfect specimens two and a half, open, disjointed. 

 In soine, as that delineated in tigure o4, there is only oiie and a half whorls, the shell 

 resembling a Cyrtoceras. The aperture is elliptical, acuminated towards the dorsal and 

 ventral sides. The middle of the inferior lip is elevated into a small, vaulted saddle. 

 It does not, however, repose on the back of the preceding whoi'l as in tlie other spe- 

 cies. On the ventral side of the shell quite opposite to the slit band, there is a shallow 

 groove running down towards the apex. Diameter of the aperture 20 millirn. in the 

 fragment of a very large specimen. A complete specimen is 1 1 milliin. at the aper- 

 ture, the transverse diam. of the aperture is 6 millini., total length 18 millim. 



This hcautiful shell has been found in several specimens in the limestone beds 

 (b) in the neighbourhood of Wisby and towards the north as far as Likkershamu. 



2. Cyrtolites pliaretra n. 



Pl. VI figs. 39—51. 



Shell discoid, compressed, tumid along the middle-line of the sides. The orna- 

 mentation coiisists in straight, equally distantiated sulci with blunt edges, but in an 

 obtuse angle, directed forwards, near the back; they give to the surface an imbricated 

 appearance and they converge towards the ventral side. They continue without inter- 

 ruption around the shell, forming at the dorsal carina a sinus backwards and down- 

 wards. The spaces between the sulci are smooth or slightly striated by tine, longitu- 

 dinal lines. There are traces of longitudinal colour bands, alternately dark and light 

 of unequal largeness, as represented in tig. 39. The whorls are two and a half, free 

 and disjointed, rapidly increasing in width (fig, 45). The dorsal carina is low, almost 

 vanishing near the aperture, gradually increasing in height backwards and also becom- 

 ing more narrow. The aperture is ovate or in some approaching to circular, its in- 

 teriör lip reclines on the back of the nearest whorl and is, at the point of contact, 

 bent in a small saddle. Corresponding to this a groove runs on the outside of the shell 

 to the apex. The slit in the superior lip is shallow and broad. Length 15 millim., 

 longest diam. of the aperture 9 millim., transverse diam. 6 millim. 



Only found in the sliale at Djupvik in Eksta from where several specimens are 

 preserved in the State Museum at Stockholm. 



3. Cyrtolites arrosus n. 



Pl. VI figs. ,52—53. 



Shell discoid, tumid, involute, whorls three and a half, rapidly increasing in 

 size. Surface with fine, transverse, regularly curved lameilar lines, with serrulated 

 edges, as shown in fig. 53. The aperture is oval, the slit seems to have been deep 



