KONGL. SV. VKT. AKADEMIENS HANDLINGAR. BAND. 19. N:0 6. 45 



3. Conularia Isevis n. 



Pl. I figs 13—16. 



Shell regularly pyramidal, foursided, elongated and narrow. Transverse section 

 of the aperture quadrate, the four faces being of the same size or nearly so. Owing 

 to the deep fuiTOw along the uiiddle of each face the outline of the transverse sec- 

 tion becomes nearly quadrilobate. The shell substance is thicker than in anyone 

 of the other species. It is glossy, brownish yellow and an exteriör thicker stratum 

 covers the interiör one, which is paler and thinner. It is transversally wrinkled by 

 irregular folds, curved upwards in a gentle arch, sometimes large and sometimes narrow. 

 In some specimens there are only faint traces of such wrinkles and the shell is almost 

 smooth, even for long distances. The wrinkles are often not continuous across the 

 deep, longitudinal furrow, which divides each face into two halves, but are in pairs, 

 which do not always exactly correspond with each other, the opposite ones not being 

 placed on the same level. Besides these wrinkles there is no other ornamentation 

 excepting smaller and finer stria3 parallel to the wrinkles. The longitudinal median 

 furrow is, as already mentioned, uncommonly deep, but there are no vestiges of any 

 septum, connected with it on the inside as in some other species. The grooves in the 

 corners are entirely smooth and the transverse folds cease ere they reach them. 



Height of the most complete specimen 27 millim., diameter at aperture 12 millim., 

 diagonale 14 millim., diam. of the broken apex 4 millim. A fragmentary specimen from 

 a detached block of the white limestone of the stratum c measures 35 millim. in 

 length, 13 millim. in breadth. 



It has been found in several specimens in Fårö, in the limestone of Bara hill, 

 near Wisby in the middle limestone stratum, h, and in the passage bed with Ptery- 

 gotus between the strata b and c and lastly in the limestone with Rhizophyllum near 

 the church of Lau. 



This beautiful species, so dissimilar to the other Gotland species is nearly related 

 to the English Lower Silurian (Caradoc) C. lajvigata Salter Mem. Geol. Survey, III, 

 354, which, however, is rhomboidal in its section. The Bohemian C. pyramidata Hoe- 

 NiNGHAUs (Barrande. Syst. Sil. Boh. vol. III, p. 50, pl. 2 fig. 1—6) is much larger, 

 but of the same tapering, straight pyramidal form and has the wrinkles unequal. A 

 much låter species, the Gon, missourensis Swallow from the Carboniferous formation, 

 comes also very near to C. Ia3vis. 



4. Conularia Ibilineata n. 



Pl. I figs 4—8. 



Shell regularly foursided, pyramidal, but short in proportion to its broad basis, 

 Two of the sides are larger than the others and the opposite sides are of the same 



