44 G. LINDSTRÖM, ON THl': SILURIAN GASTROPODA AND rTEROPODA OF GOTLAND. 



the »Dictionnaire des Se. Nat.» where it is stated that De France lias iiaincd it. I 

 only lind in vol. 32 p. 193, artide »MoUusques», wliieh is entirely writteu by Blain- 

 viLLE, »Conul. Sowerbii Dkfii. Diet. des Se. uat., Fossiles», but on turning to that 

 article nothiiig at all is found coneerniiig Gonularia. The aceompanying figures are 

 exact copies from the Mineral Conchology of Sowerby of his C. quadrisuleata, whieh 

 no doubt is a Carboniferous speeies. C. Sowerbyi is consequently a synonym of this 

 species and not of the Silurian one. When thus neither the name C. quadrisuleata 

 nor C. Sowerbyi can be employed, we are obliged to adopt the next in chronological 

 order and then we have three deseribed, all at the same time, by Såndbekger. But 

 these three species, cited above, are only synonyms. Of these I have chosen C. can- 

 cellata as being given to the species of the »Silurian System». C. curta has the prio- 

 rity but is very unappropriate and seems to be founded on a spurious specimen. As 

 Salter, App. Brit. Pal. Fossils p. VI, remarks, the Devonian C. Gerolsteiniensis d'Arch. 

 & Vern. is so nearly related to this, that it may be considered as a variety. 



Amongst the American Conulariai, deseribed by Hall, C. trentonensis, Pal. N. 

 York vol. 1 p. 222, possibly is the same as Gon. cancellata. See also Eichwald Leth. 

 ross. 1 p. 1057 on Gon. trentonensis. 



2. Gonularia monile n. 



Pl. I, figs. 9—12. 



Shell formed as a regular, foursided, narrow and elongated pyramid. The trans- 

 verse section of the aperture is a regular quadrate having each of its corners inflected 

 by a groove. The shell substance is comparatively thicker in this than in the other 

 species and consists of an exteriör, darkly coloured sti-atum, which is thicker than the 

 interiör thin and påle one. The ornamenting, transverse ridges, of Avhich eight are 

 contained within a length of 2 millim., are bent in an obtuse angle, larger than in any 

 other Swedish species. Its apex is situated exactly on the median axis of the face. 

 The interstitial furrows are quite as large as the ridges or a little narrower. The ridges 

 near the apex of the shell are smooth or nearly so, higher up they are closely studded 

 by narrow, elongated, laterally compressed or sharply edged lamella3, ending in an 

 accuminated point upwards and placed in oblique rows on the ridges, their lower apex 

 turned against the median axis. The intervening furrows are quite smooth. On the 

 nucleus, where the shell has been destroyed, there is an impression of a median ridge, 

 nearly one millim. broad. It runs on the inside of the shell along the median axis of 

 each face, thus corresponding to the line which may be thought combining all the 

 apices of the angular ridges on the outside. It forms consequently a blunt, longitudinal 

 ridge on the interiör wall of the shell. Height 24 millim., diameter at the aperture 14 

 millim., diameter across the lower broken end 5 millim., diagonal line at the upper 

 aperture 14 millini., diagonal at the lower end 6 millim. Found only once in the 

 limestone strata b near Wisby. 



