ON THE FOSSIL PHTLLOPODA OF THE PALEOZOIC EOCKS. 61 



of its upper moiety (obscured at the top), becoming narrow lower down. 

 A slight groove on each side is also present. No delicate ridging is seen, 

 nor any pits for bases of prickles. The stylets are smooth, and apparently 

 subtriangnlar in section, each bearing one strong ridge on the upper part 

 of the under face (as exposed). 



In these features this form differs from C. Bohemwa,^ Barrande, the 

 telson of which is not deeply furrowed on its ventral (under) face ; and 

 the latter species has longer stylets, oval in section, and neatly ridged 

 throughout. 



The Scandinavian specimen occurs, as an impression, in hard black 

 shale ('Brachiopod-Skiffer') from the Lower- Silurian (Upper-Caradoc) 

 of Westergotland (Westrogothia), a province in the western part of the 

 mainland of Sweden. It has been badly figured in Angelin's unpublished 

 ' Tab. LIIL' (figs. 18 and 19). 



All the following are from the Upper- Silurian : — 



2. G. Bohemica, Barr. — Portions of the shafts of straight, strong styles 

 (telsons), similar to that of C. Bohemica, and chiefly from the middle 

 and lower parts of the styles. In section these Scandinavian specimens 

 are not so oblong as in Barrande's figs. 7 and 9 (pi. 19, ' Syst. Sil. 

 Boheme,' vol. i. Suppl.), and the ridging on the lower face is somewhat 

 stronger. (One piece=fig. 5 of Angelin's unpublished Table B.) 



From the cream-coloured limestone (Wenlock Shale) of Eksta, Goth- 

 land. 



3. A piece of telson of the same kind as the above. Shown by a 

 drawing from Stockholm. From the ("Wenlock Shale) Sandstone of 

 Bursvik, South Gothland. 



4. C. Bohemica, Barr., var. ? — A fragment of strong thick telson in 

 cream-coloured limestone, differing from G. Bohemica : (1) in being curved 

 (the convexity being dorsal, on the upper surface), (2) in having the 

 two pitted ridges lower down on the side, and (3) in the under surface 

 being more strongly ridged than in G. Bohemica. In some respects it 

 approaches C. valida, J. and W. In whitish limestone with Strophomena, 

 Trilobites, Tentaculites, Encrinites, &c. (Wenlock Limestone), from 

 Rone, Gothland. 



5. G. Bohemica, var. ? — A small fragment from Lau, Gothland, in 

 cream- coloured fossiliferous limestone (Wenlock). It tapers rather rapidly, 

 bears several thin ridges, and is oval in section. It may be a part of a 

 stylet of some variety of G. Bohemica, for that species has its stylets 

 ridged throughout. 



6. Geratiocaris, sp. nov. ? — A fragment of a style or a stylet. It is 

 somewhat like the last (5), but the ridges are fewer, broader, and 

 rounded. This is a drawing sent from Stockholm. The specimen 

 (Mus. Geol. Survey, Sweden) was from Frojel, Gothland (Wenlock 

 Shale). 



7. Geratiocaris concinna, sp. nov. — A small portion of a straight, rapidly 

 tapering style, convex on the upper, and concave along the lower face, with 

 a half-moon-shaped section in the upper, and more oblong in the lower 

 part. Two rows of small pits along the back, one on each side of the raised 

 middle. The test is of a dull, light chesnut tint ; it is hollow and filled 

 with limestone. From Frojel, Gothland. This tapering telson (7 mm. 

 broad at the top, and 4^ mm. at the end of the fragment 15 mm. long) 



' Sijst. Sil Boheme, vol. i. Supplement, p. 447, pi. 19, figs. 1-13. 



