CONULARIA QTJADRISULCATA. 25 



defined ; edges sharp and base rounded. Facial grooves deep, straight, central. 

 Aperture unknown; apex sharply pointed; apical septa unknown. Ornamentation 

 only seen under microscope. Ridges very fine and closely tubercnlated (250 — 300 

 in 5 mm.), forming an angle of 145° — 150° along the facial grooves, ceasing 

 abruptly at the marginal grooves. Growth-lines following the same course as the 

 ridges, and visible to the naked eye. 



Dimensions. — Length, 20 — 30 mm. Greatest width of one face, 5 mm. 



Description. — -This small shell appears perfectly smooth when seen with the 

 naked eye, but under high magnification the very fine, and often well preserved, 

 ornamentation is well seen (PI. II, fig. 9). The vertical striation, seen on the 

 ridges, does not appear to extend to the furrows. The marginal and central 

 grooves are quite smooth. 



Affinities. — Some specimens of this shell might be mistaken for the smoother 

 examples of G. linnarssoni, but under the microscope the ornamentation distin- 

 guishes it from that and all other forms. It is probably allied to G. coronata. 



Horizon and Locality. — Wenlock Shale : Buildwas. 



Type. — Museum of Practical Geology (reg. no. 12028). 



Conularia sp. Plate II, fig. 10. 



Diagnosis. — Shell small, tapering uniformly; cross- section square. Faces 

 equal, flat; apical angle 15°. Marginal grooves well defined, rounded, fairly deep. 

 Facial grooves central, fine. Aperture, apex, and apical septa unknown. 

 Ornamentation inconspicuous; ridges fine and close (25 in 5 mm.) forming an 

 angle of 130° along the facial groove. Ridges nearly as wide as the furrows; 

 tubercnlated ; furrows smooth. 



Dimensions. — Length, 25 mm. ? Width of face, 7 mm. 



Description. — There is only one example of this small form, and as the 

 preservation is not very good, and only one complete face is seen, I have not named 

 it as a separate species. The most marked characters are the square cross-section, 

 rounded marginal grooves (PI. II, fig. 10 t>), and fine ridges symmetrically disposed 

 along the facial grooves. The finer ornamentation is almost obliterated, but the 

 ridges appear to be tuberculated (PI. II, fig. 10 c). 



Affinities. — This species is nearly allied to C. microscopica, from which it is 

 distinguished by the much coarser ornamentation. 



Horizon and Locality. — Wenlock Limestone : Ledbury. 



Type.— British Museum (Nat. Hist.) (reg. no. G. 117U8). 



Conularia quadrisulcata, Sowerby. Plate III, figs. 2 — 6. 



1821. Conularia quadrisulcata, Sowerby, Miu. Couch., vol. iii, p. 107, pi. 260, figs. 5, 6. 

 1840. Conularia quadrisulcata, J. Prestwich, Tnuis. Greol. Soc. [2], vol. v, p. 442, pi. xl, fig. 2. 



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