Victorian Fossils, Part XVI. lOQ- 



Occurrence. — Silurian (Yeringiaii). In imulstone at Loyola, 

 near Mansfield; eoUected and presented by Mi-. (i. Sweet, F.G.JS. 

 Atrypa aspera also occurs in the Middle Devonian limestone of 

 Bindi, Gippsland, Victoria, specimens of Avhich. in the National 

 Miisfuni collection, Avere collected many years ago by Dr. A. W. 

 Howitt. 



Atrypa Jlinb I id.in sp. nov. Plate XI., Fig. 15. 



Description. — Shell, suborbicular, inflated. Brachial valve highly 

 convex in the median and cardinal regions, suddenly descending to- 

 a concave and outspread anterior margin, the edge of which is 

 ornamented with numerous outspread and irregularly disposed 

 spines. Surface of value with 4 or 5 strong, sharp, concentric 

 ridges, crossed by radial ribs, and forming nearly rectangular 

 interspaces which are conspicuously excavated. The marginal 

 spines, which are continuous with the radial ribs, are of variable 

 length and variously directed, this latter feature probably owing 

 to pressure. The type specimen is a well-preserved cast in which the 

 .shell seems to have been replaced by iron oxide. 



Measurements (Holotype). — Length of shell to bases of spines, 16 

 nnu. ; width, 18 mm. Length of longest spine about 7 mm. 



Observations. — This handsome species bears some relationship to- 

 two other forms of Atrypa, viz., A. hystrix, J, Hall.i and A. spinosa, 

 J. Hall. 2 In ^4. hystrix the ribs are folded into tubular spines, 

 mostly disposed round the margin of the shell, as in the present 

 species; but the radials are not sharply defined, leaving concave 

 areas in the interspaces between the concentrics and radials. 

 (»n the other hand, in A. spinosa the shell is beset all over with 

 spines, covering two-thirds of the total shell growth. Both A. hystrix 

 and A. spinosa occur in much higher horizons than the present 

 species; the former being found in the Chemung Group (Upper 

 Devonian). the second in the Hamilton Gi-oup (Middle Devonian), 

 r>f N. America. 



Occurrence. — Silurian (Yeringian). In mudstone; near Lily- 

 dale. Specimen collected and presented V)y \\. H. Annear, Esq. 



Fam. Spiriferidae. 



Genus CyPtina, Davidson. 



Cyrtina snti-tiipJicata. sp. nov. Plate XL, figs. \^a-c. 



Description. — Shell small, sub-triangular. Pedicle valve with a 

 high, triangular and arched cardinal area; remnants of the deltidial 



1 See Hall and Clarke, Pal. N. York, vol. viii., Crachiopoda, pt. ii., 1894, pi. h ., fljf. 23. 



2 See lidem, ibid., pi. Iv., figs. 21, 22. 



