Victorian Fossils, Part XIX. 93^ 



fig. 20. Salter, 1867, Siluria, Ed. 4, p. 531, pi. XXV., fig. 3. 



Oriostoma glohosum, Schl. sp., Lindstrom, 1884. Kongl. Svenska 

 Vet.-Akad. Handl. Bd. XIX., No. 6, p. 160, pi. XVII., figs. 24, 25, 

 29-31; pi. XVIII., fig. 24; pi. XX., fig. 16. 



Observations. — The representatives in Victoria of this widely 

 distributed species are rare and small. They are clearly referable 

 to the above form on account of the depressed spire, vetitricose 

 whorls and expanding mouth. The ornament, as in the European 

 species, consists of numerous spiral keels, about ten on the body 

 whorl, with an intermediate and finer line. The interspaces are 

 crossed by fine and coarse lines rather closely set and slightly 

 curved. 



Dimensions. — Greatest diameter of plesiotype, 11 mm.; height, 

 9 mm. Width of aperture, 7 mm. 



Occtirrence. — Silurian (Yeringian). In limestone. Cave Hill, 

 Lilydale. Collected by the Rev. A. W. Cresswell, M.A. Also a fine 

 example presented by Mr. J. S. Green. 



Fani. Trochidae. 

 Genus Scalaetrochus, Etheridge, jnr. 



Scalaetrochus antiquus, Cresswell sp. 



Stomatia aiitiqua, Cresswell, 1893. Proc. R. Soc. Vict., voL 

 V. (N.S.)., pp. 41, 43, pi. VIII., fig. 3. 



Trochus (Scalaetrochus) antiquus, Cressw. sp.. Chapman, 1913.. 

 Rep. Aust. Assoc. Adv. Sci., vol. XIV., p. 229. 



Observations. — Some of the Victorian examples of Scalaetrochus 

 appear to indicate the presence of a narrow umbilicus, l and there- 

 fore show affinity to Omjohalotrochus. 



The above species was founded on a fragmentary shell, which is- 

 closely comparable with Etheridge' s Trochus {Scalaetrochus) lind-- 

 stroeini.'^ It differs in the slightly convex surface of the volutions, 

 whereas in Etheridge's species they are either flat or concave. 



A specimen figured by Lindstrom from the Silurian of Gotland^- 

 as Trochus gotlandicus shows some affinity with the above, and also' 

 with Sc. lindstroemi, but it is non-perf orate. 



De Koninck's Euom/phalns {Omj^halotrochvs) clarkei'^ is closely 

 related to .S'. antiqutis, and differs only in the stronger and more- 

 irregular growth of the shell. 



1 Rec. Austr. Mus., vol. i., No. 3, 1890, p. 66. 



2 Ibid., p. 66, pi. viii., figs. 1, 2. 



3 Konsl. Svenska Vet.-Akad. Handl., Bd. .xiv., No. 6, 1884, p. 146, pi. xiv., figs. 1-11. 



4 Mem. Geol. Surv. N. S. Wales, Pal. No. 6, 1898, p. 32, pi. i., fig. 7. 



