New or Little-knoion Victorian Fossils. 301 



Primitia subtrigonalis, sp. nov. (PI. XTIL, Figs. la-c). 



Description. — Carapace convex, margins blunt ; lateral out- 

 line subtrigonal with evenly rounded dorsal angles ; anterior 

 end somewhat produced, posterior broadly rounded. Sub-cen- 

 tral pit rather con'spicuous and circular. Edge view elongate- 

 ovate, slightlj'' more compressed anteriorly. End view regu- 

 larly ovate. Edges of valves thickened, especially the dorsal 

 and ventral borders of the left, giving an appearance of over- 

 lapping. Surface of valves finely punctate. 



Dimensions. — ^Length of carapace, .7 mm. ; height, .5 mm. ; 

 thickness, .3 mm. 



Affinities. — The above species seems to approach most nearly 

 in outline P. trigonalis, Jones and HoU,^ from the Wenlock 

 Limestone, but it differs in the more elongate form of the 

 carapace, the bkmter edges of the valves and in having a well- 

 marked sub-central depression. 



Locality and Horizon. — Cave Hill. Lilydale. Silurian (Yerin- 

 gia.n). 



Primitia punctata, Jones. (PI. XIII., Figs. 2a-c). 



Primitia punctata, Jones, 1887. Ann. Mag. Nat. Hist., ser. 

 5, vol. xix., p. 193, pi. vii., figs. 9 a, b. 



Observations. — The long-oblong carapace with its strongly 

 convex sides, the usually faint mid-dorsal sulcus and the 

 punctate surfaces of the valves confirms the relationship of our 

 examples with the above species. 



P. punctata was originally described from the shales over 

 the Wenlock Limestone of Sliropshire, England, and I have 

 since recorded it from the Silurian (Wenlockian) of Mulde, 

 Gothland.^ 



Locality and Horizon. — Cave Hill, Lilydale. Silurian (Yerin- 

 gian). 



Primitia semicultrata, sp. nov. (PI. XIII., Figs. 4a-c). 



Description. — Carapace seen from the side, oblong and strong- 

 ly convex. Dorsal edge straight, ventral nearly so, but slightly 



1 Ann. Mag. Nat. Hist., ser. 3, vol. xvi., 1865, p. 421, pi. xiii., figs. 4a, b. 



2 Ann. Mag. Nat. Hist., ser. 7, vol. vii., 1901, p. 148. 



