106 Frederick Chapinan: 



Its occin'reiico in Victoria is iiitorestiii'j, as it seems ronfiiied 

 to the Melbouniiau sta^e of tlie Sihii'ian rocks. 



OccuJ'reiice. — Silurian (Melbournian). Heathcote. From th© 

 (^eol. Surv. Coll. Bb oO " Kanges E. of Heathcote," and Bb 51 " Mt. 

 Ida, N. of Heathcote." 



(Jenus CiOPinda, Barrande. 

 Clnrindd Vni<in\fcra, Sow. sp., var. iriIkiii>>oin , Eth. fil. 



PentamernH liiif/iiifer. J. de C. Sinverbv, Etheridge, R., jnr., 

 1892, Records Geol. Surv.. N. S. Wales, vol. iii., pt. 2, p. 52, pi. xi., 

 figs. 5-9. 



Observations. — Two specimens, rather crushed, but still showing 

 the characters of the above variety, were collected by the early 

 Geological Survey of Victoria from " sect. xii. Parish of Taring, " 

 a locality west of the present Yering railway station. The specimens 

 were tableted and labelled " Pentcnnerns " by Sir F. McCoy. 



The variety wilhinsoni differs from the specific form, according 

 to Mr. Etheridge. 1 " in its peculiarly flattened ventral sulcus, and 

 otlier minor characters. As before said, it seems to occupy an inter- 

 mediate position between F. linr/vifer and P. globosus." 



Both Victorian specimens are ventral valves, and, although 

 deformed by pressure, the anterior margin is sufficiently (distinct to 

 show the broad ventral sulcus mentioned by Etheridge as a character 

 of his N. S. Wales variety. This variety occurs in N. S. Wales in 

 the Bowning Series (the Lower Limestones and the Lower Trilobite 

 Bed), and in the Silurian of Hatton's Corner, Yass. 



Occurrence. — Silurian (Yeringian). Geol. Surv. Coll. Sect, xii.. 

 Parish of Yering (W. of Yering railway station). 



Genus Gypidula, J. Hall. 



Gypidnlii ricforiae, sp. nov. Plate XT., fig. 12. 



Description. — Shell sub-pentagonal or broadly ovate. Ventral 

 valve very tumid, with the beak strongly incurved; mesial fold 

 broad, elevated, commencing about one-third from the beak and 

 extending to the anterior margin, and medially sulcated. Biachial 

 valve almost fiat or gently convex in the median area, curving back- 

 wards towards the anterior margin; with a broad mesial sinus 

 bearing a distinct median plait extending from the hinge to the 

 anterior margin. Numerous concentric growth-lines on both valves. 



1 Loc. cit., p. 33. 



