14 Fi'oceedivgs of the Royal Society of Victoria. 



species, apparently, has its branches diverging at an angle of about 

 40° and quite sti'aight, measuring, in one instance, more than 5mm. 

 in length. In some places the slabs are crowded with a great 

 number of young examples of the same genus, showing the sicula 

 and three spines very clearly at times, but in no case is the 

 outline of the hydrothecas visible. 



The only other forms present are DiiDlograptidaj. Only one of 

 these am I able to determine sj^ecitically. This is Diplograptiis 

 foliaceus, Murch. About half a dozen specimens occur. The 

 hydrophyton is about one-and-a-half inches long and one-eighth 

 inch broad, parallel sided for the greater part of its length and 

 gradually tapering towards the proximal end, which is imperfect 

 in all the specimens. The virgula is not visible. Hydrotheca^ 

 about twenty-five to the inch, and having the form shown by 

 Hopkinson and Lapworth in two of their figures.^ 



There are two other species of Diplographis which I am unable 

 to determine with certainty. 



The family Dicranograptidaj to which Dicellograptus belongs 

 is, according to Lapworth, confined to the Upper Ordovician." 

 Diplograptiis foliaceus, though not having exactly the same range, 

 is associated with Dicranograptidte in Britain, and I have identi- 

 fied the same species as occurring rarely at Darriwill. The beds 

 at the latter place I previously placed tentatively on the horizon 

 of the Loganograptus zone at Castlemaine.'^ Since then Mr. 

 Pritchard and myself have paid two visits to Wilkinson's locality 

 at Darriwill,'^ and from an examination of the fauna I am 

 inclined to refer it to a slightly higher position than I did 

 previously, though Dicranograptidje have not been observed. 



The only other fossil recorded from Mount Matlock is Cardmm 

 gippslnndiaan, M'Coy. This is also recorded from Russell's Creek, 

 Gippsland, by Sir Frederick M'Coy, in association with Orthoceras 

 striato-piinctaium, Miinst.* This association induces Sir Frederick 

 to refer the beds containing the Cardiuvi to the (Upper) Silurian. 



The occurrence of Ordovician fossils at Matlock is consequently 

 of considerable interest and indicates the presence of an inlier in 



1 Q.J.G.S. xxxi., 1875, pi. xxxv., figs. 7e, Ig. 



2 A.M.N.H. 5, vi., 1880, p. 21. 



3 Proc. Roy. Soc. Vic, viii. (N.S.), 1S94, p. 76. 

 1 W.L.S., 1, of Quarter Sheet 19, S.W. 



5 Geol. Surv. Vict., Progress Report, vi., 1880, p. 71. 



