Natural History of Victoria. 139 
Museum from our strata, although a rarer species than the 
others. The forms called D. folium and D. bicornis in Europe 
also occur. Of the short leaf-shaped Graptolites allied to the 
D. folium of Hisinger and D. ovatus of Barrande from those 
ancient beds in Sweden and Bohemia, for which Professor Hall 
has recently founded the subgenus Phyllograptus, I can ideutify 
in the utmost profusion in several localities north of Melbourne 
his typical species P. typus, which he describes as so abundant 
in the similar slates of Canada, in the Decades of the Palzeonto- 
logy prepared by him to illustrate this portion of Sir W. Logan’s 
‘Geological Survey of Canada;’ and it occurs in Victoria in all 
the extremes of varied form which he describes it to assume 
in America; several of the specimens, I might add, prove 
clearly the fact of which he seemed to have some doubt when he 
first announced it, and which was generally rejected by European 
geologists—namely, the quadripartite arrangement of the cell- 
lamine. Of the Twin Graptolites, for which I formerly proposed 
the genus Didymograpsus (also characteristic of strata below the 
Upper Silurian), we have in Victoria the D. serratulus (Hall) 
identical with that from the New York slates; the D. caduceus 
(Salter), identical with his Quebec examples, is very common ; 
and the D. furcatus (Hall), identical with the New York “ Utica 
slate” species, also occurs, though more rarely. Also we have 
that compound species, the Graptolites gracilis (Hall), exactly 
identical with the New York and Canada forms, and, more curious 
still, many of those extraordinary compound radiating forms, 
the Graptolites Logani (Hall), G. quadribrachiatus, and G. octo- 
brachiatus (Hall), so recently discovered in abundance in Canada, 
and peculiar to that country, except for the present announce- 
ment of their occurring in Victoria, in the slates at Castlemaine. 
Of the simple, or doubtfully twin, Graptolites, I have also deter- 
mined the Graptolites Ludensis (Murch.), G. tenuis (Portlock), 
G. latus (M‘Coy), and G. sagittarius (Hisinger), occurring in 
various localities within a hundred miles north of Melbourne in 
abundance of well-preserved specimens identical in every respect 
with specimens of the same species occurring in the similar 
slates in Wales, Scotland, and Ireland. In Victoria, as in most 
of the European and American Graptolite localities, the slates 
containing abundance of these bodies frequently contain no 
organic remains of Mollusca; one of the exceptions to this rule 
occurs in the black Graptolite slate of Pen Cerrig, near Builth, 
in Radnorshire, where, with the Graptolites D. mucronatus and 
D. pristis, I discovered in 1851 an immense profusion of a small 
Brachiopod shell, which I published under the name of Siphono- 
treta micula. Kuropean geoiogists in general will, I have no 
doubt, be as much astonished as I was to recognize exactly the 
