38 
dictyodromic*, and corresponds very well with the similarly designated 
venation of Salix fragilis, S. alba, S. purpurea, and other species of this 
genus. I have no hesitation, therefore, in referring these leaf fossils, which 
were collected by Dr. It. MacCormick, Naval Surgeon of the Antarctic Ex- 
pedition of the vessels “ Erebus” and “Terror,” to Salix. As regards hitherto 
described European Tertiary plants, our species approaches most closely the 
S. varians, Goepp., which occurs also in the Tertiary Elora of the Arctic Zone. 
In the North American Tertiary Elora only entire-leaved willows have, so far, 
been discovered, among which the S. tabellaris, Lesq.,f is in some measure 
analogous to S. Cormickii. 
Locality and Horizon. — Near Ilobart, Tasmania; in yellow Travertin 
of Upper Tertiary Age. 
Collection. — British Museum (Natural History Branch). 
MORE./L. 
Genus — FICONIUM. 
Gen. Char. — Ncrvatione camptodroma; nervis secundariis duplicis 
generis, lirmis ct tenuissimis, firmis subangulis 45-50° orientibus prominen- 
tibus ; nervos secundarios tenuissimos plures, includentibus. 
Eiconium Solandri, sp. nov. 
Plate III, Fig. 4. 
Sp. Char. — E. foliis coriaceis ovato-lanccolatis, basi acutis, apicc acn- 
minatis, margine integerrimis ; nervo primario valido prominente recto, 
* Many years ago the term “ dictyodromic variation'” (netzlaufige Nervation), which I have introduced into 
phyto-paleeontological science, was objected to as unsuitable and useless. The objection was grounded on the 
fact that there are cases in which dictyodromic venation cannot be distinguished from camptodromic venation. 
Now, 1 myself was the first to observe that dictyodromic venation merges into the camptodromic. Even the 
craspedodromic form of venation, to which no exception has been taken, merges into the camptodromic form 
( < in Querent). These forms of venation are simply links in a series of properties, just as the hexahedron, the 
octahedron, the rhombic-dodecahedron, &c., are members of the tesseral [or cubic] system of crystals, and may all 
enter into combination. Yet it does not appear to have occurred to anybody that these terms are of no use in 
crystallography. 1 have not deemed it worth my while to take any notice of such trifling objections. But as it 
appears that lately I have been again accused from the same quarter of introducing useless distinguishing 
characters into the study of the venation of leaves for phyto-palseontological purposes, I think it advisable to 
take this opportunity of saving the term dictyodromic (“ netzliiufig ”), which is the one especially objected to, 
from annihilation. I may add that I use the term with advantage only when the secondary veins of a leaf are 
gently flexuose from their origin, and in their further course merge into the leaf net. This peculiarity is a very 
striking one, and a leaf possessing it — for example, the Zenobia Jloribunda (Ettingshausen, Blattskelete 
der Dicotyledonen, PI. XXXVIII, figs. 5, 0) — is remarkably different from one with camptodromic venation ; 
for example, the Fornteronia difformix (Ettingshausen, loc. ait,., PI. XXVIII, fig. 1). The two examples adduced 
are of nearly the same form and size. 
+ L. Lesquereux, “ On Species of Fossil Plants from the Tertiary of the State of Mississippi.” Trans. Am. 
Phil. Soc . , vol. xiii, p. 414, PI. XVII, fig. 4. 
