336 Prof. J. Wood Mason on the Geographical 
margins of aperture tuberculate. Intercellular surface covered 
with finely tubercular ridges, whose terminations form the 
marginal denticles. Non-celluliferous aspect finely granu- 
lar, faintly striate. Cells encroach irregularly on this face 
(Plate IX. bcs, fig. 5); and small apertures (fig. 4) seem to 
represent aborted cells. 
Locality.—Gillfoot, Carluke ; Gair; Robroyston: in Upper 
Limestone shales. 
The ornament of a very young branch (fig. 6) has a curious 
resemblance to that of Sulcoret’pora. Figure 7 shows one of 
the apertures at the margin of the non-celluliferous aspect, 
and the wavy strie around it. 
The generic position of the fossil is uncertain. It is not a 
Polypora, since it is not reticulate. Thamniscus, King, shows 
a tendency to reticulation; but the junctions are at small angles. 
Synocladia presents the next step towards the Fenestella type. 
If the gemmuliferous vesicles described by King are essential 
to his Thamniscus, this character is wanting in our species, 
even in the best-preserved specimens. Longitudinal sections 
show the cells starting from an imaginary axis, and reaching 
the surface at various levels ; but the tendency to an arrange- 
ment in transverse series, seen in fig. 2, is apparent. We. 
have not yet found the base of attachment. Meanwhile, 
though strongly disposed to regard this fossil as a true 
Hornera or a member of a closely allied genus, we think it 
safer to leave it in the Paleozoic genus Thamniscus, and to 
name it Th.? Rankind, after the gentleman to whom we owe 
the finest examples. 
XLIUI.— Note on the Geographical Distribution of the 
Temnocephala chilensis of Blanchard. By James Woop 
Mason, Professor of Comparative Anatomy, Medical Col- 
lege, Calcutta. 
SomME months ago I received from Captain F. W. Hutton, 
Curator of the Otago Museum, Dunedin, New Zealand, a 
series of specimens of the freshwater crayfish lately described 
by him in this Journal under the name of Paranephrops 
setosus, and was astonished to find, in the sediment at the 
bottom of the jar containing these crustaceans, numerous ex- 
amples of this remarkable little Trematode (which owes its 
generic name to the fact that the cephalic end of its body is 
divided by four fissures into five tentacular processes, and 
