148 Scventifie Intelligence. 
the Gymnosperms. The Calamites, according to Dr. Dawson, are 
face of the stems. . But other fossils marked externally like Cala- 
: : ‘ jong 
Calamodendron. The Calamoden often have a considerable 
thickness of woody sg about the pee? jointed internal 
axis, consisting of woody tissue in wedges separated by interven 
ing tracts of eilgiant tissue (medullary rays according to William- 
son); and they are therefore classed by Dr. Dawson with Gymnos- 
perms. 
Padi makes the line from Sigillaria to Lepidodendron to 
order, Lepido ees. Syringodendron, Clathraria, 
Seek Rhytidolepis ; y and the line from Sigi illaria to Equi- 
setum to in — er Calamopitus (of Williamson), 
Bornia, Calami 
6. Le piedene and Sigillarie.—In a paper read before the 
Royal Society, June 15, Blinc W. C. Wi. LIAMSON es the 
structure of specimens of. nd appears to 
make good the conclusion ri it has an imperfect exogenous struc- 
ture. He observes that it has a a — a axis, which is 
vessels, but of smaller size, and arran me vertical radiatin g lami 
which are separated by short vertical piles of cells believed 2 
be medullary rays. In a transverse s section the intersected mouths 
of the vessels form radiating lines,” and the structure is pro 
nounced an early type of an exogenous cylinder. rom 
ae alone the vascular bundles going to the leaves are given 
He describes Stigmaria (“ well-known,” he says, “ to be a root 
of Sigillaria,”) as having “a cellular pith without any trace of a 
two distinct sets o rimary and secon ars medullar rays.” 
Other facts stated tend to show that these plants are of the Lepr 
dodendroid type, and Prof. Williamson therefore includes t 
Lepidodendroid and Sigillarian plants in acommon family, making 
them, along with the Calamitee, to constitute an Zeogenous divr 
sion of the vascular Cryptogams, while the Ferns belong to > 
Endogenous division, “the former uniting “the ee with 
the Exogens, through the Cycadex and other Gymn ; and 
of He sdererg corals in Littleton, N. H. New ampshire 
of a peauieis character. Professors H. D. and W. B. Rogers sup- 
Kroon at one time they had found Silurian fossils in the 
ountain Notch, but afterward withdrew the opinion. 
