EQUISETUM. 
265 
and the cylinder of the stem is furnished only with a row 
of minute cavities near the inner margin ; this cylinder is 
very thin compared with the diameter of the stem, the 
central cavity being unusually large. The present plant, 
therefore, though it has been considered a variety of E. 
palustrey is most strikingly distinct from that species in 
the structure of its stem. 
The fructification is produced only by a portion of the 
branches. The cones are ovate, obtuse, and very fre- 
quently sessile in the uppermost sheath. The scales are 
black, exceeding a hundred in number ; the spore-cases 
are pale-coloured. Usually only the termination of the 
central stem bears fructification, but it sometimes happens, 
though rarely, that some of the uppermost branches are 
also fertile. 
This plant is the most fodder-like of any of the Equi- 
setums^ owing to its less flinty cuticle, but in this point of 
view it is, at least in this country, of very small import- 
ance. It is, however, stated to be used in Sweden as food 
for cattle, in order that the cows may give more milk 
and in Lapland, it is, even when dry, eaten with avidity 
by the reindeer, though they will not touch common hay. 
Linnaeus censures the improvidence of the Laplanders in 
