EQUISETUM. 
211 
upon them black and numerous, and the spores pale- 
coloured. 
A section of the stem exhibits a smooth outline on 
the exterior, a very large central hollow, and two rows 
of openings, the outer oval, 
the inner circular and very 
small. 
This is one of the only spe- 
cies of use as food for cattle. 
Linnaeus says that it is cut 
up and given to cows in Swe- 
den, and that it makes the 
milk plentiful ; in Lapland the 
reindeer eat it greedily, and 
the people would do well to 
cultivate it. Mr. Knapp gives 
an account of a colony of 
short-tailed water-rats who 
subsisted upon this plant, and as they fed upon the hard 
caudex the sound of their gnawing was heard at a con- 
siderable distance. 
The Smooth Naked Horsetail is a common object in 
wet marshy grounds throughout Great Britain, often 
mingling amongst the Marsh Marigold and other water- 
plants. It also prevails throughout Europe and North 
America, and wherever the climate is cold or temperate. 
63. Eqmsetum palustre, Linn. Marsh Horsetail. 
Candex black, extensively creeping, and glossy. Boots slen- 
der, and repeatedly divided. Stem erect, 1 \ feet high, furrowed 
four to eight times, and bearing whorls of branches. Sheaths 
toothed. Cones long and narrow. 
The Marsh Horsetail has roughish stems and loose 
p 2 
