SCOLOPENDRIUM. 
E have here a small and very distinct genus, even if we understand it in 
the extended form proposed by Sir William J. Hooker, who includes in it 
the curious “ Walking Fern,” usually known as Camptosorus rhizophyllus, to 
which we referred at p. 65, where a figure of the plant will be found. 
Even on this estimate it contains only nine species, but these are widely 
distributed, so that the genus is represented in most parts of the globe. 
Besides the two European species, which we shall have to describe more 
at length, there is an eastern one, S', pinnatum , from the Philippines, 
which has large fronds from two to four feet long, which, as the name 
implies, are often (though not always) pinnate, with an entire terminal pinna, 
and from one to six pairs of lateral ones. Two are Brazilian, one, S. 
Douglasii , being a beautiful plant with fronds sometimes ten inches long and nearly 
half as broad, sometimes much resembling a large poplar leaf ; one is a native of Ualan 
and another of Mexico, and the two species of Camptosorus (see p. 65) belong one to 
Kamtschatka and the other to the United States. 
With the exception of S. Hemionitis , one of the two European species, which has 
lately been found in Algieis, the genus is not represented on the continent of Africa, 
while in Asia no species is recorded from India or China. 
THE HART’S-TONGUE : SCOLOPENDRIUM VULGARE, Sym. 
The common Hart’s-tongue, although more abundant in some districts than in others, 
is one of the most generally distributed of British ferns ; it is also one of the most 
variable, although in all its forms it is easily recognised. It is found in a variety of 
habitats, preferring those where it is exposed to abundance of moisture : thus it is often 
found fringing the mouth of an old well, its cool, green fronds hanging down for some 
distance. Occasionally, however, it chooses a very opposite situation, and small, stunted plants 
may be found in the cracks of an old stone-wall, seeming far from comfortable in their 
restricted abode. It is one of the easiest of ferns to cultivate, requiring no attention, and 
soon becoming an object of much beauty. The roots are black and long, and the rhizome 
is roundish, tufted, and sub-erect ; the fronds are very variable in shape and size, but in 
a normal state are from a foot to a foot and a half in length, distinctly heart-shaped at 
the base, tapering into a point at the apex : when they first unroll in April or May they 
are of a bright light-green, and quite erect, but when quite uncurled they gradually 
assume a horizontal position, and ultimately hang down, if in a situation where this is 
possible. The venation of the fronds is very characteristic : from the prominent rachis or 
midrib, which runs down the centre of the frond, forked veins proceed, which are again divided 
into venules, and these are once or twice forked. The development of the sori is worth 
notice : in the mature plant they appear in the form of dark-brown lines on the back of the 
frond, and each line seems, at first sight, to consist of one sorus only ; but closer examina- 
tion and some attention to the growth of the plant shows that each line is really composed 
of two rows of sori, one row being attached to the outermost venules of each vein. The 
