130 BRITISH MARINE ALG. 
narrower, lanceolate, or pointed at the tips, and of a much lighter colour, 
being of a pale rose or delicate pink. The fronds of this species are 
tufted and originate in a single lanceolate leaf, having a distinctly marked 
midrib, from which it throws out other similar leaves, and from these are 
produced others, which in turn bear another series; and in this manner 
the primary leaf-like frond becomes clothed with leaves of various lengths, 
which spread out in the water, and give a somewhat circular outline to 
the plant. Coccidia are produced on the midrib, as represented in our 
illustration ; tetraspores are disposed in long narrow lines on each side 
of the midrib, near the tips of the leaves. Barren specimens are generally 
the most luxuriant, those in fruit being much narrower, and of a paler 
colour. This beautiful species is annual. It grows in shady rock pools 
and on the stems of the Laminaria. It is rare in Scotland, but tolerably 
abundant on the south coast of Devon, and particularly fine at Plymouth, 
and at Bantry Bay, in Ireland. 
Very nearly related to Delesseria is the genus Nitophyllum, a tribe of 
membranaceous plants, which are distinguished chiefly by their more or less 
broad lobes, rather than leaves or branches. None of these plants are 
furnished with a midrib, though some species have tolerably distinct veins, 
very strongly marked at the base, but vanishing gradually as they ascend 
into the upper divisions of the plants. Most of the species in drying have 
a fine polished shining surface, whence the generic name of Nitophyllum, or 
shining leaf. The fine species, Nitophyllum Hillie (Fig. 119) was named 
by Dr. Greville in honour of Miss Hill, who discovered it. The plant 
arises from a small disc-like root, and rapidly expands into a roundish or 
fan-shaped frond, from 8 inches to 20 inches in circumference, which is 
cleft all round its margin into irregularly shaped lobes of large size. Veins, 
more or less waved, arise from the base, and sometimes spread over the 
surface of the frond. Globular tubercles containing spores are scattered 
over the whole of the plant. Tetraspores are produced in the upper part of 
the lobes, and being very minute, appear like little granular spots. The 
colour is a fine rose red, which it preserves in drying. N. Bonnemaison is 
very rare, though found on all the British shores. It grows on the stems 
of Laminaria digitata (Fig. 46). The fronds are seldom more than 4in. long, 
the segments are deeply cleft, and are about as broad as long. The 
tubercles are smaller than those in N. Hilliw, but the groups of tetraspores 
are larger. The substance is much more delicate than that of the fore- 
going species, and the colour is a beautiful rose pink. N. Gmelini is 
another somewhat rare species. I have found it at Hastings, though 
once only; but at Plymouth it is generally abundant and sometimes of 
large size. The fronds are more or less deeply cleft, some specimens being 
even jagged at the margin, others having beautifully rounded lobes, and 
occasionally some are divided into long ribbon-like segments, while all 
have. a distinctly rounded outline. The colour is a deep “red, often 
inclining to a brownish purple. Tubercles are scattered over the surface 
of the frond, but the tetraspores are invariably produced in groups just 
