European Ferns. 
184 
OPHIOGLOSSUM LUSITANICUM. L. 
This diminutive species is of wide distribution. It can hardly be considered a British plant, 
in the strict sense of the term, although it is found in Jersey, where it was discovered in 1854, and 
was quite recently discovered in Ireland, upon Horn Head in north-western Donegal. It is a 
common plant in the Mediterranean region, and is found in Algeria and Morocco, as well as in 
the Atlantic Islands — the Azores, the Canaries, Madeira, and the Cape Verde Islands. Mr. Baker 
includes under this species O. gramineum, Willd., from northern and peninsular India, as well as 
another plant, called O. gramineum by Brown, from New Zealand and Australia, and “ three 
closely-allied forms gathered by Dr. Welwitsch in Angola.” But he retains it as distinct from O. 
vulgatum, with which, however, some authors unite it. 
Ophioglossum lusitanicum is readily distinguished from the common Adder’s-tongue by its 
very small size, the whole plant being rarely more than three inches in height, and sometimes 
scarcely attaining one inch. The barren portion of the frond is much narrower than in O. vul- 
gatum , tapering gradually to the base, and it also differs, as will be seen from our figure, in the 
reticulation, which is much less branched ; the texture, too, is thicker. A minute character by 
which the two species may be distinguished is to be found in the spores, which are tuberculated in 
O. vulgatum, but smooth in O. lusitanicum. The fronds are produced in the autumn, remaining 
throughout the winter, and dying down in the spring. So small a plant is, of course, likely to be 
overlooked, and it is probable that a close search for it in some of the south-western districts of 
England might be rewarded by its discovery. 
