THE FERNS OF NORTH-WESTERN INDIA . 
201 
I cannot see much, if any, resemblance of this fern fco A. Prescottianum 
Hook ; though Mr. Clarke says the two species are no doubt very close, and 
Colonel Beddome that A. Thomsoni is very near the smaller forms of A, Pres - 
eottiamm , and that it is very probable that they are only varieties of the 
same plant (name not stated). A. Prescottianum is a comparatively large fem, 
and grows to dense bushy thickets ; it is very scaly all over, shaggy almost. 
A. Thomsoni is a small plant, growing on rocks, or on rocky ground in forest, 
but each plant separately, so far as I have seen. The largest plants of A. 
Thomsoni I have seen are Mr. Collan’s from Nag Tiba Mi in Tehri Garhwal, 
one frond of which is 17£X H ins., and it is just as much A. Thomsoni as is 
the smallest of all those cited above. But there is difference between some of 
these : McDonelTs from the Bach Pass in Ohamba and Duthie’s No. 101 from 
the Ganges Yy. have stipes and rhachis almost glabrous, and quite a different 
cutting of frond from that of most others— like some one's var. alpina of A* 
Prescottianum from Sikkim ; and some at least of the soil of Duthie*s plant are 
nephrodioid. These cannot, however, be Clarke’s var. gracilis (Lastrea gracilis 
Moore), for that is said to have fronds smaller than those of typical A, Thom » 
soni, whereas Buthie’s is a large plant with fronds 10 ins. long by ins. 
broad. Another form has broadly falcate and auricled pinnae with sharp teeth, 
much cut away at the base on the lower side ; while another has straight, 
almost dimidiate pinnae, and segments spreading on both sides ; bnt these are 
intermediate forms, and the habit of all is alike. 
[ A . aculeatum Sw. is attributed in all the books to the Indian 
Region. The Synopsis says— {g Hab.-~Throm Uout the world ; but 
gives as a synonym A. squarrosum Don {rufo-harbatum Wall.), wb’jh 
6i has the rachis densely clothed with reddish-brown Abrillose scales, 
and we are left in doubt under which of the three varieties it recognises, 
namely « A. Ubatum , Sw., 3. A. aculeatum, Sw. and 7 A. angulare 
Wiiid,, A . squarrosum ought to be placed. From the fact that var. 
3 is given in the Synopsis as a variety of A . aculeatum Sw., i.e., as 
a variety of itself, I gather that the species 18, A . aculeatum Sw., of 
the Synopsis m a theoretical conception of the authors* ; but it ought 
to have been given a distinctive specific name, instead of being 
fathered on Swartz, and I would suggest metaphysica , hypothetical or 
thmetrn , or some equivalent name, to indicate that the plant has no 
existence in nature, Swartz did not include A . lobatum under A . 
aculeatum, but pm it m a ieparate species, with only " Anglia 95 m 
the habitat. 
Mr. Clarke says A. aculeatum Sw, (var 3 of the Synopsis) is very 
common in the Himalaya and Khasia, alt. 2,000'— 13,000'; and he 
