MR: C. B. CLARKE. ON THE FERNS OF NORTHERN INDIA. 581 
| Var. pseud-undulata.. Midrib of the fertile pinnæ without sori in the fully ripe fruit. 
Khasia, Griffith; a solitary example, having exactly the venation of the North-Indian 
A. erispatulum type, and not that of the Tenasserim true A. undulatum, Wall. Cat. 140; 
see Bedd. Ferns Brit. Ind. t. 115. 
ll. A. virens, Wall. Cat. 1033. Barren pinn:e usually 9-15, 6 by 14 in., slightly serrate, 
green, a series of costal arches without included veins along their midribs; primary 
lateral veins distinct, parallel, intermediate secondary veins anastomosing freely, 
with included: free veinlets ; fertile pinnæ 2-3 by 4—+ in—Hk. & Grev. Ic. Fil. 
1.221. A. terminans, Wall. Cat. 2168 (all the Wallichian type-sheets). | 
Chittagong Hills, alt. 0-1000 feet, C. B. Clarke. | 
I have twice collected this, the barren fronds only: there is none from North India 
in the Kew Herbarium, and Wallich's Herbarium No. 1033 is a blank sheet of paper. I 
quote no synonyms, for Baker (Syn. Fil. 420) takes as the type of his 4. virens, Hk. A 
Grey. Ic. 221, and then says “ free veinlets none;" whereas Hk. & Grev. Ic. abounds in 
free veins. The fact is that the fronds of this species without free included veinlets are 
A. flagelliferwm. This fern is hardly separable as a var. from 
A. subcrenatum, Hk. & Grev. Ic. Fil. t. 110. Often proliferous, the free included vein- 
lets having a tendency to regular series between the main veins.—4. proliferum, 
Hook. Ic. Pl. t. 681-2. Pweilopteris terminans, Bedd. Ferns South. India, t. 203. 
.-Polybotrya virens, Bory; Hook. 2nd Cent. Ferns, t. 88. Heteronewron proliferum, 
Fée, Ze: Mém. Foug. t. 55. 
Appears plentiful in Southern India; no example from North India. 
12. A. cosratum, Wall. Cat. 26. Barren pinne about 11, 8-14 by 2-27 in., caudate, 
~ Stout in texture, drying red, costal arches none or obscure from the presence within 
them of other veins; secondary areolation copious, with included free veins ; fertile 
pinnz 6 by 1—1 in—Hook. Sp. Fil. v. 262 as to var. a only. Pæcilopteris costata, 
Bedd. Ferns Brit. Ind. t. 113. 
Round Bengal in the lower hills, alt. 0-3000 feet; from Nepaul to Chittagong, common. 
One of the best marked among the Indian Acrostichums : its large size, its drying red, 
its want of costal arches to the midribs of the barren pinne, easily distinguish kee 
all others. Tt has been joined with Meniscium deltigerum, Wall., and with xa pner | 
virens, Wall., and the descriptions founded on material thus jumbled are not EENS 
but the fern itself is. 
13. A. rricuspr, Hook. Sp. Fil. v. 272, t. 304; Hk. & Baker, Syn. Fil. 422. Gymno- 
Pteris tricuspis, Bedd. Ferns Brit. Ind. t. 53. ` 
Sikkim; Goke, below Darjeeling, alt. 1500 feet. eee 
Scales of the rhizome lanceolate, hair-jointed, chestnut-coloured. Barren frond with 
the upper part of one or more of its lobes frequently fertile; but similar varieties occur 
—— n many Acrostichums, as in A. viscosum, flagelliferum, &c.—This fern was first brought 
.. to Mrs. Atkinson by her Bhotea collector, who got it on trees on the Goke spur: many 
