NOTE ON FERNS COLLECTED AT PACSMAEHI, C.P. 499 



8,000 feet. The strata have a dip of 100° to the North. The 

 sandstone is readily dennded hence the formation of the character- 

 istic ravines which start abruptly from the edge of the plateau with 

 a sheer drop of anything up to 1,000 or 1,500 feet. 



Climate. — The highest temperature recorded is 104° F. in June, 

 the lowest 30° F. in December. The average day temperature in 

 the cold weather is 71-3° F., dropping at night to 47-5° F. In 

 the hot weather the average maximum is 93-1° F, and the minimum 

 75-1° F. In the ravines the temperature is more uniform. The 

 rainfall is heavy averaging 77 inches annually. The rains com- 

 nience early in June and continue into October. 



Notes of the Fern Flora. — As mentioned above, the full glory 

 •of the ferns is to be seen in the shady moist-ravines. There the 

 beautiful tree ferns Gyathea sioinuloba, Wall., Alsophila glabra, 

 Hook., and Angioioteris evecta, Hoffm., flourish, the first raising its 

 feathery crowns to a height of 15-20 feet. On the banks where 

 the soil has collected are the humbler but not less graceful herba- 

 ceous species. Growing on the graveilj'" margins of the streams 

 are clumps of the Royal Fern {Osmunda regalis, Linn,) while on the 

 half submerged rocks Acrostichicm lanceolatum, Hook., finds a home. 

 In the spray of the water falls Maiden Hair (^Adianticm capillus- 

 •veneris, Linn.) flourishes, while on the higher levels occur Nephro- 

 lepis. cordifolia, Bak., and Neplirolepis exaltata, Schott., protected in 

 the less humid conditions by their cuticularised fronds. On the 

 more open stretches where gravel and sand have been deposited 

 Fquisetum dehile, Roxb., a horse tail pushes its rhizomes, contrasting 

 strangely in its rigid xerophyllous stems, with its hygrophyllous 

 relations. Psilotum triquetrum, Sw., flourishes in places in the 

 cracks in sheer walls, justifying its xerophyllous structure by the 

 places where it finds a home. 



Amongst the rocks on the plateau the commonest ferns, the Silver 

 fern, (^Cheilanthus farinosa, Kauff".) and Adiantum caudatum, Linn., 

 the Strawberry maiden hair, so called from its runner-like fronds. 

 The hypogeal parts of both are annual, the former is further 

 protected in the dry positions in which it grows by the silvery 

 •coating of hairs on the under surface of the leaves and the habit of 

 rolling its leaves in the dry season with the dorsal surface upper- 

 most, the latter by a covering of hairs and its prostrate habit. 

 Adiantum lunulatum, Burm., being without these protections exists 

 only in the wet season. Nephrodium odoratum, Bank., is a graceful 

 fern with annual fronds, the half-exposed rhizome being protected 

 by a thick covering of chafiy scales. Ly g odium pinnatijidum, Sw., 

 is an interesting climbing fern, the annual leaves being heavily 

 cuticularised. The hardiest fern of all is Polypodium lineare, 

 Thumb, var. simplex, Sw., whose simple, almost leathery, leaves roll- 

 <ed from the margin with the cuticularised ventral surface outwards 



