1888.] H. F. Blanford— ^ List of tie Ferns of Simla. 313 



6,500 ft., but not higher. The fronds are thick and coriaceous, and in 

 dry weather roll up from the margins, and so remain for weeks or 

 months ; unrolling again, like Niphoholus, on the return of wet weather. 



84. PoLYPODiuM (Phtmatodes) simplex, Swartz. 

 Plate XX. 



Very abundant on trees during the rains. The lowest limit of its 

 range is rather above than below 6,000 ft., and I have gathered it up 

 to 8,500 ft., but it is rare above 8,000 ft. The fronds last only as long as 

 the rains, and they blanch, shrivel, and disappear in September. Their 

 texture is thin, the venation distinct, and they are often crimpled at the 

 edges. The rhizome is thicker than that of P. lineare, but the scales 

 that clothe it, and those that cover the young sori, are similar to those of 

 P. lineare. In the living state the two species are very different. 



85. PoLTPODiUM (Phtmatodes) clathratum, 0. B. Clarke. 

 Plate XXI. 



Quite distinct from both the preceding, though often growing with 

 P. simplex. Its lower limit is about 7,000 ft., but it is abundant on the 

 trees on the north side of Jako, a little above that level, and ranges up 

 to at least 10,000 ft. on Kumalhori and Hatu. Like P. simplex, it is 

 found only in the rains, and in texture and mode of growth much re- 

 sembles that species. But it is readily distinguishable by its narrow 

 linear fronds, the character of the venation, and the clathrate scales 

 of the rhizome and the sori. The sori are small, frequently oblong, of 

 a bright orange colour, and sometimes confluent. The scales of the 

 sori disappear at an early stage. The stipes are generally shorter and 

 the fronds longer and more linear than in the specimen figured by Mr. 

 Clarke. It is very common at Simla, and Mr. Duthie has collected it in 

 Kumaon. 



86. PoLYPODiUM (Phtmatodes) membranaceum, Don. 



Occurring only in the immediate neighbourhood of streams in deep 

 shady ravines up to about 5,000 ft. Not common. 



87. PoLTPODiUM (Phtmatodes) hastatum, Thunb. 



Very rare. In fact, I know of only one locality for it, near Simla, 

 a rock at 6,200 ft. in the neighbourhood of a waterfall. 

 41 



