SCALY SPLEENWORT. 49 



pinnate. The lobes are half-oval and alternately placed, their 

 margins usually free from teeth or other indentations. The 

 general outline of the frond, ignoring the sinuosities, is a 

 narrow lance-shape, and its texture thick and leathery. The 

 colour of the upper surface is a rich deep green, but the under- 

 side is so completely covered by the overlapping scales that 

 there is scarcely a suggestion of green visible. For the same 

 reason the sori must be carefully looked for, and it will be seen 

 that owing to the protection afforded by the scales the plant 

 has felt justified in reducing the indusium to very slender pro- 

 portions. Sometimes, indeed, it is represented by a mere ridge 

 along the nerve from which the sorus springs. The veins form 

 a network by their branches uniting. (Plates 42, 44, 48.) 



When the new fronds unroll the scales have a silvery 

 appearance, which deepens into pinky-brown as they get older. 

 The development of the sori gives a distinctly red hue to the 

 underside and justifies the name Rustyback. There is no doubt 

 that this scaly coat is of use to the plant in preventing excessive 

 evaporation from its fronds in continued dry weather. From 

 its occurrence on dry rocks and walls it must be at times sub- 

 jected to considerable trials in this respect. Its lobes then curl 

 over towards the rachis, which also curls on its length, and it 

 wears precisely the aspect of a dead and withered plant. But 

 a fall of rain will cause the fronds to expand again and present 

 their opaque green surfaces to the light. In this apparently 

 dead condition the fronds have been gathered and used as an 

 artificial bait in sea-fishing. 



The Scaly Fern is pretty generally distributed in England, 

 but it is rare in the Eastern Counties and the Midlands. It is 

 most plentiful on the west side of the island, and it extends 

 northwards as far as Argyll and Perthshire. It occurs in 

 Ireland, especially south and west, in some districts becoming 

 one of the most familiar weeds thickly studding the walls and 

 stone dykes, frequently in company with Wall-rue Fern and 



