CHAPTER 



XXXIV. 



LONCHITIS, LinnoBus. 

 (Lonch-i'-tis.) 



N Hooker and Baker's " Synopsis Filicum " Lonchitis forms 

 Grenus 23. Mettenius unites it with Pteris, from which it 

 differs only by the position of the sori (spore masses). The 

 name is derived from lonche, a lance, in allusion to the 

 shape of the fronds. The distinguishing characters reside in 

 the disposition of the sori, which are marginal and placed in the sinuses 

 (depressions) of the fronds, and in the shape of these organs, which usually 

 are more or less reniform (kidney- shaped), but sometimes considerably 

 elongated. The involucres, of the same shape as the sori, which they cover, 

 are of a parchment-like texture, and are formed of the reflexed margin of 

 the fronds on which the spores are produced. So far as we know, the 

 geographical distribution of the genus Lonchitis is limited to Africa and the 

 adjacent islands, Mauritius, Bourbon, Madagascar, &c., though it is reported 

 by Linden that he collected L. Lindeniana (L. imhescens) in Caracas, 

 South America. 



Only a couple of species of this genus are known at present : both of 

 these are bold-growing plants, provided with underground rhizomes (prostrate 

 stems) of a fleshy nature. Their crowns, which sometimes grow a few inches 

 above the surface of the soil, are also very succulent, and produce robust 

 fronds, borne on light-coloured stalks, which, when young, are of a semi- 

 transparent nature. 



