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diameter, gradually tapering to both extremities, and elongates 

 above into slender segments. Segments are widely parted, making 

 a gentle curve from origin, and are often loaded with irregularly 

 inserted and similarly formed branches. The height of plant, 

 when fully grown, attains 30-50 cm. in length. 



Of the structure of frond, there are three layers. The axial 

 layer consists of longitudinally running and loosely set, filamentous 

 cells which are connected with those, forming the inner wall of 

 the intermediate stratum. This axial tissue becomes destroyed 

 as the plant advances in age, making the frond tubular. Outside 

 of this, there is a thick intermediate layer which is composed of 

 large, roundish-angular and almost hyaline cells. These become 

 gradually smaller as it proceeds towards periphery, and finally 

 pass into infra-cortical tissue. The latter is formed of smaller 

 coloured cells and is covered by a layer of anticlinal epidermal 

 cells which are often transversely divided into two. All the cells 

 are united to each other by the formation of pit which appears 

 to be similar as it is well known in cells of florideae. 



Mode of growth of frond is trichothallic, tliat is, the growing 

 apices of branches dissolve into a tuft of penicillate hairs which 

 are free from each other down to the base and greenish-olive in 

 colour. These hairs consist of jointed cells which are here and 

 there divided by longitudinal walls, and the articulations appear in 

 surface-view to be composed of a few cells zonally arranged. By 

 repeated division of the basal cells of hairs, new parts are added 

 to frond, as it is well known to plants of this' genus. After- 

 wards, they are dropped off, leaving the apices of fully grown 

 branches slender and naked. .' 



Sori of both sexes form, on different individuals, irregularly 

 roundish, slightly elevated, warty prominences which are densely 

 scattered around branches, except in the upper segments and 



