Leonard — Genus Taenitis, with Notes on remaining Taenitidinae. 259 



upwards for a long distance into the petiole, but disappears before the first 

 pinnae are formed, the two straps fusing into a single meristele (Fig. 2, 5). 

 When a bud is present on the side of the petiole, the vascular supply to 

 it is taken from the adaxial end of the adjacent strap (Fig. 2, 2 and 3). 

 There is nothing remarkable about the position of the protoxylem groups. 

 There are four groups altogether, two in each strap. When the perforation 

 disappears and the leaf-trace becomes horse-shoe shaped, the four protoxylem 



i% 



Fig. 2. — Diagrammatic drawings of leaf-trace of T. blechnoides. 



groups still persist ; but when the pinna-traces are formed, the upper two 

 groups are replaced by a single median one. 



The pinna-traces arise from the margin of the leaf-trace (Fig. 2, 6). 



The Leaf. 



The leaf is about twelve to eighteen inches, and the pinnae about six 

 inches in length. In one of Lobb's specimens from Singapore in the 

 Herbarium at Glasgow University two of the lower pinnae are forked about 

 one inch from their insertion on the rachis. 



Venation. — The venation of the leaf is reticulate (Fig. '6a and b) ; see also 

 Presl (10). These reticulations are found about equally numerous on the area 

 between the midrib and the fusion-sorus, and on that between the latter and 

 the margin. But underlying the reticulation is a general course of the veins 

 towards the margin comparable with that seen in Bleclinum braziliense. 

 Beneath the sorus is a continuous vascular supply or commissure like the 

 commissure found in Bleclinum (Fig. ob). In cases where the sorus is not 

 continuous, the commissure disappears also. Thus it is seen, that the venation 

 of Taenitis corresponds essentially with that of Bleclinum, but with the 

 addition of reticulations, which are a sign of advance. 



