Leonard — Genus Taenitis, with Notes on remaining Taenitidinae. 261 



better in the longitudinal section shown in Fig. 5 ; (a) is a vein cut trans- 

 versely in its course out towards the margin, and (b) is the commissure cut 

 longitudinally. It is seen how the sporangia are formed along its whole 

 length and are developed irregularly. 



Young material for developmental purposes was obtained from Singapore, 

 but it was too young to show the first origin of the sorus. There can be no 

 doubt, however, that they are of superficial origin, since in some cases an 

 expanse of leaf of over half an inch in width extends beyond the sorus, 

 with a complicated network of veins. 



Sporangia. — The mature sporangium does not differ markedly from the 

 type seen in Blechnum. No obliquity has been seen in the aunulns, and 

 rupture takes place by means of a lateral slit. The annulus is composed of 



a b 



Fio. 5. — T. li/eohnoides. Longitudinal section through sorus. 

 (//) Vein out transversely. (7>) Commissural vein cut longitudinally. 



from sixteen to eighteen indurated cells — a smaller number than that of the 

 typical Blechnum, and it is interrupted at the stalk. The stalk is three- 

 celled, and of medium length. The spores are tetrahedral. 



From the stalk of the sporangium there grows a hair. Being inserted on 

 the stalk below the sporangial head, it is similar in position to the glandular 

 hair of Nephrodium. It is probable that its function is a protective one, and 

 that it takes the place of the absent indusium, since in some eases the hairs 

 were seen to arch over the sporangia and cover them. 



THE REMAINING GENERA COMMONLY KNOWN AS 

 TAENITIDINAE. 



ESCHATOGRAMME. 



Of the remaining Taenitidinae, the genus which resembles Taenitis most 

 closely is Eschatogramme. This Fern has been known under many names. Its 

 present designation was introduced by Trevisan (1850). Diels ((5), p. 303) 



