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THE A M ERIC A N NA T URA LIST [Vol. XLl 



leaf base terminates in a very small pointed lamina that is usually 

 bent over, suggesting the circinate vernation of the true ferns. In 

 most of the terrestrial species of Ophioglossum the young leaf is 

 folded straight in the bud. Under the arched hood formed by the 

 lamina is the young spike (*Sp.) which almost equals the lamina in 

 length. 



Fig. 3, B, shows a somewhat older stage. The leaf has now 

 become somewhat flattened, but there is no clear demarkation 

 between the petiole and the small lamina. The fertile segment, 

 which shows as yet no differentiation of the peduncle and spike, 

 is conspicuous, and merges gradually into the thick petiole of the 

 leaf whose margins are more or less distinctly winged and pass 

 imperceptibly into the lamina above the insertion of the fertile 

 segment. The interpretation of the latter as terminal and the 

 sterile portion as a lateral appendage coherent with it would seem 

 entirely plausible. An interesting case is shown in Fig. 3, E, 

 where the lamina is almost entirely suppressed, and the terminal 

 character of the spike is very evident. 



As the leaf develops there is a very great increase in size of the 

 lamina, which, in some of the largest individuals collected in Cey- 

 lon and Java, reached a length of one and one-half metres, or even 

 more. These large leaves usually have the lamina dichotomously 

 divided, and strikingly resemble the long (ir()<)j)iiig leaves of some 

 species of Platycerium. Nevertheless even in these huirer leaves 

 the segments are quite destitute of a mid-ril). This stops at the 

 base of the peduncle of the spike into which it is continued. The 

 spike in these large specimens is correspondingly large, and some- 

 times attains a length of 25 to 30 centimetres, with a breadth of 

 more than a centimeter (Fig. 3, I)). 



Undoubtedly allied to O. pendulum is the rare O. intermedium 

 Hook. (Fig. 4). ^Miis is also perhaps the nearest ally of O. .^'im- 

 plex. In the ordinary form iVh^. 4, A, B) this is not nnhke a 

 small specimen of O. pendulnw, hnt it i> riiridly ni)rioht instead 



leaf nnich >n,aller'an.l nlore >harply ..-paratrd from th.' petiole. 

 As in i). pendulum, however, the petioh- is pn.longed into the 

 peduncle of the spike with the same niid-rib like thickening, 

 caused by the coherence of the basal part of the peduncle with 



