THE ADULT SPOROPHYTE 



105 



characters are established at a comparatively early period. The rhizome (fig. 79) 

 has the leaves arranged in two rows on the dorsal side, somewhat as in Ophioglossum 

 pendulum, but the leaves are less crowded and the internodes are evident, although 

 less marked than is often the case in the very young sporophyte. The youngest 

 leaves, still inclosed in the stipular sheath of the next older one, are conspicuous as 

 blunt projections, situated between the apex of the rhizome and the first expanded 

 leaf. As the leaf breaks through the stipular sheath of the next older one the 

 sheath is split into two stipule-like flaps, which much resemble superficially the 

 stipules of the Marattiaceae. From near the base of the leaves on the flanks of the 

 rhizome and belonging to the ventral portion of the stem there arise the thick fleshy 



Fig. 78. 



A. Sporophyll of Helm'mthoitachys, somewhat reduced. 



B. Base of sporangiophore, about natural size. 



C. Stoma. X200. 



D. Four sections of the sporophyll Fig. 3 passes 

 through the base of the spike, sp; 4, section of 

 peduncle of spike. 



roots, which resemble those of the other Ophioglossaceae. According to Prantl 

 (Prantl 1) and Farmer (Farmer 2), the roots bear no definite relation to the leaf, 

 and the number as a rule somewhat exceeds those of the leaves. The roots branch 

 monopodially, as in the larger species of Botrychium, but Farmer states that the 

 lateral rudiments often prove abortive, or fall away at an early period, so that the 

 roots are apparently unbranched. This behavior recalls the condition found in 

 Botrychium lanuginosum. 



The leaves are very different in general aspect from those of the other Ophio- 

 glossaceae, but are really not very different in their method of branching fronvthe 

 ternate forms of Botrychium. There are still traces of the three primary divisions 

 of the first leaves which undergo subsequent divisions, so that the leaf has a palmate 

 form (plate 8, B). To a certain extent, however, these divisions are the result of 



