VIII THE PTEIUDOFIIYTA—OPHIOGLOSSACEM 253 



SO that there arc four bundles at the base of the petiole. 

 Higher up a cross-section shows ten bundles arranged about 

 the periphery, and an inner one, formed by the branching of 

 one of the others upon the upper side. This inner bundle, and 

 those of the upper side of the stalk, furnish the bundles for the 

 sporangiophore. 



The sporangiophore is long-stalked and in general appear- 

 ance intermediate between that of the other genera, but a 

 careful examination shows that it is much more like that of 

 Botrychiinn. It is pinnately branched, but in an irregular way, 

 and the small branchlets bear crowded oval sporangia, which 

 open longitudinally on the outer side, and not transversely as 

 in the other genera. The tips of the branches, instead of 

 forming sporangia as in Botrychiuni, develop into green leaf- 

 like lobes, which upon the shorter branchlets are often arranged 

 in a rosette of three or four together, with the sporangia close 

 below them (Fig. 122, D). This at first sight looks as if the 

 sporangia were produced upon the lower side of these, like 

 Equisetuni, but a very slight examination shows at once that 

 this is only apparent, and the sporangia are undoubtedly 

 outgrowths of the branches as in Botrychium. The green lobes 

 are seen to be only the vegetative tips of the branches, or 

 perhaps better comparable to such sterile leaf segments as are 

 not uncommon in Osmunda Claytoniana. 



Unfortunately the life history is absolutely unknown, and 

 its histology is also too imperfectly known to make it possible 

 at present to determine its exact relation on the one hand to 

 the other Ophioglossacese, and on the other to the Marattiaceae 

 and Filices. 



