xxvi] 



SAGENOPTERIS 



479 



as Solms-Laubach^ states, is not wholly satisfactory : Schenk 

 points out that the frequent occurrence of detached Sagenopteris 

 leaflets suggests that they easily fell off the petiole, whereas in 

 Marsilia the leaflets do not fall off independently. The dis- 

 covery of a new type of Marsiliaceae in Brazil, which Lindman 

 has described as Regnellidium diphyllum^ (fig. 326, A), affords 

 an additional piece of evidence bearing on the comparison 



Fig. 326. A. Regnellidium diphyllum Lind. Single leaf and stalked sporo- 

 carp. (I nat. size. After Lindman.) 

 B. Cuticle of Sagenopteris rhoifolia. (After Schenk.) 



of Sagenopteris with members of this family. In Regnellidium 

 the leaves differ from those of Marsilia in bearing two instead 

 of four leaflets, and in the former the veins are repeatedly forked, 

 and do not anastomose as in Marsilia. In the possession 

 of only two leaflets Regnellidium agrees with some forms of 

 Sagenopteris (fig. 328). 



1 Solms-Laubaoh (91) A. p. 182. 



2 I am indebted to my friend Dr Nathorst for calling my attention to 

 Lindman 's paper. 



