Fig. 141.— a, B, Botrychium simplex, slightly enlarged; C, B. tertwtum, X 5^ : D, leaf 

 segment of B. lunaria; E, leaf segment of B. I'irginianum, natural size; F, portion 

 of sterile leaf segment of Hclmintliostachys Zeylanica; G, fragment of the sporan- 

 giophore of the same enlarged. A, B, C after Luerssen; D, F after Hooker. 



