88 



VASCULAR CRYPTOGAMS 



(X I2o). 



Zealand ; Hymenophyl- 

 lum and Trichomanes 

 nearly loo species each, 

 exceedingly delicate and 

 graceful ferns, growing 

 mostly on the trunks of 

 trees and damp rocks, 

 often within reach of the 

 spray of waterfalls, in the 

 moister and warmer parts 

 of the globe. The smaller 

 species of Hymenophyl- 

 lum are known as ' filmy 

 ferns.' The Hymeno- 

 phyllacese may be re- 

 . . J , „. , „ garded as the simplest 



Fig. 64,.— a, germinating spore and prothallmm of Hyiizcno- » '• 



j>hyllnm\ B, C, D, stages in development of prothallium andarcprobably the oldeSt 

 (After Luerssen.) ^ ^^ r r j 



family of ferns, and pos- 

 sibly form a connecting link be- 

 tween the Muscinese and the Vas- 

 \ cular Cryptogams. 



Literature. 



Mettenius — Ueber die Hymenophyl- 

 laceen, 1864. 



Janczewski and Rostafinski — (Prothal- 

 lium) Mem. Soc. Nat. Sc. Cher- 

 bourg, xix., 1875. 



Goebel— (Germination) Ann. Jard. Bot. 

 Buitenzorg, vii., 1887, p. 57. 



Prantl— Untersuchungen zur Morpho- 

 logic der(^efasskryptogamen, Heft I. 



Bower — Annals of Botany, vol. i., 1887, 

 pp. 183 and 269. 



Order 5. — Osmundace^e. 



The prothaUium of the Os- 

 mundacese is characterised by its 

 strong tendency to propagate itself 

 vegetatively, by means of adventi- 

 tious shoots, and is commonly 

 dioecious, springing directly from 



Fig. 65.-Prothaiiium of Osmunda the spore. It is usually ribbon- 

 regaiis L. a, antherids ; w, ghapcd, with a wcll- defined midrib 



rhizoids; 7', growing point. (After ^'■'- r^ J 

 Goebel.) 



