324 SUMMARY OF CURRENT RESEARCHES RELATING TO 



gives off, and the leaf-trace, he compares the axillary vascular strand 

 with that of T. radicans, and also with Helminthostachys. He deems 

 the Ophioglossaceae, Botryopteridese, and Hymenophyllaceee to be in one 

 cycle of affinity. 



Vascular Connexions of Sporocarp in Marsilia.* — H. E. Allinson 

 publishes a note on the vascular connexions of the sporocarp in Marsilia 

 2)oJijcarpa. Several sporocarps are developed in acropetal succession and 

 on one side of the petiole. The latter contains a V-shaped strand, from 

 the margin of which arises the bundle of the sporocarp. Higher up the 

 strand divides into three and then into more bundles. As the vascular 

 supply of the leaflets also originates from the margin of the petiolar 

 bundles, the sporocarps may accordingly be regarded as fertile lobes of 

 the leaf. In Pteris semi^mmata is found a similar instance of pinnule- 

 strands arising from the margin of the pinna-strand. 



Two Synthetic Genera of Filicales.t— F. 0. Bower treats of two 

 synthetic genera of the Filicales, Lopkosoria and Plagiogyria. As regards 

 the former, the author's suggestion is that the further elaboration of 

 the GJeichenia sorus — namely, its closer packing and the median dehi- 

 scence of the sporangia — being impossible, Lopkosoria pndnata (Br.),, 

 formerly included in Alsophila, adopted a lateral dehiscence while 

 retaining the Gleicheniaceous character of a naked simultaneous sorus. 

 The solenostely of Lopkosoria is suggestive of the anatomically more 

 complex species of GUickenia. Lopkosoria may be the most primitive 

 member of a sequence of Cyatheacese in which the more complicated 

 members acquired a gradate sorus protected by scales. In that case the 

 erect habit of the higher Cyatheacea^ is probably secondary rather than 

 primitive. The note on Plagiogyria has been elaborated elsewhere. 



Perispore in the Filicinese.l — E. Hannig discusses the presence of 

 a perispore in the Filicineas and its systematic importance. 1. Among 

 the EufilicineEe occur related genera with and without a perispore. 2. 

 The perispore (as investigated in Aspidiam trifoliatum) is a so-called 

 " sackperispor," which is disposed loosely around the exospore, and 

 forms more or less strong folds. 3. The "sackperispor" arises from 

 the epidermal layer of the spore-vacuole ; at first it is a fine skin closely 

 applied to the spore, and afterwards grows by the formation of folds. 



4. In the exospore of A. trifoliatum there arise, long after the formation 

 of the perispore-folds, numerous and comparatively large protuberances. 



5. Pohjpodium anreum possesses no perispore, but only an exospore, 

 differentiated into three lamellae ; it also lacks an endospore. 6. The 

 absence of a perispore appears to be characteristic for the genus Poly- 

 podiwn (polypodioid spores) ; on the other hand, the presence of a 

 perispore is characteristic for the genus Aspidium (aspidioid spores). 7. 

 Apparently the perispore, broadly speaking, has a significance in the 

 grouping of the genera comprised in the PolypodiScea?, Aspleniacese, and 

 AspidiaceBS. 



* New Phytologist, x. (1911) pp. 204-6. 



+ Rep. Brit. Assoc. Sheffield, 1910, Sect. K. See also Bot. Centralbl. csix. 

 (1912) p. 197. X Flora, n. f., iii. (1911) pp. 321-46 (figs.). 



