ZOOLOGY AND BOTANY, MICROSCOPY', ETC. 67 



dition to a condition of two endoderraal layers, one external and the 

 other internal, ronnd the ring of bundles as a whole. This transition is 

 independent of the distance at which it occurs from the node. The 

 two rings of endodermis fuse here and there, leaving islands of paren- 

 chymatous tissue in the interfascicular region. At the point of junction 

 of the two layers a single cell may show radial bands on three or four of 

 its walls or two bands on the same wall. 2. As to the prothallium, if 

 the spores are sown thickly the prothallia remain small and show one 

 growing point only and usually bear only one kind of sex-organ. If the 

 spores germinate at a distance from each other, leaving enough space for 

 the prothallia to develop fully, the latter become very large and develop 

 a meristem all round on the circular margiu, and produce archegoma 

 first and antheridia later. It is possible to prolong the life of the pro- 

 thallia beyond their normal span, by removing the embryo and protect- 

 ing them from heat ; quite possibly they could be kept growing for over 

 a year. 



^ Australian Ferns and Mosses.* — W. W. Watts publishes notes on 

 cryptogamic matters. 1. He proposes and defines a new tribe of Poly- 

 podiaceae — namely, Dryopteridese — in order to avoid [a) the unscientific 

 separation of Phegopteris from the vicinity of Dnjopteris ; {b) the inclusion 

 of exindusiate ferns among the Aspidieaj ; and (f)the growing cumbrous- 

 ness oii\\ege\m?> Dnjopteris Vb's, defined in Christensen's " Index Filicum." 

 This new tribe includes Lastrea, Nephrodium, Phegopteris, Goniopteris 

 and Mp-niscium, all regarded as genera. Twenty-seven Australian species 

 fall within the limits of the new title. 2. He describes and figures a 

 new fern, Athyrliim hiimile, from the Ellenborough River. 3. He 

 publishes notes and records of the following ferns — Hymenophyllum 

 peltatum (Poir) (the British H. Wilsoni) ; H. rarnm R. Br. ; Dryopteris 

 acuminata (Lowe) and var. cristata (a new variety) ; Platyzoma micro- 

 phyllum. 4. He also gives a description and figures of Fissidens 

 {AmblyothalUn) humilis Dixon & Watts, a new moss from Newcastle, 

 New South Wales ; and publishes notes and records of the following two 

 mosses — Leptostomiim indinans R. Br. and Hampeella pallens (Lacoste) 

 Fleischer, with the interesting synonymy and distribution of the latter. 



Apogamy in Phegopteris and Osmunda.f — Elizabeth D. Wuist 

 describes the production of apogamous embryos on prothallia of 

 Phegopteris polypodioides, Osmunda cinnamomea, and 0. Glaytoniana in 

 cultures on Prautl's and Knop's full solutions, and certain modifications 

 of the Prantl's solution. The first cases of apogamy were observed 

 about six months after the spores of Phegopteris were sowed on Prantl's 

 solution from which ammonium nitrate had been omitted. Similar 

 cases of apogamy were obtained on Knop's full solution in six months. 

 The development and morphology of the embryos are described. 

 Apogamous embryos of the two species of Osmunda were obtained on 

 Prantl's full solution, and on the solution with ammonium nitrate and 

 magnesium sulphate respectively omitted. 



* Proc. Linn. Soc. New South Wales, xli. (1916) pp. 377-86 (1 pi.). 

 t Bot. Gaz., Ixiv. (1917) pp. 435-7. 



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