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of ferns in the open air fernery, and which condition is 

 almost impossible of attainment by any other means. 



H. Stansfield. 

 Sale, December, 1917. 



[Asplenium lanceolatum microdon, although under double 

 glass protection, was killed outright in Reading by the 

 frost of the winter of 1916-17, as the species had been by a 

 previous severe winter. This species (lanceolatum) 

 appears with us to be almost, but not quite, as tender as 

 A. marinum. Many choice varieties of Polystichum 

 angulare, grown in iiots, suffered severely, while those 

 planted out, whether in the open ground or in frames, 

 were practically uninjured. — Editor.] 



POLYDACTYLISM IN POLYSTICHUMS. 



Every raiser of Polystichums (especially of P. angulare) 

 from spores must have been struck by the increasing ten- 

 dency of late years for polydactylous forms to appear 

 among the seedlings. Unfortunately the polydactylism 

 is invariably more or less irregular, being greater in some 

 pinnae than in others, while it is always missing from a few 

 of them. This want of thoroughness is a defect in the 

 polydactylous forms inasmuch as it causes the fronds to 

 be more or less unsymmetrical. Occasionally a frond will 

 appear which has all the pinnae affected, but no one has yet 

 succeeded in raising a form which was constant throughout, 

 i.e., in which all the pinnae of all the fronds shewed this 

 character. The first polydactylum recorded was found in 

 Tipperary in 1857, named by the late Mr. Thomas Moore, 

 and distributed by Mr. R. Sim, of Foots Cray. It was 

 a poor thing, being a small grower with a tendency to 



