LINNEAN SOCIETY OP LONDON. 87 



II. Exhibition of PapMopedilum Capsules as affected by 

 Hybridization. By E. A. Rolfe, A.L.S. 



It consisted of a series of PapMopedilum capsules, from the col- 

 lection of Reginald Young, Esq., of Liverpool, partly obtained by 

 self-fertili'/ation and partly by hybridizing, wath the object of 

 ascertaining whether any modification in shape or other details 

 could be traced to the influence of the pollen parent used. One 

 sheet showed seven capsules from a single plant of P. concolor, 

 obtained by crossing with various other kinds ; and as they differed 

 between themselves, the question arose whether this variation 

 was due to the varying influence of the different pollen parents. 

 In order to test this question, plants of two distinct species were 

 crossed and re-crossed, and at the same time a flower of each parent 

 was self-fertilized. This was repeated with several pairs of species, 

 the result being that (after deducting a few failures, which broke 

 the series) three complete sets of capsules were obtained, two of 

 which were exhibited. jVo modification, however, could be found 

 in the hybridized capsules, each of which agreed in detail with 

 self -fertilized capsules on the same plant. The pairs of species 

 were P. Mastersianum, P. tonsum, P. insigne, and P. callosmn, 

 which differ markedly in character. Of the latter series seeds 

 were also shown under the microscope ; and here, too, the evidence 

 was equally negative in character, the testa covering the hybrid 

 embryos being unmodified in shape, sculpture, and colour. These 

 hybrid embryos would germinate and produce bond fide, hybrids, 

 intermediate between, or combining the characters of the parent 

 species ; in proof of which there were exhibited coloured drawings 

 of several hybrids with their parents, and also of the matured 

 capsules, for in practice it was found that some of them were 

 fertile, and secondary hybrids had been obtained from them. 



III. On Sphenophyllum and its Allies : an Extinct Division of the 

 Vascular Cryptogams. By Dr. D. H. Scott, E.R.S., F.L.S. 



(Abstract.) 



The author explained that his purpose was not to communicate 

 any new observations, but to give a summary of our present know- 

 ledge of the group and to discuss its affinities. He pointed out 

 that the study of the Palseozoic Elora not only greatly widens our 

 conception of the three existing Classes of Pteridophyta, but adds 

 a fourth — that of the Sphenophyllales — to their number. 



The external characters of certain species of Sphenopliyllurti and 

 Trizygia were first described, and attention directed to the slender 

 ribbed and jointed stems, the whorled and superposed leaves, and 

 the great variation in the form of the leaf. The common hypo- 

 thesis, based on the dimorphism of the leaf, that Sphenophyllum 

 was an aquatic genus, was inconsistent with other facts, and 

 Mr. Seward's suggestion of a climbing habit appeared preferable. 



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