M'Nab — A Revision of the 8pecies of Abies. 673 



LIY. — A. Revision" of the Species of Abies. By William Ramsay 

 M'Nab, M. D., Edinburgh, Professor of Botany, Royal College of 

 Science for Ireland. (With Plates 46, 47, 48 and 49.) 



[Read June 26, 1876]. 



Last year I presented to the Royal Irish Academy a paper (aniea, 

 p. 209), in which the anatomy of the leaves of the section Tsuga 

 of the genus Pinus vs^as described, and in the present paper I propose 

 to continue the investigation of the anatomical structure of the leaves of 

 the same great genus. The sections to which I shall now direct atten- 

 tion are Abies of Endlicher and Parlatore, and Pseudotsuga of Carriere 

 -and Bertrand, the former including a considerable number of species of 

 which the common European silver fir may be taken as the type. 

 Much confusion has been caused by Linnaeus in 1753 falling into an 

 •error as to the application of the names Picea and Abies — an error 

 which was corrected by Duroi in 1771 ; but in this paper I shaU not 

 follow Parlatore in calling the common silver fir (generally known by 

 the name of Abies pectinata of De CandoUe) Pinus (Abies) Abies of 

 Duroi ; but shall adopt the more commonly used A. pectinata. 



Dr. C. E. Bertrand"* enumerates and briefly describes the anatomical 

 ■characters of twenty-two species of Abies. All Bertrand's forms, with 

 .a single exception, I believe I have been able to examine ; and while 

 we agree in many most important points, still in others I find con- 

 siderable discrepancies in our results. Perhaps this may result from 

 an examination of but few examples of each species, and this I have 

 tried to avoid by examining as many specimens as I could obtain, both 

 living and dried. A very large number of specimens have been exa- 

 mined, and many thousands of sections cut — the greater part of my 

 ■spare time for twelve months past having been devoted to the work. 



Great confusion exists in the nomenclature of this section ; the 

 synonymy is very complex, and the cultivated forms frequently do not 

 agree with the species described by Botanical authors. It has, there- 

 fore, been difficult in many cases to discover what the true plant of 

 the original describer was, but I have been very fortunate in obtaining 

 a great deal of information regarding the cultivated species introduced 

 into Britain within the last twenty-five years from my father, who has 

 cultivated most of the species with the greatest success, and whose 

 accurate and extensive knowledge of this genus is well known. All 

 the forms introduced by Jeffrey have been raised from seed in the 

 Royal Botanic Garden at Edinburgh, and I have thus been able to 

 •obtain, from the Museum, and from the Edinburgh Botanic Garden, 

 authentic specimens of the different forms for examination. To Dr. 

 Hooker and Professor Oliver I am very deeply indebted for permission 



* Anatomie Comparce des Tiges et des Feiiilles chez les Gnetacees et les Coni- 

 feres. Paris, 1874. 



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