MAHOGANY 



Annual ring). This latter character is even more constant than 

 the presence or absence of a Pore-ring which may be partially 

 dependent upon climatic conditions. I regard Gamble as the 

 most reliable authority upon all woods embraced within his 

 compendious work, as few authors have had the opportunity such 

 as he for the proper authentication of his species coupled with 

 the necessary skill and discrimination to describe them. The 

 only conclusion I can draw therefore is that our commercial 

 Mahoganies are not the wood of Swietenia, and in this I am 

 supported by the want of resemblance in the structure of the 

 specimens at Kew to our common Mahoganies. 



The chief difficulty is the doubtful authenticity of specimens 

 derived from commercial sources. 



Amongst those which I have been able to examine I distinguish 

 the following types, based chiefly upon the appearance of the 

 rays when viewed in the solid wood under the microscope as 

 opaque objects. 



(a) Rays spindle-shaped in Tangential section with a few of 

 their cells having black contents, e.g. African : Axim, Assinee, 

 Lagos, Laguna, Oganwo and an unknown species from Lagos. 



(6) Rays with a few of the cells having black contents but 

 linear in shape on a Tangential section, e.g. African, Panama, 

 Tabasco and Mexican Cedars. 



(c) Rays medium sized, coarse-celled, no black contents, wood 

 dense and cold to the touch, e.g. Panama, St. Domingo, City 

 St. Domingo and Cuba Mahoganies. 



(d) Rays of irregular height in Tangential section, no black 

 contents, Bermuda, Honduras, and Tabasco Mahoganies. 



(e) Rays short in proportion to their width in Tangential 

 section, no black contents, Pores scanty in the outer part of 

 the ring and marked by the frequency of pairs (in Transverse 

 section) divided by the rays (i.e. not by ordinary septa), e.g. 

 Caoba. 



My specimen of the last type was one of those sent to the 

 Paris Exhibition by the Mexican Government and passed on to- 

 me by the kindness of Sir Wm. Th. Dyer. It was marked, 

 " Caoba : Nombre scientifico, Swietenia Mahagoni." It is 

 interesting inasmuch as it has a character absent in the common 

 Mahoganies which agrees partially with Gamble's description, 

 viz. in the scantiness of the Pores in the outer part of the ring. 



A precise description of the characters of the various varieties 

 of Mahogany is at present impossible. Plate III. figs. 19, 20- 

 and 22. The two first are taken from sections by Nordlinger. 



33 



