IXTERCEIXULAR CANALS 263 



GENERAL 



A Brazilian specimen (Yale No. 3126) labeled "arrnda brava" but 

 not identified shows concentric rows of small ducts with here and there 

 a larger resinous pocket. The ducts are apparently normal and it 

 seems probable that the wood belongs in the group of Leguminosse 

 mentioned on page 434 of the former paper. 



Dixon (18, p. 465) says in reference to a market specimen labelled 

 "African walnut" : "Parenchymatous laminae — often with black deposit 

 in intercellular spaces."' Of another specimen he says (p. 466) : "Cir- 

 cumvasal parenchyma spreads tangentially to form laminae, which often 

 develop intercellular spaces in tangential series, filled with dark secre- 

 tion, and extends radially along rays." The identity of these specimens 

 is unknown. Boulger (19, p. 322) mentions two woods known on the 

 market as "African walnut," one {Trichilia sp.) belonging to the Melia- 

 ceas, the other (Boswellia Klainei) to the Burseracese. Woods of 

 both of these families are known to develop intercellular canals. Ac- 

 cording to Unwin (23, p. 326) the wood most commonly sold as 

 African walnut is Lovoa Klaineana of the family Meliacese. 



Dixon (18, p. 454) says in reference to a specimen from the Dublin 

 National Museum, labelled "turiballi. uriballi or eurebally, or Guiana 

 mahogany": "Rays uniform (except for occasional giant rays). 



. . . Giant rays with bowed sides, many cells across, with dark 

 contents in middle cells, a circular curve or even a space." The identity 

 of this wood is unknown, but the present writer is of the opinion that it 

 belongs to the Anacardiacese. 



With reference to conifers, the writer has noted greatly enlarged 

 resin ducts in the fusiform rays of Picea sitchensis. These are scat- 

 tered all through the specimen (which is a portion of an airplane strut) 

 and are distinct to the unaided eye as dark specks or dots. They are of 

 the shape described by Jeffrey (20) in a fossil Sequoia and by Jones 

 (17) in Cedriis. 



In a specimen of Pseudotsiiga taxifolia (also part of an airplane 

 strut) a slightly malformed portion was found which on tangential 

 section is roughly circular and about one-half inch in diameter. In 

 this region the rays are decidedly abnormal, being multiseriate (up 

 to 7 cells wide) and up to 100 cells in height. Each of these enlarged 

 rays usually contains a single small resin duct, though in some cases 

 two were found, and in a few instances there was none. The wood 

 outside this region was normal. 



