INTERCELLULAR CANALS 261 



large, empty radial canals were found in Leptospermum javanicum, 

 Eugenia cuprea (sometimes more than one in a ray), and E. sexangu- 

 lata. 



RosacecB. — The presence of canals and cavities of the gummosis type 

 in the woods of the Prunoidese is a matter for common observation. 

 Such canals are, for example, very commonly found in the wood of 

 Primus serotina. The writer has also observed them in a Philippine 

 specimen (Yale No. 1676) labeled "Luisin Gubat, Indet," and believed 

 to be Pygeum sp. 



Moll and Janssonius (16, III, pp. 207-263) have investigated the 

 woods of two species and seven varieties and forms of Pygeum from 

 Java. In P. parviflorum vertical gum canals in unbroken tangential 

 lines were of common occurrence. In P. latifolium, P. latifolium var. 

 tonientosa form lanceolata, and P. latifolium var. nervosa, radial canals 

 without contents and said to be of schizogeneous origin were found. 

 Of two different specimens of P. latifolimn var. tomentosa, one con- 

 tained the typical vertical gum ducts while the other contained schizo- 

 genous radial canals. In the latter specimen the rays averaged con- 

 siderably larger than in the former. 



The conditions in the Rosaceae closely parallel those already noted 

 for the Myrtacese. 



Rutacccc. — The occurrence of gum or mucilage canals has already 

 been noted in species of Xanthoxylum, Esenbeckia, and Fagara (?). 

 The writer has found them in three other woods, all from Brazil. A 

 specimen of "guarantan" (Yale No. 3907), believed to be Esenbeckia 

 leiocarpa, shows ducts as previously reported for E. febrifuga. 



Specimens of Balfourodendron Riedelianum (Yale Nos. 3903, 3167) 

 have vertical canals common in tangential rows in association with 

 wood parenchyma. They are filled with a yellowish or brownish mass. 



A market specimen of "pau amarello" (Yale No. 3929), identified as 

 Eiixylophora paraensis, contains a patch of wood parenchyma (re^ 

 sembling a large pith fleck) with small ducts with reddish contents 

 scattered in it. This structure was not observed in other specimens of 

 this wood. 



Sapindacecc. — "The parenchymatous w^ood of Dilodendron bipin- 

 natnm is characterized by a kind of gummy metamorphosis, a sub- 

 stance resembling gum being excreted in the vessels and in canal-like 

 cavities." Solereder (2, p. 233). 



