2(;0 JOURNAL OF FORESTRY 



sometime. ..-^^^ intercellular spaces filled with deposit." Same (p. 459) 

 re.^Khaya scne(/ux.,,^i^. "Laminar parenchyma rare or absent, some- 

 times with deposit ot a_i^ gum-like substance in intercellular spaces 

 and forming a dark tangential w^d across section (PI. XXX, fig. 49)." 

 Same (p. 462) re. Bntandrophragma cxcelsum: "There is rarely a 

 continuous band of intercellular spaces in these laminae with dark 

 deposit." Same (p. 471) re. Cedrela toona: "Laminar parenchyma 

 occasionally in dense zone with schizogenous spaces filled wkh dark 

 deposit." Same (p. 472) re. Cedrela scrrata: "Circumvasal paren- 

 chyma narrow, laminae occasional on outside of growth-zone, about 10 

 cells thick, sometimes with schizogenous spaces filled with dark deposit. 



Only vertical canals have been found in the woods of the Meliaceae 

 and they are of the gummosis type, at least their final stage indicates 

 plainly the breaking down of the surrounding tissue. These canals are 

 usually conspicuous and seriously weaken the resistance of material to 

 longitudinal shear. 



The genera reported are : Carapa, Cedrela, Bntandrophragma, Melia, 

 Sandoricum, and Sivietenia. Further investigations will likely increase 

 the list materially. 



Moringacecr. — Vertical canals were found by Moll and Janssonius 

 (16, II, pp. 513, 515) in the wood parenchyma of Moringa sp. Through 

 their lysigenous enlargement they broke down portions of the adjacent 

 rays. They are apparently without contents. It is interesting to note 

 that in this instance the canals, instead of being in rows or layers, as 

 is usually the case, are scattered irregularly. (16 II, fig. 144, p. 514.) 

 The presence of one or two gum canals in the pith only had been 

 noted by previous investigators. 



This family consists of only one genus. 



Myrtaccce. — In the former paper is this statement (p. 437) : "Al- 

 though secretory cavities occur in the leaf and ground tissue of the 

 axis of this family, the writer has been unable to find references to 

 secretory canals or cavities in the wood." Since then occasional ref- 

 erences have been found in descriptions by various authors, notably 

 Boulger (19) and Baker (26), who refer to the canals as "gum-veins." 

 They are very common in the wood of many species of Eucalyptus. 

 Boulger (19, p. 128) also refers to Angophora intermedia as "subject 

 to gum-veins." 



According to Moll and Janssonius (16, III, pp. 387-9, 403, 406, 412, 

 437-8, 486) vertical canals sometimes occur in Rhodamnia cinerea and 



