362 



The fundamental tissue is composed of spongy mesophyll consisting of thin- 

 walled, irregularly shaped cells, with intercellular spaces, and running through the 

 length of which, at regular intcrN-als, are oil ca\'ities and bundles. 



The bundles ha\-e their xylem abnormally orientated, and are surrounded 

 b\' a protective sheath of endodermal or parenchymatous cells enclosing, along 

 with the bundle, a small number of sclerench\-matous cells on the outer edge of 

 the phloem. 



Scattered through the spongy mesophyll are nucleated or pitted cells, — 

 the transfusion tissue. 



The oil glands are small and surrounded with regular secretory as well as 

 protecti\'e cells, and occur in the same plane as the bundles. 



The stomata occur on the inner face of the leaf, the physiological signifi- 

 cance of which is identical with that of .1. Cunninghamii and the Callitris. 



By comparing this structure with that of .4. Cunninghamii distinct differ- 

 ences are found. Here the oil cavities and bundles are in the same plane, the 

 hypodermal cells are less numerous, and the transfusion cells belong to a different 

 class,— features that support the differentiation of the species, if not a sub-class. 



IV. TIMBER. 



(fl) Economic. 



This is a fine forest tree attaining sometimes a height of over 150 feet, and 

 posssssing a pale-coloured, fissile timber, utilised for similar commercial purposes 

 as "Hoop Pine," A. Cunninghamii. 



It is widely distributed on the Coast District of Queensland, and flourishes 

 well as an introduced tree in the other States, and is here strongly recommended 

 for forest culture as one of our future supplies of softwood. 



Trans\-erse Tests of Timber, Araucaria BidwiUi. 

 (Standard size, 38 in, x 3 in, x 3 in.) 



No. I. .\o. 2. No. 3. 



Size of specimen, inches ... ... ... Hi-^H; 1)2-96 ' \^ 2 ■()(); 02-97 B2-98; D 298 



Area of cross section, square inches ... ...: 8-82 8-88 8-88 



Breaking load in lb. i)er square inch ..." 3.165 2,290 1-74- 



Modulus of rupture in lb. |)er square inih ... '^'•553 I 4.721 | 3.555 



elasticity ,, ,. ... 1,822,500 I 1,600,000 i 959,210 



Rate of load in lb. j)er minnt. j 452 3S1 [ 387 



