BY JAMES II. PETRIE. 4:29 



Maerosamia eontained any actual poisouous constituent, some signs of its action 

 would have been manifest in 5 months. Cattle in the poor Macrozamia country, 

 however, would eat the plant in sutfieient quantity to keep alive, Ijut were not 

 being sujiplied with vitainine (26) . 



The dietetic deficiency theory put forward by Dr. Cleland was not accepted 

 by Professor Stewart, who has since conducted further feeding experiments. 

 These eliminate any suspicion of lack of vitamines being the cause of the disease. 

 He has obtained positive results in so far as the disease was established in animals 

 receiving a '"sufficient" diet, with an allowance of Macrozamia. It is understood 

 that the details of these later feeding experiments will be published shortly. 



In 1917, Mr. F. B. Guthrie analysed the nuts and leaves of M. spiralis, and 

 the following results were published (27) . 



Kernel- Leaves. 



Water 81.79 76,67 



Ash 1.07 .99 



Ether extract 18 .40 



Fibre 4.74 6.18 



Albuminoids .03 2.64 



Carbohydrates 12.19 13.31 



100.00 100.00 



It is important to note from these figures for the kernels, after deducting 

 the water and calculating the dry substance, that two thirds of this is starch and 

 one quarter fibre. 



Experimental Work. 



Macrozamia spiralis Miq. grows in great abundance in certain districts, north 

 and south of Sydney. A large stock of the leaves obtained from Bateman's Bay 

 on the south coast of New South Wales, was made available by Professor Watt 

 in connection with the investigation of this plant as a possible source of raw 

 material for tlie manufacture of commercial alcohol. 



The sample consisted of the entire rachis and leaflets, each about six feet 

 long. Through the kindness of Mr. 6. Wright, these were air-dried and put 

 through a disintegrator in the School of Agriculture at the University. The fine 

 dry poT\'der thus obtained weighed 10.4 kilograms. 



Proximate Composition of the Leaaes. 



A portion of the leaf-powder was dried at 100° C. for water content, then 

 incinerated to obtain the amount of crude ash. Another portion was completely 

 extracted successively with various solvents, in a Soxhlet extractor; the extracts 

 were evaporated, and the residues dried at 100° and weighed. There was left 

 an insoluble powder containing the cellulose, fibre, and other indefinite substances. 

 The following results were obtained for the air-dried leaf-powder, and have 

 been also calculated for the fresh and completely dried leaves. 



Fresh leaves. Air-dried. Dried 

 at 100° 



Water 60.0% 9.6% — 



Crude ash 1.7 3.8 4.2% 



Extd. by solvents 12-9 29.2 32.3 



Insol. residue 25.4 57.4 63.5 



