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A STUDY OF THE LEAF-ANATOMY OF SOME NATIVE 

 SPECIES OF THE GENUS ANDROPOGOX. 



[N.O. GRAMINK.E.] 



By E. Breakwkll, B.A., B.Sc. 

 (Plates xxix. xxxiii.) 



The microscopic anatomical examination of the leaves of some 

 native species of the genus Andrapogon, as discussed in the fol- 

 lowing pages, was made for two purposes. Firstly, to investigate 

 any similarities or differences that may exist in the general and 

 detailed internal structure of the leaves of different species; and, 

 secondly, to investigate any oecological characteristics in the 

 structure of the leaf, which may be associated with, and accom- 

 pany, the general habit and habitat of the plant in question. 



The method adopted, in preparing the sections, was briefly as 

 follows. The fresh leaves, in small pieces, were fixed in picro- 

 acetic acid. Great difficulty was at first experienced in elimin- 

 ating the siliceous elements from the leaves; but, eventually, a 

 successful method was found in soaking them, for some consider- 

 able time, ranging from 8 to 12 hours, in a 50 per cent, solution 

 of hydrofluoric acid and water. 



The embedding, cutting, staining, and mounting were per- 

 formed by Mr. W, A, Birmingham, of the Biological Branch of 

 the Department of Agriculture, to whom I am much indebted for 

 the really excellent manner in which he prepared the specimens. 

 My thanks are also due to Mr. G. P. Darnell Smith, B.Sc, F.I.C., 

 F.C.S., Biologist, for his courtesy, and for permission to use the 

 biological apparatus. The stains used were haematoxylin and 

 erythrosin. It was found necessary to decolourise after staining 

 in haematoxylin. These two stains appear to give a fairly good 



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