218 AUSTRALIAN NATIVE PLANTS. 
tried. He gives the results of several qualitative experiments with 
them. 
Western Australia (JZ. Frasert); New South Wales 
(MM. Miquellz). 
28. Macrozamia Perowskiana, 1777., (Syn. 12. Denisoniz, F.v.M. ; 
Lepidozamia Perowskiana, Regel. ; Encephalartos Denisonit, 
F.v.M.); N.O., Cycadez, B.FI., vi., 253. mcephalartos 
Denisoniz in Muelil. Cens., p. 110. 
A small quantity of gum of this species has been received at 
the Technological Museum, and apparently much resembles that 
experimented upon by Mr. Blackett. It is in flattened pieces, 
reminding one strongly of ‘button lac,’ but much lighter in 
colour even than the “fine button lac”? of commerce. The 
flattened shape is due tothe mode of collecting it. A spontaneous 
flow of gum does not appear to occur in any species, but from the 
cut ends of the cones and bases of leaves it exudes more or less 
freely. If put to drain on a plate, the flattened shapes of “ button 
lac’”’ will be very readily obtained. If one of these flattened pieces 
be placed in water, it begins to swell immediately, and this 
absorption of water goes on for several days, by the end of which 
period it has swelled to about fifty times its original size. It then 
presents the appearance of an almost colourless, quivering jelly. 
This jelly assumes a pseudo-crystalline appearance, forming 
angular masses. ‘This result is, of course, in consequence of the 
minute fissures in the dried gum. It breaks readily, has a bright 
fracture, and in the mouth feels somewhat like tragacanth. 
New South Wales and Queensland. 
29. Macrozamia spiralis, /77., (Syn. Zamia spiralis, R.Br., 
partly; Zcephalartos spiralis, Lehm.); N.O., Cycadez, 
B.FI., vi., 251. L£ncephalartos spiralis, Lehm., in Muell. 
Cens., p., 110. 
“ Burrawang.” 
This is another species, the gum of which the author has 
collected. He has no doubt that the proximate analysis of each will 
be found to give closely-agreeing results. A few days after the 
plants have been mutilated, as already described, the dried gum may 
