1839.] Linnean Societij. 11 



laginous substance, not coloured by iodine, and a small quantity of 

 the grains of starch, lying in the usual manner in the parenchyma 

 which surround the nodules, and readily susceptible to the usual ac- 

 tion of iodine. The tubercles of many South-African Ophrydec^ pre- 

 sent when dried the appearance of bags filled with small pebbles, as 

 if the epidermis had contracted over hard bodies in the inside. If a 

 fresh root of Satyrium pallidum be divided transversely the cause of 

 this appearance is explained, for with its soft parenchyma are mixed 

 tough nodules, clear as water, and often twenty times as large as the 

 cells which surround them. These nodules are easily separable, are 

 tough like horn, and on being sliced appear to be perfectly homo- 

 geneous. They are scarcely soluble in cold water; when boiled they 

 become tumid and partially dissolve into a transparent jelly. If ex- 

 posed to the air they rapidly dry and become brown. The aqueous 

 solution of iodine has no sensible effect upon them in their natural 

 state. 



On charring shces of some salep procured at Covent Garden, a 

 coarse preparation of wild Ophrydeee, the author found that the no- 

 dules apparently homogeneous were composed of extremely minute 

 transparent cells, filled, as he supposed, with a secretion of the same 

 refractive power as themselves, and adhering naturally to each other 

 firmly ; the double walls of the cells and intercelliilar spaces being 

 only made apparent by the charring process. The author explains 

 the error of those who have considered salep to consist chiefly of 

 starch, by allusion to the mode of its preparation. The tubercles 

 are first parboiled and then dried, the effect of which is to dissolve 

 what starch exists in the cells surrounding the nodules. The dis- 

 solved starch flows over the surface of the nodules, from which when 

 dried it is undistinguishable, and consequently when iodine is ap- 

 plied to salep the mass appears to become iodide of starch. If the 

 nodules, however, after this action of iodine, be removed, they are 

 seen to retain their original vitreous lustre. 



The author remarks that these nodules of Ophrydece are, as far as 

 his observations extend, absent in the tubercles of the other tribes 

 of Orchidacece. 



Read, a paper entitled " Some Data towards a Botanical Geogra- 

 phy of New Holland." By Dr. John Lhotsky, late of the Civil Ser- 

 vice, Van Diemen's Land. Communicated by Prof. Don, Libr. L.S.. 



The author commences his paper with the observation, that it was 

 the lot of Mr. Brown to become connected in an almost exclusive 

 way with the Flora of New Holland, he having been the first to illus- 



