50 SELECTED NOTES FROM 



the coil winding from right to left. Linnaeus would suppose the 

 observer to be inside the coil, when it would wind from left 

 to right. 



H. Basevi. 



This plant is one of a large genus of tropical Orchids 

 inhabiting the warmer parts of Asia. They have distichous 

 leaves, mostly channelled and unequally truncate, but sometimes 

 terete. It is curious that the flowers are of all tints except blue; 

 some are very fragrant. 



E. E. Jarrett. 



Nostoc, when growing, has the appearance of an olive-green, and 

 dark jelly-like substance in folded or plaited masses. Under high 

 power (J-in. o.g.) it appears as strings of cells, like rows of beads, 

 with, here and there, larger cells — these are called " heterocysts." 

 The threads of cells are enclosed in gelatinous sheaths, which 

 melt together, so that large colonies are the result. 



P. L. Smith. 



I am inclined to think that the above statement as to the 

 " gelatinous sheaths melting together so that large colonies are 

 the result/' not strictly correct. Berkeley, at p. 139, gives descrip- 

 tion of Nostochiiiea as follows : — " Threads very slender, 

 moniliform, invested with gelatine, which is at length to all 

 appearaiice common to the mass, but at first apportioned to each 

 individual thread \ propagation by the division of the threads or 

 by zoospores." 



The editors of the Micro-Dictionary are evidently of Mr. 

 Smith's opinion. Under this head they remark, " the amorphous 

 matrix is produced by the fusion of the special gelatinous sheaths 

 of the individual filaments." I myself incline to beUeve this is 

 only in appeara?ice. Nostoc is the typical genus of the Nostoch- 

 ifiea; the species are very numerous, and are usually found on 

 damp ground, wet rocks, mosses, etc. All are characterised by 

 the necklace of spores, surrounded for the most part with firm 

 and copious jelly ; some joints are larger than the rest — they 

 increase by the threads breaking up into fragments, bursting 

 through their common envelope and becoming dispersed in the 

 water; now they have spontaneous motion which soon ceases. 

 Here fragmentary threads divide longitudinally and transversely, at 

 last constituting bundles of new threads. The larger joints in the 



