BOTANICAL GAZETTE. 21^1 



ly or asexiially, the mode of reproduction depending more especially 

 upon the external conditions. 



Speaking generally, it is not possible to say of a ^pore of any given 

 Thallophyte that the product of its germination will necessarily be a 

 sexual plant, nor is it possible to say of the oospore that the product 

 of its germination will be necessarily an asexual plant. 



The results of the discussion are .summed up as follows : — It appears 

 that it is impossible to detect any distinct alternation of generations 

 in the life-histories of Thallophytes. with the exception of the Coleo- 

 cJurtfc and the Characcfv. — A. R Morgan. 



Melanthium ViRGiNicuM. — Seeing Mr. Broadhead's notice of the 

 above species I would like to give my observation about it. 1 found 

 this beautiful plant hrst in 1874, on a piece of woodland where the 

 underbrush was very small, along with Stenanthiuvr angusf/ifolium. 

 But as soon as the underbrush grew higher it was nearly gone. This 

 year upon another piece oi" woodland, where I had before only once 

 found a few specimens, the bushes had been burned, and I found 

 Melanthium. YirginicuDi in great abundance. It also grows abund- 

 antly on the Missouri Pacific Railroad, between here and Kirkwood. 

 It is evident that the plant likes air and light. If the light is ex 

 eluded, the bulbs simply remain in the ground and do not grow. — 



li. IiIggert, »S7. Loiiis^ Mo. 



The Genera Plantaru.^i of Bentham and Hooker. —The first part 

 of the third and concluding volume of this important work — to com- 

 prise the remaining Dicotyledonous orders — is now in press, and will 

 be published in London at the close of the year. It is convenient 

 and may not be improper to announce in the Botanical Gazette, 

 that most of the botanists of the United States who possess this in- 

 dispensable work thus far have procured it through the mediation of 

 the subscriber, who, in view of the number of copies thus taken is 

 supplied at a considerable discount, the whole advantage of which 

 inures to the recipient. The two volumes already completed are 

 pul)lished at £5, 6, 0. The price charged the subscriber is £4, 8, 0. 

 The new part will be furnished at a similar discount. Botanists w^ho 

 have in this way obtained the published parts, and who wish to re- 

 ceive the remainder through the same channel, are requested to com- 

 municate their wishes in this respect, without delay, to The Curator 

 of the Herbarium of Harvard University, Cam])ridge, Mass, — 



Asa Gray. 



