190 THE JOURNAL OF BOTANY 



different " algae " as Cystococais, Trentepohlia, Stigonema, and 

 Nostoc. He allows that those gonidia increase by division within 

 the thallus after they have been formed by the hyphae, and that 

 they also may live a free life in the open as " algae." 



Elfving's view lands us in a series of problems : how are we 

 to account for the origin of other algae that do not enter into 

 symbiosis with the lichen fungus, but the life-histories of which are 

 entirely comparable with that of gonidia in a free condition, unless, 

 as he seems to hint, the ancestors of those algae are to be found 

 among lichen gonidia ? Again, how explain the twofold repro- 

 ductive system combined in one plant — the fungal and the algal ; 

 each after its kind '? It is easier to suppose wrong observations 

 as to the genetic connection of the colourless and the coloured 

 cells, than to accept the conclusion that a homogeneous plant 

 should exactly follow the life-history of two different groups of 

 plants, and of various sections within that group. The author does 

 not attempt to explain these anomalies ; he is content to affirm and 



reaffirm the correctness of his own observations. a t o 



A. Li. b. 



BOOK-NOTES, NEWS, dc 



It has required large type, wide leading, and broad margins to 

 extend to less than a hundred small pages Dr. William Macdonald's 

 reprinted papers on Makers of Modern Agriculture (Macmillan). 

 The "makers" are Jethro Tull (1674-1740), Thomas William 

 Coke—" Coke of Norfolk "—(1752-1842), Arthur Young (1741- 

 1820), Sir John Sinclair (1754-1835) and Cyrus H. McCor- 

 mick (1809-1884) — the last a Virginian, " the inventor of the 

 reaper" — i.e. the reaping machine. The sketches betray evi- 

 dence throughout of their newspaper origin ; thus the notice of 

 McCormick begins : — " It is hardly to be expected that those 

 people who devoutly chant in a million churches the fourth 

 sentence of the Lord's Prayer should think with gratitude of any 

 other person than the Divine Giver of all Good. Yet it is strange 

 to reflect that, although every schoolboy knows something of the 

 life of our least Poet Laureate, not one in ten thousand could tell 

 you the career of the man who responded in a truly miraculous 

 manner to the heartfelt, world-voiced matin of both rich and poor, 

 ' Give us this day our daily bi'ead.' " The knowledge which Macaulay 

 ascribed to his schoolboy pales before that which Dr. Macdonald 

 postulates for his. The " subsequent paper," promised on p. 52, 

 does not appear : it was to deal with the writings of Young, of 

 which Dr. Macdonald says : " Our library is far from complete, 

 yet we possess sixty-six volumes of his sparkling prose, which 

 placed one upon another attain a height of nine feet — a monu- 

 ment of amazing industry .... He met and conversed with the 

 greatest savants of the age, yet his mind never burst the old wine 

 bottles which he served out in the Sussex store." " Spai'kling 

 prose" of this kind adorns the little book throughout, but we 

 cannot help thinking it is dear at half-a-crown net. 



