400 BOTANICAL GAZETTE | MAY 
Sydow,3 with some assistance from P. A. Saccardo, G. Lindau, and P. Hen- 
nings, to whom ‘acknowledgment is made in the preface. The work is 
brought down to the end of the year 1897. 
The type is good, and the spacing ample, so that the volume can be con- 
sulted with readiness and comfort. The host species are arranged in asingle 
alphabet, following the authority of the Zadex Kewensis, with the fungi asso- 
ciated with each species named immediately beneath. 
The attempt has been made to use but one name for each species of host 
and of fungus, thus omitting synonyms. The imperfections in the literature 
of the fungi have made it especially difficult to follow out the plan with the 
desired success. It is easy to point out names that should have been omitted, 
as they are clearly synonyms, and to mention others that should have been 
included. But such shortcomings are incident to the subject, and only 
emphasize the necessity for early monographic work, 
To anyone determining parasitic fungi the volume will prove of the greatest 
service, and, in connection with the descriptive part of the great Sy/oge, 
will be especially welcome.—-J. C. A 
‘ What is ‘‘ vital energy? ”’ 
THE PROBLEM before the physiologist is the nature of living matter. 
Anything that contributes to a solution of this problem is welcome. Dr. Oscar 
Loew has already done much to make possible a better understanding of the 
chemistry of protoplasm and its products. In a work published in London in 
1896 entitled The energy of living protoplasm, he set forthin English the views 
which now find a more complete exposition in German under the title, The 
chemical energy of living cells4 As the former work was not received by the 
GAZETTE for review, a somewhat extended résumé of his views may now be 
useful. 
After giving a historical summary of previous views as to the <a 
of vital activity, he avers that the primum movens of the living cell 1s to be 
sought neither in heat nor electricity, but in a specific chemical activity, Viz. 
the assumption of oxygen by the living substance. The main question, then 
is, “ What conditions lead to the activity of cell respiration and to the miu 8 
formation of the heat thereby produced into the chemical energy of the living 
cells 2.” ons 
The living protoplasm, “at once artificer, work-shop, and plastic material, 
3SyDow, P.— Sylloge fungorum omnium hucusque cognitorum digessit P. a 
Saccardo, Vol. XIII; Index universalis et locupletissimus nominum pone 
hospitum specierumque omnium fungorum has incolentium quz usque eM rey 
1897 innotuerunt. Roy. 8vo, pp. vi+ 1340. Berolini: Fratres Borntraeger, I 
‘Loew, Oscar: Die chemische Energie der lebenden Zellen. 8vo. pp- *#-T 
175- Miinchen: Dr. E. Wolff. 1899. Af 5; geb. Af 6. 
