446 BOTANICAL GAZETTE [| DECEMBER 
Finding that, just as in muscle and nerve, the nitella cell may be stimu- 
lated by the production of katelectrotonus and the disappearance of anelec- 
trotonus and that the stimulation wave is accompanied by the so-called 
“negative” wave, he concludes that muscle, nerve, and nitella cell must have 
some fundamental structural element in common. As the nerve has only 
conductivity he concludes that conductivity and contractility are properties 
of different substance. The conductive plasma, existing alone in the nerve, 
is accompanied in muscle and nitella cell by another substance, which con- 
ditions the phenomena of contraction and streaming. Nor has he over- 
looked the difference between muscle and nitella, in that a stimulus in the 
one case causes a resting organ to work, while in the other it brings a work- 
ing organ to rest. 
The explanation of this is to be found only in a fundamental difference in 
the structure of the mechanism of movement. The details of the discussion 
must be sought in the work itself.—C. R. B 
R. P. Sypow has brought together much useful information in a botani- 
cal calendar.7?7 Besides the astronomical calendar, there is a calendar for 
notes and memoranda for each day, with the birth and death days of many 
distinguished botanists; tables of equivalents in money, weights, and 
measures; post and telegraph rates; the Berlin rules for nomenclature; a 
list of the cryptogamic exsiccate which have been issued; a list of the 
botanic gardens and museums; and finally a list of the botanical collections to 
be found in the larger museums and herbaria. The difficulty of securing 
accuracy and completeness in the last three lists is very great. The author 
realizes that it has not been attained and appeals for assistance by correc- 
tions.—C. R. B. 
A VERY USEFUL ACCOUNT of the economic grasses, by F. Lamson- 
Scribner, has been published as Bulletin 14 of the grass and forage investiga- 
tions of the Division of Agrostology, ex eae of Agriculture. Brie 
descriptions and illustrations are given the more important economic 
grasses of this country, or those which re: been introduced because possess- 
ing some merit. Bulletin 15 of the same division isa report upon the forage 
plants and forage resources of the Gulf states, by S. M. Tracy, containing 
descriptions, comments, and illustrations, in addition to the general discus- 
sion of the forage problems of the south J. M. 
- H. KNowLTon has done Riccaine great service in the preparation of 
his Catalogue of the Cretaceous and Ti ertiary plants of North America.” € 
*7 Sypow. P.—Deutscher Botaniker-Kalender fiir 1899. 16mo. pp. 198. Berlin: 
a Bomtsger 1898. 3. 
*® KNowLTon, F, H.—Bulletin of the U.S. godin Survey no. 152. pp. 1-247- 
Washington, 1898. 20 cents, 
