; 1887] Botany. 769 
_ Where it is not possible to devote more school time to this: sci- 
ence, let the teacher arrange for a year’s course with but one or 
_ two exercises each week. A pupil who devotes two exercises 
each week throughout one school year to botany will at the end 
7 of that time have a much better and far more enduring knowl- 
_ edge of the subject than if he had devoted five exercises each 
= week to it for a single term. Properly managed, even one exer- 
qse each week for a year will bring better results than five exer- 
= cisesa week for one term. Two exercises each week in the fall 
_ term, one each week in the winter term, and two a week in the 
_ Spring term is an arrangement which I have found to work 
-excellently in practice —Charles E. Bessey. 
| 
A + . . f 
3 Botanical News.—Sereno Watson’s contributions to American 
i d Botany, XIV., 
Arts 
S ree new genera are described,—viz., 
Asclepiadaceæ)}, Prochuyanthes (Agavee), and 
(Umbellifere). The determinations of the Gamopet- 
Key hort papers before the Academy of Natural Sci- 
line Philadelphia upon the following subjects,—viz., “On 
sig of the Naturauisr reaches its readers the long- 
is W, F resh-Water Algæ of the United States,” by Rev. 
Wolle, will be ready for distribution. It will appear in 
aot ` first consisting of three hundred and sixty-four 
10. 8, ss 
