1901] CURRENT LITERATURE 427 
preparation of a handy manual which presents it, provided, of course, that 
this same manual makes it possible for the great host of amateurs to deter- 
mine their plants with satisfaction. 
Concerning the other features of this JZanuad there can be no real dis- 
cussion. The Engler and Prantl sequence is a matter of course, and is not 
under discussion as contrasted with that used in Gray’s M/anua/. The use of 
the metric system is another well approved step which calls for no special 
comment, except that our manuals have been too slow in adopting it. 
As to the work of the publishers, it deserves very high praise. Thin but 
tough paper, clear type, and narrow margins, so that a book of over 1000 
pages can be carried in a good-sized pocket and can be bought for $2.25 isa 
triumph of the publisher’s art and common sense.—J. M. C. 
MINOR NOTICES. 
A MONOGRAPH of the North American Sordariaceae has been published 
by David Griffiths.2 After a general discussion of distribution, methods, 
development, and spore dissemination, the six genera are presented as fol- 
lows: Sordaria (13 spp., 5 new), Pleurage (31 spp., 13 new), Hypocopra (9 
SPpp., 3 new), Delitschia (9 spp., 5 new), Sporermia (15 spp., 7 new), and 
Sporormiella (1 sp.). Material from over 20 states was studied, and the 
period of development of many of the species determined.—J. M. C 
ARTHUR H. CuuRcH has begun the publication of studies “On the rela- 
tion of phyllotaxis to mechanical laws.’’ The first part 7 now before us deals 
with construction by orthogonal trajectories. A general historical discussion 
of phyllotaxy is followed by a record of observations accompanied by hand- 
Some half-tone illustrations representing chiefly high orthostichies. This is 
followed by discussions of the geometrical representation of growth, the 
application of spiral-vortex construction, ideal angles, and asymmetry.— 
M,C. 
THE FouRTH PART of Engler’s Pflanzenreich has appeared, and con- 
tains the Monimiaceae (family 1o1 of the spermatophyte series) by Janet 
Perkins and Ernst Gilg. After the usual discussion of the important struc- 
tural features of the family, and its geographic distribution, there follows the 
Systematic presentation. Thirty-one genera are recognized, six of which 
ave been established heretofore by Miss Perkins. The species are 253 i 
number, by far Soe largest genera being Siparuna (89 spp.) and st ae 
(71 spp.).— J. M. C. 
—— Torr. Bot. Club 11: 1-134. pés. 2-79. IQOI. 
uRCH, A. H.: On the relation of phyllotaxis to mechanical laws. Part I. 
Contin of orthogonal trajectories. pp. 38. #gs. 34. Oxford: Williams and 
Norg 1901. 3s. 6d. 
