38 Recent Literature. (January, 
be hoped, do much towards correcting this misconception of the true spirit 
of botany. In the text-book before us only 160 pages are devoted to 
phanerogams, while the part relating to cryptogams fills 213 pages, and 
that to physiology a still greater number of pages; so that the reader 
cannot fail to draw the conclusion that what many botanical students in 
this country have been in the habit of regarding as the most important 
thing, is only one branch of the science, and by no means more impor- 
tant than others. Even in that part of the text-book relating to phane- 
rogams there are many ways of looking at familiar subjects which will be 
new to American botanists, as, for example, the theory of the carpel, and 
we cannot fail to see that, after all, some things which we have come to 
regard as facts are nothing but plausible theories, and that other people 
may have different but equally good theories. 
In the fourth edition of the Lehrbuch is a classification of Thallophytes 
which is given as an appendix to the translation. Sachs rejects the old 
division into algæ, fungi, and lichens, and, instead, gives a series of paral- 
lel groups, those, on one hand, containing chlorophyll and those, on the 
other, free from chlorophyll. The existence of parallel groups in alge 
and fungi has long been known, but we believe this is the first general 
text-book in which the division into alge and fungi has been abandoned. 
Although in a general way correct, the details of Sachs’s classification 
cannot be accepted. Although Sachs is preéminently a physiologist, it 
seems to us that he has been quite as successful in his presentation of the 
researches of others in anatomy and cryptogamy, as of his own researches 
in physiology. We are not made very much wiser by being told that 
many motions arise from the tension of tissues, and it seems as though the 
term reiz, which may mean either irritation or some inherent attractive 
force, were only a learned way of concealing ignorance. Throughout the 
book we are impressed with the fact that advance in botany during later 
times has been dependent on the use of the compound microscope. Here- 
after it will be as impossible for a botanist to keep up with the times 
without doing microscopic work as for an astronomer to succeed without 
a telescope. 
It is to be regretted that the price of the translation is so high, but the 
number and quality of the illustrations probably render it necessary. 
It would be at least a consolation to American purchasers to know ex- 
actly what the price is, or ought to be, in this country. We imported the 
book directly by mail and were obliged to pay $8.60; others have been 
charged as high as $12, and one, more fortunate, procured a copy at a 
book store for $8. It has been suggested that the work be divided 
into parts to be sold separately, and, although students should not 
read one part to the exclusion of others, many would be able to purchase 
the separate parts at different times who could not afford to buy the 
whole at once. An abstract of the translation corresponding to Prantl’s 
abridgment of the German would hardly be advisable, but a translation 
of Thomé’s Lehrbuch der Botanik, would be preferable. 
