BOTANICAL PEN-PORTRAITS 
209 
and very carefully worked up. Each drawing is accompanied by a 
scale from which its dimensions can be readily obtained, but no indi¬ 
cation of the corresponding magnification expressed in diameters is 
given. This is to be regretted, since drawings can be compared more 
readily by noting the magnification in diameters than by the use of 
scales, and the reader also quickly obtains an idea of the combination 
of lenses needed to produce a result similar to that figured. A 
further improvement to the legends would be made were the letters 
and abbreviations printed in a type differing clearly from that used 
for the explanations following them. 
With the general proposition of the authors that “ it is impossible 
to make real improvements in the art of drawing for botanical pur¬ 
poses,” that “ the figures in the works of Dodomeus and Fuchs are 
vastly superior to any product of the present age,” and that “ the 
ancient Egyptian artists would have even surpassed them,” one 
cannot possibly agree. One feels, however, that description of 
microscopical structure in the past has not been as complete or as 
systematic as it might have been, and Pen-Portraits will do good by 
calling attention to this defect and by suggesting methods of descrip¬ 
tion which are applicable to this type of work. As pointed out in 
the volume itself, such systematic description of a more limited 
character has already been freely used by previous authors, such as 
Gamble (1902) and Stone (1904) in their books describing com¬ 
mercial timbers and by Koch in bis j Die mikroskopisclie Analyse der 
Progenpulver and Pharmakognostischer Atlas. Drs. Moll and 
Janssonius claim to have made an advance upon these by introducing 
a “ perspective, description,” which combines in one statement the 
particulars obtained by the study of sections in three directions at 
light angles to one another. In the opinion of the authors, there is 
thus put before the reader sufficient detail to enable him to build up 
a mental picture of the cells, tissues, and organs as solid structures. 
In doing this, “the physical energy of the student is” undoubtedly 
“ taxed rather heavily,” and, although the descriptions form a very 
useful method of recording facts, one can hardly share the view of 
the authors that “ it tends to make pictures more and more super¬ 
fluous.” On the contrary, one feels, after reading these elaborate 
descriptions, that they need to be supplemented by good detailed 
drawings before one can form an accurate idea of the structures 
described. The descriptions serve to draw attention to all essential 
details and to emphasise diagnostic characters, but cannot be con¬ 
sidered as being complete in themselves apart from illustrative 
drawings. 
One feels also some doubt as to the precise value of the dimen¬ 
sions given for the various cells. It requires a study of a very large 
range of specimens before one can lay down maxima and minima for 
the sizes of all the cells concerned; and, although the numbers given 
may accurately record the dimensions observed, in one or a few 
preparations, it would be unwise to accept them as criteria for the 
exclusion of material as foreign or as sophisticated. For example, 
