318 ' BOTANICAL GAZETTE [OCTOBER 
maintaining that the results were modified by the gaseous impurities of the 
laboratory in which they were obtained. GUTTENBERG,’° on repeating his 
experiments in pure air, finds essentially the same compensatory values of 
light as he found in his earlier work. GuTTENBERG used the seedlings of 
Avena and Brassica, forms much less sensitive to impurities than are legumes, 
with which RIcHTER worked. GUTTENBERG finds in Vicia sativa, contrary to 
RicHTER, that laboratory air does not increase the heliotropic sensitiveness, 
but in agreement with Ricurer he finds the geotropic irritability lessened. 
On this point, GUTTENBERG’s experiments are much more critical than RIcH- 
TER’S.—WILLIAM CROCKER. 
Morphology of Phylloglossum.—A recent paper by WERNHAM™ represent, 
a type, at the moment becoming much too common, in which a small basis of 
imperfectly examined facts is made to serve for large conclusions which are 
neither clearly nor logically drawn. The author has examined by means of 
serial sections the anatomy of two specimens of Phylloglossum Drummondii. 
He concludes that the basal leaves of this species (the protophylls of certain 
authors) are microphyllous, although superficially relatively large in sizes 
because their traces leave the stele without leaving any gap, as is the case with 
the Lycopsida. Concerning the relation of the sporophyll traces to the vascu- 
lar system of the axis, the account is very obscure, since it is not made clear 
whether gaps are or are not present.. The most remarkable feature of the 
article is the interpretation of the larger strand which passes off from the 
crown of the functional tuber toward the tuber of the succeeding year as 4 
leaf trace. It has been regarded by other observers, apparently with good 
reason, as a branch supply, and the present author adduces apparently no yalid 
evidence why this view of its nature should not continue to be held. On the 
basis of this imaginative interpretation, he comes to the conclusion that 
Phylloglossum was originally a megaphyllous form, which has become much 
reduced. It would be possible to prove almost anything with such reasoning 
as this. It seems highly desirable that morphologists should avoid eccentric 
conclusions of the nature illustrated by the article here reviewed. Obviously, 
conclusions of permanent value in regard to leaves or other organs can 
reached only in the case where there is no room for doubt as to the morpho- 
logical category of the structure under discussion.—E. C. JEFFREY. 
Classification of conifers.—A new classification of conifers, based ar 
morphology, geographical distribution, and geological history, is Propos® 
x0 GuTTENBERG, H. R. v., Ueber das Zusammenwirken von Geotropismus und 
Heliotropismus und die tropistische Empfindlichkeit in reiner und unreiner “as 
Jahrb. Wiss. Bot. 37:467-492. 1910. 
tt WeRNHAM, H. F., The morphology of Phylloglossum Drummondii. Annals of 
Botany 24:335-347. figs. 8. r9to. 
