1899] . ; CURRENT LITERATURE I41 
each genus and species and of each author mentioned. The Bavarian 
Academy of Sciences, which has assisted in its publication, might well have 
increased its subvention if necessary to provide such an index.—C., R. B. 
Speculative biology. 
In 1875 Pfliiger propounded a hypothesis regarding the constitution of 
organized bodies which may be described as the hypothesis of chemical con- 
tinuity. Impressed with the extensive polymerization among carbon com- 
pounds, especially the proteids, he ventured the suggestion that in an organism 
polymerization may progress indefnitely, so that the whole protoplasm is not 
an aggregate of similar molecules having definite molecular weight but may 
form a single giant chemical molecule. This theory has found few adherents. 
It is accepted in toto, however, by Dr. Georg Hérmann, who proceeds in a 
recent book? to show its adequacy to explain certain biological problems, 
and, therefore, its inherent probability. 
He applies it to the transmission of the impulse in nerve and the phe- 
nomena of nerve section; to the contraction of muscle and the discharge 
from the electric organs of fishes; and discusses the structure of the cell and 
- Gitepra of the protoplasm “ from the standpoint of the principle of chem- 
‘cal continuity,” (Hypothesis — principle: are they synonymous?) 
ro aa the book is pure speculation, and must not be taken as anything 
hick oe fs fear me author does not always remember the sandy founda- 
diss oe as sie building. The various ingenious diagrams, sepreeeptDe 
whieh os Ivers interesting forms and positions lend an air of verisimilitude 
ch might deceive the very elect. 
sled vag as necessary ; speculation is indispensable in the 
srrioksis AN naa hypotheses by the investigator ; but it may . 
while. Until ae whether the publication of a speculation is ever wort 
speculation of . me more intimate knowledge of the chemistry of proteids, 
*aoity init vi, e kind here set forth must be regarded as little more than 
: ation of spirit—_C. R. B é 
ae NOTES FOR STUDENTS. 
St ote his observations on the agencies by which insects are 
“alviq a paabile Professor J. Plateau now gives a large number made on 
ment that the oi on Hydrangea opuloides,* confirming his previous state- 
aS Y are chiefly attracted by the sense of sight. Neither the col- 
ORMANN, Grorc 
der lebenden s : Die Kontinuitat der Atomverkettung ein Strukturp’ sone 
Aa ubstanz. 8yo. pp. iv-+118. figs. 32. Jena: Gustav Fischer. 1899. 7 
*Mém, 
Soc. Zool, de France 11 : 339-375. fig. 4. 1808. 
