4 6 
A Voice from the Past. 
The last chapter of the work is devoted to a consideration of 
the technique of phycological investigation. Research-stations, 
methods of capture and transport are dealt with, and there is a 
very useful section on the culture of algae, in which methods 
the author has himself used with success are described. 
In concluding this somewhat lengthy review, in which an attempt 
has been made to give the reader some idea of the contents of 
Professor Oltmanns* comprehensive work, we may reiterate the 
opinion that those generalisations, occurring particularly in the 
earlier part of the present volume, which refer to particular groups, 
would have been better included in the Special Part. This would 
have rendered the treatment of the different groups more complete 
and interesting, and would have allowed of more general summaries 
in the present part. The other general remark which we have to 
make is to express regret that Professor Oltmanns has not attempted 
a synthetic treatment, and particularly an evolutionary treatment, 
of his subject matter in a greater number of cases. We feel sure 
this could be done with success in many instances, and such treat¬ 
ment is of the highest value when undertaken by such a master of 
his subject as the author of this work. The amount of information 
contained in its 1100 odd pages, and the skill displayed in its 
arrangement and detailed discussion is most striking, and we must 
warmly congratulate Professor Oltmanns on having brought to a 
conclusion this magnificent compendium of existing knowledge 
of one of the most fascinating and important groups of the plant 
kingdom. A.G.T. 
A VOICE FROM THE PAST. 
rr\HE morphologist of to-day who concerns himself with the 
]_ relations of the great groups of plants is probably grateful to 
Hofmeister and other contemporary workers who elucidated the 
ground plan of their life histories. Hut if he penetrates to an 
earlier date and dips into the pre-Hofmeisterian literature he seems 
to move in a strangely unfamiliar world, in which the ordinary 
landmarks of the phylogenetic morphologist are hardly discernible. 
For the mystery of the double generation, which involves all 
the classes of plants from the Liverworts onwards, was still 
unprobed, and the whole series was regarded from the stand-point 
of the flowering plant—a thing ol one generation that bore sexual 
organs. 
The gametophyte of the fern, or prothallus, was the homologue 
of a cotyledon, and so it remained till it occurred to Suminsky 
(1845) that this was a special stage set aside for the production of 
the sexual organs. 
But notwithstanding this serious limitation, at least one 
Botanist proved capable of a broatl philosophic outlook on the 
