308 
the bacillar-corpuscles, of the segment organs, of the true 
blood- corpuscles of the vascular fluid. It is rarely that one 
man contributes so much to the knowledge of a group 
(and so accurately, and trustworthily too) as Professor 
Claparede has here done. His work is not only a necessary 
guide to all engaged in the study of Annelids, but is a grand 
model of that excellence after which all naturalists should, 
however vainly, strive. Having a complete knowledge of 
the works of his contemporaries, he does not fail to give them 
their just due, whilst his great skill in observation and deli- 
neation enable him to correct their mistakes and to add new 
facts to the store of science. He does not permit his imagina- 
tion to get the better of his reason, and his sound judgment 
does not allow him to misinterpret facts ; lastly, he commu- 
nicates the result of his researches in unaffected, pointed, 
and interesting language, which is quite free from the taint of 
egotism or pedantry. 
