718 BIOGRAPHICAL SKETCH OF HENRY MILNE-EDWARDS. 



Between tlie years of 1826 and 1845 the history of mollusks, and 

 especially that of ascidiaus, equally owe important contributions to 

 Milne-Edwards. He particularly observed the circulation of these 

 animals, which is more perfect and better developed than that of insects, 

 and exhibits in some cases a remarkable i)ecu]iarity. Their blood 

 does not only flow in vessels with partitions strictly limited by special 

 membranes, but continues to flow on into a system of openings placed 

 between the different organs in which the alimentary juices mingle 

 directly with the mass of nutritive fluid. De Quatrefages pursued 

 the same system of observations in works which it is not my present 

 province to criticise with respect to their individual character and 

 originality. A great discussion speedily took place between Tere- 

 boullet and other learned men on the question of " phlebenterism," 

 the name Quatrefages gave to his discovery, and the result was impor- 

 tant modiflcations in the theories accepted up to that time as to the 

 true character of the circulation and nutrition of the lower animals. 



Zoophytes could not escape the new method inaugurated by the 

 investigation of marine organisms. After starting with experiments 

 on polyps, sea nmts, and s^tonges, Milne Edwards resumed his studies 

 more thoroughly in 1833, 1835, and 1837. He first examined jelly-fish, 

 hitherto regarded as a sort of gelatinous, nearly amorphous mass; in 

 reality, their structure is one of the most complicated, their translu- 

 cense preventing, at first sight at least, the multiplied details of tlieir 

 organization from being distinguished. 



In his investigations of alcyouaria on the coast of Algiers this learned 

 naturalist made apparent the singular structure of those ])olypiers, 

 which contain both tlie organs l)elongingto the young individuals that 

 are placed at the terminal surface and the collective organs which 

 exist only for the benefit of the community, but communicate with 

 the digestive centers of the individuals in such a manner that all profit 

 by the nourishment absorbed by each, thus establishing a common 

 circulatory system between the individuals of one colony. So diverse 

 are modes of life that it is diflicult to assign varied organizations to one 

 systematic fonnula. By his studies of the anatomy of coral in 1838, 

 and above all by his observations of the nature of coral reefs, Milne- 

 Edwards paved the way for the admirable works which were the 

 foundation of the reputation of our colleague, Lacaze-Duthiers. 



But I must pause in this long enumeration of the special labors of 

 Milne-Edwards to take them up as a whole, to analyze them, and show 

 their historical share and importance in the development of the nat- 

 ural sciences; for this a longer time would be required than 1 have 

 at my disposal to-day, and, I do not hesitate to say, a voice having more 

 authority. However I can not pass by in silence two books which 

 attracted the attention of their time by. reason of entirely distinct 

 claims. I will speak first of the works relating to the production of bees- 

 wax. A great dispute had arisen between agricultural chemists about 



