174 Observations upon the Fossil Polypi of 



ber we now proceed to describe, will almost double the total 

 amount of the species already discovered in all the other marine 

 deposits of the crust of the globe. 



Many fossil Escharae differ greatly from the species now 

 existing, whilst others, on the contrary, very much resemble 

 them ; but up to the present moment we have not been able to 

 establish the specific identity of any one of these polypidoms 

 with the recent species ; and it is therefore probable that the 

 polypi of this genus, which inhabited the ancient seas, were 

 all destroyed previous to the creation of those which are ex- 

 isting at the present time. 



The concluding portion of the memoir is occupied with the 

 description of eighteen species, seventeen of which, according 

 to M. Edwards, are entirely new. 



At the next meeting of the Academy, on Monday the 28th 

 of November, M. Dujardin presented a communication, of which 

 we give the following extract : 



" The memoir of M. Milne Edwards, read at the last meeting 

 of the Academy, on the 21st November, makes it necessary that 

 I should request the Academy to accept at my hand the five 

 first plates of a work which I have been preparing for a long 

 time upon the fossil polypidoms of the chalk formation ; so 

 that it may clearly appear, when my treatise is published, which 

 I expect will be in a few months, that my researches are not 

 posterior to those of Mr Edwards. 



" These plates represent twenty-two species of foraminated 

 polypidoms of the chalk of Touraine ; the three other plates, 

 which are nearly finished, will complete a series which com- 

 prehends the foraminated polypidoms of that locality, and of 

 many analogous cretaceous formations. 



" A simple inspection of these plates will prove that I have 

 no more neglected, than M. Edwards has done, the changes 

 which are produced by age in the Eschara, and that I have 

 moreover extended this observation to two other groups [of 

 the Millepora and Retepora. This has enabled me consider- 

 ably to reduce the number of species, and to explain the mode 

 in which the testaceous matter is deposited and increased in 

 thickness. In fact I have found in the living animals of many 

 of the neighbouring genera, numerous filiform tentacula which 



