PROCEEDINGS 



OF 



THE ROYAL IRISH ACADEMY. 



1812. No. 38. 



January 23. 



Rev. JAMES H. TODD, D.D., Vice-President, in tlie 

 Chair. 



Mr. G. J. Allman, read the following paper on the Mus- 

 cular System of certain fresh water ascidian Zoophytes, being 

 the first of a series of memoirs which he proposed present- 

 ing to the Academy on the physiological and zoological his- 

 tory of the zoophytes of fresh water. 



" The subject on which I have now the honour of ad- 

 dressing the Academy, belongs to a hitherto but little inves- 

 tigated department of zoology, the structure of the ascidian 

 zoophytes* of fresh water. Our present knowledge of these 

 minute creatures is chiefly due to Raspail, the distinguished 

 French naturalist and chemist, whose reseai'ches into the 

 structure of Alcyonella Stagnorum, are characterized by 

 much patient observation,f while in these countries the sub- 

 ject has been totally neglected. Not so, however, with the 

 ascidian zoophytes of the ocean; these interesting animals 

 have had both here and on the continent some able investi- 

 gators, among whom none deserve to be mentioned before 



* The zoophyta ascidioida of Johnston are synonymous with the bryozoa of 

 Ehrenberg, and the ciliobrachiata of Farre, and include all those zoophytes whose 

 organization is referrible to the niolluscan type. 



■f Compte rendu des seances de I'Academie des Sciences. 4 Fcvrier, 1839. 



VOL. II. 2 D 



