228 SEA -SIDE STUDIES. 



It is worth noting that M. Hollard equally failed in 

 detecting an acid or alkaline reaction/"" which is a con- 

 firmation of my experiments. 



The Actinise do not effect their preparation of nutri- 

 ment by chemical means ; and in our strict sense of 

 the term, they cannot be said to digest. I was anxious 

 to see how far mechanical means were employed, and 

 for this Reaumur's admirable experiment was a guide. 

 In his day it was supposed that digestion was a purely 

 mechanical oj)eration, the food being ground into a 

 pulp in the stomach. He took hollow silver balls, 

 perforated with holes, and filling them with meat, 

 caused them to be swallowed by a dog. When they 

 had remained a suitable period in the animal's stomach, 

 they were withdrawn by the thread attached to them. 

 If the digestive process were mechanical, the meat 

 would be protected from all grinding action, by the 

 silver covering ; if chemical, the meat would be di- 

 gested ; and digested (or rather chymified) it proved 

 to be ; showing that a solvent fluid had penetrated the 

 holes, and dissolved the meat. I took two pieces of 

 quill, of about half an inch in length, open at both 

 ends, and having six good openings cut in the sides, 

 thus afi"ording ample means for any solvent fluid to 

 exert its action on the roast-beef enclosed in the quill. 

 On examination of the ejected quills, I found no ap- 



■*• " II est remarquable, et je m'en suis souvent assure, que les 

 papiers reactifs plonges dans cet organe, et dans la cavite inferieure, 

 soit au moment de la digestion, soit chez I'animal k jeftn, ne donnent 

 aucun indice d'acidite, ni d'alcalinite." — ''Etudes Zoologiques sur le 

 genre Actinia." — Revue et Magazin de Zoologie, No. 4. ISo-J. 



