ANTHOZOA. 371 



fectly satisfactory for the study of tlie chief phases of meta- 

 morphosis. 



Auricularia and Bipinnaria. The method described above 

 is equally applicable to these forms, and seems to be altogether 

 the best method for the study of the metamorphosis of Bipin- 

 iiaria. The earlier stages of the metamorphosis of Auricularia 

 are better studied by fixing with osmic acid, staining with 

 Beale's carmine, and mounting in glycerin. 



Larvse of Comatula. The best method for the study of the 

 embryonal development of Comatula consists in fixing with 

 liquid of Lang, and staining with dilute borax carmine. It 

 is important (for preparations that are not destined to be 

 sectioned) to use only dilute borax carmine, as the strong 

 solution produces an over-stain that cannot easily be reduced. 



Narcotisation by chloral hydrate before fixing is useful, 

 especially for the study of Pentacrinus larvae and of the young 

 Synaptsp formed from Auricularia. Without this precaution, 

 you generally get preparations of larvas either shut up (Penta- 

 crinus), or entirely deformed by contraction (young Synaptse). 



Coelenterata. 



741. Anthozoa: Fixation. HERTWIG'S method for killing 

 Actiniaria has been given, 9. The methods employed by 

 ANDRES have been given in great part in 10 and 13. In Le 

 Attinie, Fauna u. Flora d. Golfes v. Neapel, the following are 

 also given : Hot corrosive sublimate often gives good results. 

 In the case of the larger forms, the solution should be injected 

 into the gastric cavity, and a further quantity of the liquid be 

 poured over the animals. 



Freezing sometimes gives good results. A vessel containing 

 Actiniae is put into a recipient containing an ice-and-salt 

 freezing mixture and surrounded by cotton wool. After 

 freezing, the block of ice containing the animals is thawed in 

 alcohol or some other fixing liquid. 



The Zoantharia with calcareous skeletons are also difficult 

 to deal with 011 account of the great contractility of the 

 polyps. Sublimate solution, which ought very often to be 

 taken boiling, sometimes gives good results. DE CASTELLARNAU 

 (La Est. Zool. cle Napoles, p. 132) says that this process 



