SOME METHODS FOR LOWER ANIMALS. 485 



succeeds well with Dendrophyllia, Antipathes, Astroides, 

 Cladocora, and Caryophyllia. 



See also Lo BIANCO, loc. cit., p. 446. 



Sections. Besides the usual methods for sectioning decal- 

 cified specimens, we have the methods of von Koch and 

 Ehrenbaum, 172 and 173, for undecalcified specimens. 



869. The Alcyonaria have also extremely contractile polyps. 

 In a former edition I suggested for their fixation either hot 

 sublimate solution or glacial acetic acid ( 82). S. Lo BIANCO 

 has since recommended essentially similar processes. GTAEBINI 

 (Manuals, p. 151) says that the polyps may be fixed in the 

 state of extension by drenching them with ether, and then 

 bringing them into strong alcohol. 



WILSON (Mittli. Zool Stat. Neapel, 1884, p. 3) kills Alcyo- 

 naria with a mixture of one part of strong acetic acid and 

 two parts of concentrated solution of corrosive sublimate, the 

 animals being removed as soon as dead and hardened for two 

 or three hours in concentrated sublimate solution. 



870. Zoantharia and Alcyonaria. BRADN (Zool. Anz., 1886, 

 p. 458) proceeds as follows for Alcyoninm palmatum, Sym- 

 podium coralloides, Gorgonia verrucosa, Caryopliyllia cyaihus, 

 and Palytlioa axinellse : The animals are left for a day or 

 two in a glass vessel, so that the polyps may become 

 thoroughly extended. They are then suddenly drenched 

 with a mixture of 20 to 25 c.c. of concentrated solution of 

 sublimate in sea water with four to five drops of 1 per cent, 

 osmic acid. This is allowed to act for five minutes, and is 

 followed by successive alcohols. 



(This method also gives good results with Hydra and some 

 Bryozoa and Rotifers.) 

 See also 12. 



871. Hydroidea, Polypoid Forms. For suitable narcotisation 

 methods see 13 et seq. 



For killing by heat see 11. 



Fixation. In general the polyps may be very well killed 

 in saturated sublimate solution, in which they should be 

 plunged for an instant merely, and be brought into alcohol. 

 The solution should be employed cold in genei'al for Gymno- 

 blastea, hot for most Calyptoblastea. 



