470 CHAPTER XXXIV. 



1896, p. 227) fixes with sublimate or picro-acetic acid, and 

 stains sections with iron hasmatoxylin followed by saturated 

 aqueous solution of Orange G. 



846. Chsetopoda : Fixation. Lumbricus may be anaesthetised 

 by putting the animals into water with a few drops of chloro- 

 form. PERKIER prefers not to let the chloroform act directly 

 in solution on the animals, but to put them into water in a 

 shallow dish, set up a watch glass with chloroform in the 

 corner of it, and cover the whole. In half an hour the worms 

 will be more or less narcotised, and if allowed to remain will 

 die in a state of extension. 



CERFONTAINE (Arch, de BioL, x, 1890, p. 327; Zeit.f.u-iss. 

 MiJi., viii, 2, 1891, p. 210) much recommends curare, ad- 

 ministered by interstitial injection of a dose of about 2 c.c. 

 of a 1 : 500 solution. The animal should afterwards be put 

 into water, and after a quarter of an hour will be found 

 dead. 



In order to kill Criodrilns lacuum, COLLIN (Zeit. f. iviss. 

 ZooL, xlvi, 1888, p. 474) puts the animals into a closed vessel 

 with a little water, and hangs up in it a strip of blotting- 

 paper soaked in chloroform. KUKENTHAL (Die mik. Teclmik,. 

 1885 ; Zeit. f. iviss. Mik., 1886, p. 61) puts Annelids into a 

 glass cylinder filled with water to the height of 10 centimetres,, 

 and then pours 70 per cent, alcohol to a depth of one to two 

 centimetres on to the water. The animals will be found suffi- 

 ciently narcotised for fixation in from four to eight hours. 

 For Opheliadas he also employs O'l per cent, of chloral hydrate 

 in sea water. 



Many marine Chastopoda may be successfully narcotised 

 (S. Lo BIANCO) in sea water containing 5 per cent, of alcohol, 

 or by means of the mixture 16. 



The Polycliseta sedentaria offer the difficulty of a complex 

 and very contractile branchial apparatus. They may some- 

 times be satisfactorily fixed by bringing them rapidly into 

 corrosive sublimate. Cold, not hot solutions should be 

 taken, as heat frequently shrivels up the branchias. The 

 species of Polycliteta errantia that offer a contractile branchial 

 apparatus, as Eunice and Onuphis, may be treated in the 

 same way. 



S. Lo BIANCO advises killing Chietopteridas, Sternaspida},. 



