CHAPTER XXXVI. 515 



Prof. DU PLESSIS has suggested to me fixing with hot (almost 

 boiling) water. I have tried it and found the animals die in extension, 

 without vomiting their proboscides. So also JOUBIN, Bull. Mus. 

 Hist. Nat., 1905, p. 326. 



I have tried FOETTINGER'S chloral hydrate method ( 20). My 

 specimens died fairly extended, but vomited their proboscides. 

 According to Lo BIANCO narcotisation with a solution of 0-1 to 

 -2 per cent, in sea water for six to twelve hours is useful. 



OESTERGREN ( 18) recommends his ether water. 



DENDY (see Journ. Roy. Mic. Soc., 1893, p. 116) has succeeded 

 with Geonemertes by exposing it for half a minute to the vapour of 

 chloroform. 



For staining fixed specimens in toto I have found that it is well-nigh 

 necessary to employ alcoholic stains. Borax-carmine or Mayer's 

 alcoholic carmine may be recommended ; not so cochineal or 

 haematoxylin stains, on account of the energy with which they are 

 held by the mucin in the skin. 



Sections by the paraffin method, after penetration with oil of 

 cedar (chloroform will fail to penetrate sometimes after a lapse of 

 weeks). 



BURGER (Fauna u. Flora Golf. Neapel, xxii, 1895, p. 443) studies 

 the nervous system, nephridia, skin, muscle and intestine by the 

 intra vitam methylen-blue method. He injects the animals with 

 -5 per cent, solution in distilled water, or -5 per cent, salt water, 

 and allows them to lie for six -to twelve hours or more in moist 

 blotting-paper. 



See also MONTGOMERY (ZooL Jahrb., Abth. Morph., x, 1897, p. 6) ; and 

 BOHMIG (Zeit. wiss. Zool., Ixiv, 1898, p. 484). 



967. Cestodes. Wash gently in 1 per cent, saline, and then fix 

 in hot corrosive sublimate acetic (at circa 50 C.) and allow the tape- 

 worms to remain in the dish till the fluid becomes cold. Wash in 

 running water for twelve hours and transfer to 70 per cent, alcohol. 

 Stain as in general methods. 



As pointed out by VOGT and YUNG (Traite d'Anat. Comp. Prat., 

 p. 204), the observation of the living animal may be of service, 

 especially in the study of the excretory system. And, as shown by 

 PINTNER, Tsenise may be preserved alive for several days in common 

 water to which a little white of egg has been added. 



TOWER (ZooL Jahrb., xiii, 1899, p. 363) has kept Moniezia expansa 

 alive for several days in a mixture of 100 c.c. of tap water, 10 grs. of 

 white of egg, 2 of pepsin, 2 of sugar, and 5 of prepared beef 



(" Bovox "). Chloride of sodium, he says, should be avoided. 



332 



