476 CIIAFl'Ell XXXVJ. 



917. Immobilisation. — See the narcotisation methods §§ 20 

 to 25. 



According to Schdemaybr [Jen. Zeit., xxiv, 1890, p. 402), 

 nitrate of strychnin, of 0-01 per cent, or less, gives good 

 results with some forms, amongst which are Stenlor and 

 Garchesiiim. Antipyrin (O^l per cent.), or cocaine of O'Ol 

 per cent., seems only to have given good results as i-egards 

 the extension of the stalk in stalked forms. 



EisMOND [Zool. Anz., xiii, 1890, p. 723) slows the movements 

 of small organisms (small worms and Crustacea as well as 

 Ciliata) by means of a drop of thick aqueous solution of 

 cherry-tree gum added to the water containing them (gum 

 arabic and the like, it is stated, will not do). The objects 

 remain fixed in their places, with cilia actively moving, and 

 all vital processes retaining their full activity. 



Certes (Bull. Soc. Zool. France, xvi, 1891, p. 93) has 

 found that an intra vitam stain may be obtained by adding 

 methyl blue or " violet dahlia, No. 170" to the gum solution. 



Jensen (after Stahl ; see Biol. Gentralhl., xii, 1892, p. 

 558) makes a solution of 3 grammes of gelatin in 100 c.c. 

 of ordinary water by the aid of heat. This makes a jelly at 

 the normal temperature. It is slightly warmed, and a drop 

 of it is mixed in a watch glass with a drop of water con- 

 taining the organisms. 



See alsoVoLK, aide, § 886; Statkewitsch,^'1cc/(. Protistenk., 

 V, 1904, p. 17; Lyon, Amer. Journ. Phys , xiv, 1905, p. 427 

 (neutralised gum) . 



918. Staining intra vitavi. — See hereon Brandt {Verh. 

 pliysiol. Gcs. Berlin, 1878) ; Certes [Bull. Sue. Zool., 25 

 janv., 1881) ; and Henneguy {Soc. Philom., 12 fev., 1881). 

 See also § 208. 



Braisidt recommends a 1 : 3000 solution of Bismarck brown; 

 also (Biol. Geiitralb., i, 1881, p. 202) "a dilute solution of 

 hematoxylin." 



Certes {op. cit., pp. 21, 226, 264, and Zool. Ann., iv, 1881, 

 pp. 208, 287) found that living Infusoria stain in weak solu- 

 tions of cyanin, Bismarck brown, dahlia, violet 5 B, chrysoidin, 

 nigrosin, methylen blue, malacliite green, iodine green, and 

 other tar colours, and hasmatoxylin. The solutions should be 

 made with the liquid that constitutes the natural habitat of 



