592 INVERTEBRATES 



§ 17. For Opisthobranchiata Lee recommended sudden killing 

 with liquid of Perenyi, or the acetic method, § 89. Aplysia may 

 first be narcotised by subcutaneous injection of about 1 c.c. of a 

 5 to 10 per cent, solution of hydrochlorate of cocaine (Robert, 

 Bull. Sclent, de la France, etc., 1890, p. 449 ; Zeit. xciss. mile, ix, 

 1892, p. 216). For Lo Bianco's various methods see the original, 

 p. 467. 



For Pteropoda in general, liquid of Perenyi. Creseis is a 

 difficult form. Lo Bianco advises the alcohol method, § 17. 

 For the Gymnosomata he narcotises with 0-1 per cent, chloral 

 hydrate. 



For terrestrial Gastropods see §§ 23 and 25. Marchi {Arch, 

 mik. Anat., 1867, p. 204) gets rid of the mucus of the integu- 

 ment of Limax, which may be an obstacle to preparation, by 

 putting the living animal into moderately concentrated salt 

 solution, in which it throws off its mucus and dies in a few hours. 



Lang {Anat. Hefte, 1902, p. 84) puts Helix into water with 

 enough chromic acid to make it of a Rhine-wine colour, with an 

 air-tight cover to the vessel, and when the animals are extruded 

 injects into them a quarter to a half of a syringe of 1 per cent, 

 cocaine, and after five to fifteen minutes dissects and fixes. 



Heymans {Bull. Acad. Belg., xxxii, 1896, p. 578) injects ethyl 

 bromide under the skin of Cephalopoda. 



Lo Bianco uses for fixing them his chromo-acetic acid, No. 1 

 (§ 44), with a double quantity of acetic acid, for twenty-four 

 hours. 



1171. Liver of Mollusca. Enriques {Mitth. Zool. Stat. Neapel, 

 XV, 1901, p. 289) fixes the liver of Octopus and Sepia with subli- 

 mate. For Ajjlysia (especially in summer) alcohol, formol, 

 and chromic mixtures are counter-indicated, on account of the 

 carbohydrates in the cell. Sublimate is best. 



1172. Nervous System of Pulmonata. B. de Nabias {Act. Soc. 

 Linn. Bordeaux, 1894 ; Rech. Hist, centres nerveux des Gastero- 

 podes, 1894, p. 23) opens the animals and fixes the ganglia for 

 one hour in a mixture of 6 parts glacial acetic acid to 100 of 90 

 per cent, alcohol, or for fifteen to twenty minutes in 5 per cent, 

 sublimate with 5 per cent, acetic acid. He stains in bulk, with 

 Renaut's haematoxylic eosin, or R. Heidenhain's ha?matoxylin, 

 or a copper ha?matoxylin of Viallanes, and imbeds in paraffin. 

 He also stains by the rapid method of Golgi. imbedding, how- 

 ever, the ganglia in celloidin directly after the hardening in 

 osmic acid and bichromate, and treating the sections with the 

 silver (p. 500). He stains with mcthylcn blue by treating the 

 ganglia in situ for twelve to twenty-four hours with a 1 per cent, 

 solution. 



Dreyer {Zeit. xciss. Zool., xcvi, 1910, p. 380) narcotises Nudi- 

 branchs with cocaine, and for studying the nerves fixes them 



