604 INVERTEBRATES 



acid (§ 25), and fixing with liquid of P'lemming. He has also found 

 that lemon juice kills them in a state of very fair extension. 



Apathy succeeds with alcohol of 40 per cent. 



Graf {Jen. Zeit., 1893, p. 165) has obtained good results by 

 narcotising with a decoction of tobacco. 



1200. Injection. Whitman {Amer. Natural, 1886, p. 318) 

 states that very perfect natural injections may often be obtained 

 from leeches that have been hardened in weak chromic acid or 

 other chromic liquid. 



Jacquet {Mitth. Zool. Stat. Neapel, 1885, p. 298), for artificial 

 injections, puts leeches into water with a very small quantity of 

 chloroform, and allows them to remain a day or two in the water 

 before injecting them. 



1201. Nervous System, Impregnation with gold. Bristol 

 {Journ. of Morph., xv, 1898, p. 17) kills in formic acid of 15 to 

 20 per cent., puts for twenty-five minutes into 1 per cent, gold 

 chloride, reduces in formic acid of 1 per cent, (twelve to eighteen 

 hours), and imbeds in paraffin. See also §§ 376 et seq. 



1202. Nephridia. Shearer {Quart. Journ. Micr. Sci., Iv, 

 1910, p. 288) stains Histriohdella intra-vitam with a very weak 

 solution of methyl blue, which allows the course of the nephridia 

 to be made out. 



1203. Gephyrea. Vogt and Yung {Anat. Comp. Prat., p. 373) 

 direct that Siphunculus nudus be kept for some days in perfectly 

 clean basins of sea-water, changed every day, in order that the 

 intestines of the animals may be got free from sand, and then 

 anaesthetised with chloroform. 



Ward {Bull. Mus. Comp. Zool., Cambridge, Harvard Coll., 

 xxi, p. 144) puts them into a shallow dish with sea-water and 

 pours 5 per cent, alcohol in a thin film on to the surface of the 

 water, and as soon as they make no contractions on being stimu- 

 lated removes to 50 per cent, alcohol. 



Lo Bianco says killing with 0-5 per cent, chromic acid or 

 with 0-1 per cent, chloral hydrate in sea-water may be tried. 

 Phascolosoma and Phoronis should be treated by the alcohol 

 method, larva," of Si])unculus with cocaine, § 20. 



Apel {Zeit wiss. Zool., xlii, 1885, p. 461) puts Priapulus and 

 Hulicryptus into a vessel with sea-water and heats on a water 

 bath to 40° C. ; or they may be thrown into boiling water, which 

 paralyses them so that they can be quickly cut open and thrown 

 into ^ per cent, chromic acid or picro-sulphuric acid. 



1204. Rotatoria. For quieting them for study in the living 

 state, Weber {Arch, de Biol., viii, 4, 1888, p. 713) finds that 2 per 

 cent, solution of hydrochlorate of cocaine gives the best results. 

 Warm water gave him good results for large species, such as those 

 of Hydatina and Brachionus. 



Hardy {Journ. Roy. Mic. Soc, 1889, p. 475) recommends 



