INVERTEBRATES 607 



in paraffin oven at 56° C. in butyl alcohol saturated with paraffin 

 for twenty-four hours, then pure ])arallin for twenty-four hours. 



Braun (see Journ. Hoy. Mic. Soc, 1885, p. 897) reconiniends that 

 small unstained Nematodes be mounted in a mixture of 20 parts 

 gelatin, 100 parts glycerin, 120 parts water, and 2 parts carbolic acid, 

 which is melted at the moment of using. Canada balsam, curiously 

 enough, is said to sometimes make Nematodes opaque. 



Demonstration of living Trichimv. Barnes (Amer. Mon. mik. Journ., 

 xiv, 1893, p. 104) digests trichinised muscle (of the size of a pea) in a 

 mixture of 3 gr. of pepsin, 2 dr. of water, and 2 minims of hydrochloric 

 acid, kept at body temperature for about three hours. The flesh and 

 cysts being dissolved, the fluid is poured into a conical glass, and 

 allowed to settle ; the trichinic are drawn off from the bottom with a 

 pipette, got on to a slide with water and examined on a hot stage. 



Graham (Arch. mik. Anat., 1, 1897, p. 216) isolates Trichinae by 

 macerating for one or two days in 2 per cent, acetic acid, staining with 

 aceto-carmine, and teasing. 



o' 



1207. Nemertina. Lee's best results have always been obtained 

 by fixing with cold saturated sublimate solution, acidified with 

 acetic acid. The other usual fixing agents, such as the osmic 

 and chromic mixtures, seem to act as irritants, and provoke such 

 violent muscular contractions that the whole of the tissues are 

 crushed out of shape by them. 



Professor du Plessis has suggested to Lee fixing with hot 

 (almost boiling) w^ater. Lee has tried it and found the animals 

 die in extension, without vomiting their proboscides. So also 

 JouBiN, Bull. Mus. Hist. Nat, 1905, p. 326. 



Lee has tried Foettinger's chloral hydrate method (§ 19). 

 His specimens died fairly extended, but vomited their probo- 

 scides. According to Lo Bianco narcotisation with a solution 

 of 0-1 to 0-2 per cent, in sea-water for six to twelve hours is 

 useful. 



Oestergren (§ 17) recommends his ether water. 

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

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

 chloroform. 



For staining fixed specimens in iota Lee found that it was 

 well-nigh necessary to employ alcoholic stains. Borax carmine or 

 Mayer's alcoholic carmine may be recommended ; not so cochineal 

 or hjematoxylin stains, on account of the energy with which they 

 are held by the mucin in the skin. 



Sections by the paraffin method, after })enetration with oil of 

 cedar (chloroform w^ill 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 intes- 

 tine by the intra-vitam methylen-blue method. lie injects the 

 animals with 0-5 per cent, solution in distilled water, or 0-5 per 



