CHAPTER XXV. 281 



Anat. .Phys., Anat. Abth., 1897, p. 3). See also BRAUS, Morph. 

 Jahrb., xxxv, 1906, p. 250. 



613. Amphioxus. SOBOTTA (Arch. mik. Anat., 1, 1897, p. 20) 

 fixes for twenty-four hours in liquid of Flemming ; HATSCHEK (Arb. 

 Zool. Inst. Wien., iv, 1881) in picro-sulphuric acid. Impregnation 

 takes place in the evening, and segmentation is completed during 

 the night. 



LEGROS (Grundzuge, LEE and MAYER, 1910, p. 288) fixes ova 

 and embryos in equal parts of formol and Flemming. Sublimate 

 is not good ; Rabl's mixtures are better. Larvae and young animals 

 ought first to be anaesthetised with cocain in sea-water. After 

 fixation they should remain only for as short a time as possible in 

 alcohol. 



CERFONTAINE (Arch. Biol, xxii, 1906, p. 287) fixes with Flemming 

 or Hermann. For study of ova in toto he orients them on a slide in 

 clove-oil-collodion which he sets with chloroform, and adds balsam. 

 For sectioning, he orients in the same way on a layer of paraffin 

 spread on a cover glass and imbeds the whole in paraffin. 



614. Pelagic Fish Ova. WHITMAN (Amvr. Natural., xvii, 1883, pp. 

 1204-5 ; and Methods of Research, etc., p. 152). Fix by treatment first 

 for five to ten minutes with a mixture of equal parts of sea-water and 

 -J- per cent, osmic acid solution, and then for one or two days with a 

 solution (due to Eisig) of equal parts of 0-2 per cent, platinum chloride 

 and 1 per cent, chromic acid. Prick the membrane before transferring 

 to alcohol. See also AGASSIZ and WHITMAN, in Proc. Amer. Acad. Arts 

 and Sciences, xx, 1884 ; and COLLINGE, Ann. and Mag. Nat. Hist., x, 

 1892, p. 228. 



EAFFAELE (Mitth. Zool. Stat. Neapel, xii, 1895, p. 169) fixes chiefly 

 with liquid of Hermann (1 to 2 days), or with a mixture of Mingazzini 

 ( absolute alcohol 1, acetic acid 1, saturated sublimate solution in water 2). 



HEINKE and EHRENBAUM (<Wiss. Meeresunt. Komm. Wiss. Unt. D. 

 Meere, iii, Heligoland, 1900, pp. 205 and 213) prefer formol with 39 

 volumes of sea-water. 



Tunicata. 



615. Ova. DAVIDOPF (Mitth. Zool. Stat. Neapel, ix, 1, 1889, 

 p. 118) fixes the ova of Distaplia with a mixture of 3 parts of 

 saturated solution of corrosive sublimate and 1 of glacial acetic acid 

 for from half an hour to an hour ; or with a mixture of 3 parts of 

 saturated solution of picric acid and 1 of glacial acetic acid for 

 three to four hours ; then 70 per cent, alcohol. 



CASTLE (Bull. Mus. Harvard Coll., xxvii, 1896, p. 213) advises for 

 ova of Ciona liquid of Perenyi for twenty minutes, followed by 



