EMBBYOLOGICAL METHODS. 313 



Hamburger [Zeit. wiss. Zool., xcvi^ 1910, p. 3) fixes ova of 

 Argyroneta in Gilson's mixture. 



634, Limulus. — Kingsley [Jourii. MurpJi., vii, 1892, p. 38) 

 kills ova by heating in sea-water to 70° or 75° C. and brings 

 into alcohol of 30 to 70 per cent. Similarly Kishinouye, 

 Journ. Coll. Sci. Japan, v, 1893, p. 56. 



635. Deeapoda. — Reichenbach (4?)/i. Senchenherg Ges. Frank- 

 furt, xiv, 1886, p. 2) fixes ova of Astacus in water gradually 

 warmed to 60° or 70° 0. (if the chorion should burst, that 

 is no evil), hardens for twenty-four hours in 1 to 2 per cent, 

 bichromate of potash or 0'5 per cent, chromic acid, washes 

 out for the same time in running water, and brings into 

 alcohol. Remove the chorion, and remove the embryo from 

 the yolk with a sharp knife. 



Hereick [Ikdl. IT. S. Fish. Cumvi., xv, 1896, p. 226) 

 kills the ova in hot water, shells and fixes in picro-sulphuric 

 acid. 



For Homarus, see Waite, Bull. Mus. Comp. Zool., xxxv, 

 1899, p. 155. 



636, AmpMpoda. — Della "Valt.k; {Fauna u. Flora Golf. 

 Neapel, xx, Monog., 1893, p. 170) puts ova of Orchestia by 

 means of a pipette into boiling, cold-saturated sublimate 

 solution, removes them instantly into sea-water, and thence 

 into weak alcohol. If the chorion does not burst of itself it 

 must be pricked with a needle. 



637, Cladocera. — Haekee {Zelhn. u. Befruchtungslehre, 1899, 

 p. 60) fixes females of Sida with winter eggs in a hot mix- 

 ture of 100 c.c. alcohol of 70 per cent, with 1 to 2 c.c. satu- 

 rated sol. of sublimate. See also Samtee, Zeit. iviss. Zool, 

 Ixviii, 1900, p. 176. 



638, Copepoda.— Keukgee [Arch. Zellforsch., vi, 1911, p. 

 173) fixes ovaries of Harpactida in Zenker's mixture with 

 10 per cent, of formol added. No other liquids give good 

 results. 



