610 INVERTEBRATES 



which in Acoela and Alloiocoela seem to be destroyed by swelling. 

 The same method is also good for the parenchyma of Aniphichcerus 

 cinereus, Convoluia jmradoxa and C. sordida. Sublimate is good 

 for Convoluta Roscoffensis. The nervous system may be investi- 

 gated by the methods of Delage. 



For Dendrocoela sublimate solutions, sometimes hot, appear 

 indicated for fixing ; see the mixture of Lang, § 69, also Chichkoff 

 {Arch, de Biol., xii, 1892, p. 438). 



Arnold [Arch. Zellforsch., iii, 1909, p. 433) kills Dendroccelum 

 in extension with strong liquid of Flemming. 



Oestergren narcotises Dendrocoelum with his ether-water, § 17. 

 Jaenichen {Zeit. zviss. Zool., Ixii, 1896, p. 256) advises for Planaria, 

 eyes especially, picro-sulphuric acid for an hour or two ; osmic 

 acid is not good, and liquid of Miiller macerates. He stains with 

 borax carmine, makes sections, and puts them for ten minutes 

 into osmic acid, then for five minutes into pyroligneous acid, on 

 the top of the stove. He macerates the visual rods in a mixture 

 of 1 part common salt, 1 of acetic acid, and 100 of water. He 

 bleaches the pigment of the eyes with peroxide of hydrogen. 



WiLHELMi {ibid., Ixxx, 1906, p. 548) throws Triclads into almost 

 boiling mixture of Zenker, and after ten to thirty minutes removes 

 to water for some hours,, and then passes into iodine alcohol. 



ECHINODERMATA 



1211. Holothurioidea. These are difficult to fix on account of 

 their contracting with such violence under the influence of irritat- 

 ing reagents as to expel their viscera through the oral or cloacal 

 aperture. 



Vogt and Yung {Anat. Conip. Prat., p. 641) say that Ciicmnaria 

 Planci {C. doUolum, Marenzeller) is free from this vice ; but they 

 recommend that it be killed with fresh water, or by slow intoxica- 

 tion, § 19. 



Synapta may be allowed to die in a mixture of equal parts of 

 sea-water and ether or chloroform (S. Lo Bianco). 



Oestergren (§ 17) puts Synapta into his ether water, but 

 Dendrochirota first into magnesium sulphate of 1 to 2 per cent., 

 for some hours. 



Gerould {Bull. Mus. Harvard Coll., xxix, 1896, p. 125) para- 

 lyses Caiidina with sulphate of magnesia, § 23, and fixes with 

 liquid of Perenvi (or sublimate for the ovaries). 



Holothurids, Dr. Weber informs us, are admirably preserved 

 in formaldehyde ; a weak solution is sufficient. 



For the staining of muscles with methylen blue, see Iwanzoff, 

 Arch. mik. Anat., xlix, 1897, p. 103, and for the study of calcareous 

 plates, see Woodland, Quart. Journ. Micr. Sci., xlix, 1906, p. 534 

 (fixation with osmic acid, staining with picro-carniine, followed by 

 Lichtgriin). 



