THE MICROTOMIST' S VADE-MECUM

sometimes well to wash out with water for half an hour          Ibvfo
before passing into alcohol.                                    fOretP
30. Corrosive Sublimate (Lang's method'), first formula.     ga
For Planaria.-Take-                                             O I beliec
Distilled water    .    . 100 parts by weight.           gsult,
Chloride of sodium      .    6 to 10 parts.               O110ct;
Acetic acid  .     .    .    5 to  8  ,,                 asthiybaT
Bichloride of mercury   .    3 to 12  , Itest
(Alum   .    .    .     .    i).
The Planaria are to be placed on their backs and the mixture  hVrd
is to be poured over them. They die extended. After the         Oxe 011I
lapse of half an hour they are brought into alcohol, first of   h
70 per cent., then of 90 per cent., then absolute, and in two
days' time are sufficiently hardened.                           be show
Second formula.2-Make a concentrated solution of corrosive    hiittle
sublimate in picro-sulphuric acid, to which has been added 5    p
per cent. of acetic acid.                                       cut
Third formula.'-Take a concentrated aqueous solution of
corrosive sublimate.                                            tk
31. Corrosive Sublimate Solutions.4-Any of these solutions
may sometimes be used hot, with good results. They are
suitable for Hydroida, Corallida, small Ctenophora, some
Gephyrea, Balanoglossus, Echinodermata, Sagitta, many An-
nelida, Rhabdoccela, and especially for Dendroccela, for which  sol
last they are the only methods that give good histological
results. Cestoda and Trematoda, and larvae of Turbellaria
may be added to the list. Lately good results have been
obtained with   crustacea with   thin integuments, such as
Sapphirina, and other Copepods, and with larvae of Decapods.     ren
Good results have not been obtained with Arthropoda in           aiReti
general.                                                         lelate
'Zool. Anzeiger,' 1878, i, p.14.
Ibid., 1879, ii, p. 46.
3 Loc. cit
' Mitth. Zool. Stat. Neapel,' ii, 1881, p. 11.

32


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