324 THE FORAMINIFERA 



we are enabled to see whether the specimen is worth 

 the trouble of disintegration. 



To prepare the Barcode Bodies of Foraminifera. — 

 In order to examine the sarcode for structures such 

 as the nucleus, the gemmules or zoospores, and so 

 forth, it is essential to remove or decalcify the shell. 

 In order to do this successfully the body of the fora- 

 minifer, which is jellylike in consistence, must be 

 hardened ; and this process should go on side by side 

 with the dissolution of the shell. The best reagent for 

 doing this is undoubtedly that known as Perenyi's 

 Fluid. It consists of nitric acid, 10 per cent, sol., 

 4 vols. ; alcohol (absolute), 3 vols. ; chromic acid, 5 per 

 cent., 3 vols. 



If we are able to obtain the living animals by 

 dredging, the material should be bottled, until re- 

 quired, in weak spirit, or, what is perhaps better, a 

 weak solution of formalin. On selecting our specimens 

 for decalcification they may be placed on a thin 

 cover glass in the solution mentioned above, con- 

 tained preferably in a glass box with a lid, a covered 

 watch-glass, or other convenient vessel, and left 

 undisturbed until the solution of the shell is effected. 

 Should the organism require to be stained, the cover 

 glass with the specimen may be gently lifted by means 

 of a section-lifter, and transferred to a fresh vessel 

 containing water ; and afterwards to a weak solution 

 of picro-carmine. After the lapse of half an hour it 

 may be transferred to methylated spirit. If the speci- 

 men be washed in water after staining, the picric acid 

 is removed, otherwise it acts as a yellow stain to the 



