ZOOLOGY AND BOTAHY, MICROSCOPY, ETC. 897 



prevents the development of the Schizomycetes, but not of the moulds. 

 A solution stronger than 2 per cent, acts unfavourably on many 

 tissues. 



Mounting Media for Nematodes.* — The following is recom- 

 mended by Dr. M. Braun as a medium in which unstained prepara- 

 tions of small nematodes may be mounted: — Gelatin 20, glycerin 

 100, water 120, carbolic acid 2. The preparations are treated 

 beneath the cover-glass (after previous treatment with Miiller's fluid 

 and distilled water) with weak alcohol (first 25 per cent, and then 

 40 per cent.). This is removed by placing at the edge of the cover- 

 glass glycerin diluted with an equal part of water ; by the evapora- 

 tion of the water pure glycerin remains. The cover-glass is then 

 lifted up, and the gelatin, rendered fluid by warming, applied. A 

 sealing varnish is not necessary. 



Preparing Myzostoma.t — As preserved specimens did not give 

 favourable results, their development was chiefly studied by Mr. J. 

 Beard on the living animal. If plenty of naturally impregnated 

 Comatula with adult Myzostoma gldbrum can be obtained, the arms are 

 cut off by the calyx and placed in a vessel filled with sea water. On 

 the following day the Comatula are removed, and at the bottom of the 

 glass the ova or larva of Myzostoma will be found. They can be 

 kept alive from 4-5 days. But as only a few ova can be obtained, 

 and the Comatula die in a few days, ova artificially impregnated are 

 used. A number of adult Myzostoma are removed from their host 

 and placed in a watch-glass containing 2-3 teaspoonfuls of freshly 

 filtered sea water. They are then torn with needles and left for two 

 or three hours. The pieces of Myzostoma are then fished out ; the 

 ova which remain at the bottom of the vessel are supplied with fresh 

 sea water every other day and also with air by means of Andres' 

 apparatus. Most larvae die in about six days. For the later stages 

 of development the Comatula are placed in a vessel containing a 

 mixture of sea water with 10 per cent, of alcohol. By this they are 

 slowly killed. On shaking the vessel Myzostoma glahrum and cirri- 

 ferum fall to the bottom. Alcohol is then gradually added until it 

 reaches 90 per cent. In this they are preserved. 



Sensitive Tests for Wood-fibre and Cellulose.1: — Dr. A. Ihl finds 

 that besides the well-known reagent phloroglucin, other i)henols stain 

 lignin in a characteristic way. An alcoholic solution of orcin acidulated 

 with hydrochloric acid stains woody fibre a beautiful dark red. Cellu- 

 lose remains unchanged . Eesorcin with alcohol and hydrochloric acid 

 gives a blue violet stain. Kesorcin with alcohol and sulphuric acid 

 (1 part CJIgO to 1/3 part HuSO,) gives a dark blue violet stain. To 

 cellulose a reddish hue. a-naphthol, alcohol, and hydrochloric acid 

 profluce a greenish hue: a-naphthol, alcohol (1 part), sulphuric acid 

 (1 part), impart a dark-green colour to wood, to cellulose a red-violet 



♦ Braur), M., ' Die thierisclien ParaHitcn des Mcnsclicn nobst cincr Anlci- 

 tung zur piuktiwchen licKchiiftigung mit der IJolmintliologio, fur iStudirende uud 

 AerzU;.' 



t ZcitBchr. f. Wiss. Mikr., ii. (1885) p. 231. 



X Cliom. Ztg., 188.'>, p. 2GG. 



