456 SUMMARY OF CURRENT RESEARCHES RELATING TO 



P. Technique,* 

 CD Collecting: Objects, including- Culture Processes. 

 Collecting Salt-water Sponges.! -The collector, says Mr. W. B Hardv 

 should be on the ground an hour before the tide begins to rise and 

 choose some sheltered nook among the rocks if the coast be a rocky 

 one, or about the piles of a pier if it be an open one. There will be 

 found attached to the under surface of inclined stones, and in the clefts 

 of the rocks, on sea-weed, and in any sheltered spots where there is- 

 good surface for attachment, and where the sun does not strike too 

 strongly, tenacious masses of sponge, yellow, green, brown, or orange- 

 colour, and with large orifices on the surface. The most common is 

 of a sponge-yellow colour, shading into green on exposed parts. This 

 is the Hahchondna pamcea, or " bread-crumb " sponge of Ellis Another 

 common form, of a salmon colour, is Eymeniacidon sanguinea. Pieces 

 of the sponge should be removed as carefully as possible and taken 

 home m a considerable quantity of fresh water. 



Nutritive Media for the Cultivation of Bacteria.l-M. L. Benoist 

 gives the following methods for preparing media for the cultivation 

 01 micro-organisms : — 



(1) Meat broth :-~In 4 litres of water are boiled 1 or 2 kg 

 of lean beef. It is kept boiling 5 hours, and during this time con- 

 tinually skimmed When cold on the next day the fat is carefully re- 

 moved and the liquid then filtered. It is then brought up to its 

 S'cTiftr' n*^ -^^*^^l--d with a 1:10 solution of caus^tic soda 

 (dcm. o± this solution always suffice to neutralize the acids in 1 k- 



li^^i}' A^^^^""^?^'^^^ *^" ^"^^ ^« b°^l^^ ^g^i^ for ten minutes 

 and afterwards filtered To every 1000 cm. of the filtrate 10 g. of 

 sodium chloride are added. *= 



n.f 1^^ 7^^ foregoing may be satisfactorily replaced by the following 

 artificial bouillon :-Water, 1000; pepton Chapoteau, 20; gelatin 2 



ITati 'If' f'^^ '• «^l?^i^%^f --^--^ 5. With the exc^pifon o?'the 

 gelatin the foregoing ingredients are boiled for a few minutes and 



TddTd^o' ^"^'T \^^i^-l-d «- --ture is filtered, and to it are 

 added 20 cm of a 10 per cent, gelatin previously clarified. The fluid 

 thus obtained IS always perfectly limpid and its composition invariable 

 r.. P>*^^^*^^^,i^^ gelatin :-Water, 1000; gelatin Coiguet No. 1 100- 

 pep^n Chapoteau, 20; chloride of sodium 5 



with h-/'n''^'-r^''*"^ ^' dissolving the' gelatin in should be lined 

 with tin or silver, and not with porcelain. The pepton and salt 



from ^the"f(;-/'T':i!^ '"i *'' ^^^^^ ^^^*^^' *^^ ^^^^^ - withdrawn 

 nZ^ if I "" w*^ ,^'^^V^ *^"^ ^^^^^ ^^ pieces a^d kept stirred up 

 means of a ''"^^^''fy.^^^'f-^^- . The mixture is then neStrali.ed by 

 rSs for 1 no '!'"'' of caustic soda (1 ccm. of the alkaline solution 

 separatelv^-n ?0n^' ^f '*?^- ^^" ^^^*^^ ^^ ^'^'^ eggs, dissolved 



of^ the fl^:id i. K'Tv'rfo^n^"'' ^ *^^^^ ""^^'^ ^^^^ the temperature 

 o± the fluid IS about 60° C. ; the mixture is then vigorously shaken 



cessesT n SS^ObTcS'nl',^ g-"''^*''^f P'^^'"''' '"^''^^'^^ Culture Pro- 



(4)Staiin/S infecS r^^M *^"?^^g'. i°°l"ding Imbedding and Microtomes; 



(6) Miscellaneous ^^' ^^ ^^-^^^i^g' including slides, preservative fluids, &c. 



t Ann. de Mic'rographie. i. (1888) pp. 75-8. ^ Sci.-Gossip, 1889, p. 11. 



