NUTRIENT MEDIA 61 



short time ; the eggs are now thoroughly rinsed in water 

 that has been well boiled. The eggs are finally rinsed in 

 strong alcohol and ether before they are inoculated. The 

 inoculation is performed as follows: The end is pierced 

 with a sterile needle, and the material to be inoculated is 

 introduced into the egg by means of a glass capillary tube, 

 from which it is blown with great care. The hole is now 

 closed with sterile cotton-wool. This method of cultiva- 

 tion is particularly well adapted for the cultivation of the 

 anaerobic bacteria. 



(20) Bread. — Bread and pastes formed by boiling up 

 wheaten flour or ground rice with water are employed 

 particularly for the growth of moulds. Slices of bread or 

 layers of the paste are placed in Petri dishes and steamed, 

 as in the case of other media. 



(21) Malt Extract. — Solutions of malt extract and in- 

 fusions of raisins and other fruits are extensively employed 

 in the study of the yeasts. The foregoing materials 

 thickened with gelatine or agar are useful foj: the growth 

 of those organisms which, like the yeasts and moulds, are 

 favoured by an acid medium. 



(22) Irish Moss Jelly. — This medium was devised by 

 Miquel for the study of the 'thermophilic' organisms, 

 which do not grow at a lower temperature than 50° C. 

 This medium, generally known as Miquel's high temperature 

 jelly, is prepared as follows : 400 grammes of Irish moss 

 (Carragheen, Fuscus crispus) are placed ia 10 litres of 

 boiling water and boiled for several hours ; the liquid is 

 then passed through a sieve, the filtrate boiled again, 

 and strained through fine linen. The filtrate is slowly 

 evaporated on a water-bath, and the residue dried at about 

 45° C. On adding 1 to 2 per cent, of the gelatinous 

 substance so obtained to ordinary nutrient broth, a culture 

 medium is obtained which remains solid at 50° C. 



