1893.J MICROSCOPICAL JOURNAL. 357 



Thirdly, tluit no deposit ot free material takes place, the for- 

 eign substance being contained exclusively in leucocytes, with 

 the one excejition of the splenic cells, where carbon is present. 

 This latter position is a secondary result. From the above it is 

 concluded that probably the fate of many leucocytes is to wan- 

 der out on mucous and e})idermic surfaces and to pass away 

 with waste products. Many must also meet their end in sple- 

 nic cells, as is shown by the considerable amount of carbon 

 present there. The fate of this carbon is left undetermined 

 from want of time to pursue the investigation further. 



To Color Oranges Red. — An ingenous rascal has found 

 out how to make *' blood " oranges. They sell better by color- 

 ing the rind; it is not necessar}^ to color the pulp. A micro- 

 scopical examination of some taken in the market showed in 

 a section of the epicarp the presence of a coloring matter with 

 a violet tinge localized in the glands and not passing beyond 

 the cuticle. At certain points, wliere it had accumulated near 

 the glands, the color w^as dark red. The coloring matter used 

 is said to be scarlet of Biebrich (Rocelline), which is a nitro de- 

 rivative of amidouzobenzol, obtained by adding diazobenzol to 

 an acid solution of b-nai)hthol. It is applied in aqueous solu- 

 tion and is not poisonous. 



Com})Osition of Mule's Milk. — Prof. A. B. Aubert reports 

 as follows: After being kept eight days no curdling took place, 

 but simply the separation of a very fine flocculent floating 

 coagulum. The fiit globules generally proved rather small; 

 approximately 10 per cent, averaging 0.001 mm., in diameter, 

 40 per cent, from 0.0018 to 0.0037 mm., 40 per cent, varied from 

 0.0037 to 0.0092 mm., the remainder running from 0.C092 to 

 0.0222 mm. and over. The quantity of albumen was found to 

 be very small, not over 0.5 per cent. The results of analysis 

 are published in the Journal of Chemistry for June, 1893. 



MICROSCOPICAL SOCIETIEis. 



Quekett Club, London. 

 October 20, 1893. — Swift & Son exhibited their new biological 

 microscopes with tripod stand of the Powell it Lealand pattern. 



