Analytical 



of aniline, both of its forms produce a lively evolution of 

 carbon dioxide (Wohl, 1907), even at temperatures as low as 

 10°. Both forms are insoluble in chloroform and benzene 

 (distinction from indole-acetic acid), but the higher-melting 

 form is said to be more soluble in ether than the other is. 



Vitamins 



Chemical methods for the estimation of vitamin C are 

 reviewed by Gstirner (1939), who considers the foremost 

 method to be the standard one of J. Tillmans [Chem. Ahs. 25, 

 5692; variously modified since). What appears to be a more 

 reliable method for determining ascorbic acid in urine has 

 been described by Roe and Hall (1939). 



For a biological method of determination of vitamin B^ in 

 urine by its effect on growth of the fungus Phycomyces, see 

 Villela (1938) ; for the original Phycomyces method, see 

 Schopfer and Jung (1938). For a fluorescence method of 

 estimation of vitamin Bi, see Marrack and Hollering (1939). 



Wenfs Pea Test 

 A simple test for the presence of at least some growth- 

 substances has been described by Went (1934). It was 

 devised to test for the presence and rough quantitative 

 estimation of auxin, but works equally well with indolyl-acetic 

 acid. 



Peas are germinated in any convenient manner (on damp 

 cloth, sand, or blotting paper) in a darkened cupboard or 

 room maintained at about 25° C. No nutrient solution is 

 required, and small amounts of light do not matter so long as 

 the shoots grow and remain straight. When the shoots are 

 from 5 to 20 cm. long they are ready for use. The variety of 

 peas mentioned by Went was Alaska. 



The description that follows is given in Went's words: 



"Pieces of stem 2 to 20 cm. long are cut about 5 mm. 

 below the terminal bud, and are used either directly or 

 4 to 8 hours after cutting. Immediately before application 

 of the auxin solutions, the top of the cut piece of stem is 

 split lengthwise by an exactly median cut with a razor 



129 



