248 HUMUS — HUMOGEN. 



and phosphoric acid ])roportionately greater than its power to 

 bring nitrogen to the plant ? This wotdd at least afford a par- 

 tial explanation of its properties. Moreover, this explanation 

 is supported, in a way, by the announcement that Bottomley has 

 patented the action of certain bacteria which, given suit able 

 food and added to insoluble phosphates, will render them solul)le. 



Bottomley, however, seems to ascribe the exceptional proper- 

 ties of humogen principally to its content of plant vitamines 

 [" auximones " or accessory substances, as he calls them], sub- 

 stances which stand to the plant in a similar relationship that 

 Funk's and Hopkins' vitamines do to animals. 



There is really nothing wonderful in this, for e^■er\• year 

 some progress seems to have been made which has brought t!ie 

 life processes of plant and animal into closer relationshi]). 



Bottomley's claims in respect of the " auxiniones " in humo- 

 gen are supported by the following facts : 



1. The amounts of auximones present are of tlie same order of mag- 



nitude as the amounts of vitamines in foodstuffs. 



2. A very concentrated, if not pure, extract of auximones can be 



prepared from humogen by using precisely the same methods as 

 were used in isolating the vitamines of beri-beri and scurvey. 

 ,3. The extract thus prepared has just as potent an influence on iilant 

 growth as Hopkins's vitamines have on animal growtli. For 

 instance, 200 c.c of a water solution containing 0.35 gram per 

 million grams of water of what is known as the silver nitrate 

 fraction in the isolation of vitamines, z/s:., 0.00015 gram of 

 silver nitrate extract, is able to nourish, in conjunction with Det- 

 mer's solution, germinated wheat emliryos that have been deprived 

 of all trace of endosperm. 



These points, placed alongside the fact that scurvy vita- 

 mine is produced during the germination of seeds, would seem to 

 suggest a remarkable connection between auximones and 

 vitamines. 



In recognising that there are considerable differences be- 

 tween the two classes of 1)odies, it should also be remembered 

 that vitamines differ much among tliemselves. For instance, the 

 scurvy vitamine differs mtich from Hopkins' vitamine in that 

 the latter is fairly resistant to boiling temperatures, while suc'.i 

 a temperature absolutely destroys the former. IJottomlex's auxi- 

 mones, although much resembling the scurvy vitamine, are un- 

 like it in that tiiey are able to withstand nnich higher 

 tempi-ratin-es. 



In nj\2 the writer first suggested that lamziekte was a 

 disease belonging to thai class of deficiency diseases to which 

 scurvy and beri-beri had recently been proved to belong. Al- 

 th(»ugh this view has been discredited by Professor Hedinger. 

 who favoured a parasite, and Sir .Arnold Theiler, the writer is 

 still of tlie opinion that the disease will one day be classed among 

 the delicicncy di.seases. It would seem, too, tliat if atiximones 

 are what is claimed for them, then — 



