1 77 
O’ Brien . — The Proteids of Wheal. 
terminology in the subject and goes back to the position in 
which the matter was left by Taddei, gluten being resolved 
into zymom and gliadin [glian]. Though he rejects myxon 
as a distinct body, considering it but a mixture of Pflanzen- 
leim and gluten-particles, yet he does not consider gliadin to 
be a single substance. Its separation he effects by means of 
boiling water into: (i) a ‘leimartig’ substance, soluble in 
boiling water, and (2) a residue soluble only in alcohol. The 
former is richer in nitrogen (17-7 8°/ o ) than gliadin (i 5-88°/ o ), 
the residue is poorer (i4*io°/ o ). The latter seems very like 
what I have described as myxon ; the former seems to consist 
of glutine and mucine, for a part of it is soluble even in cold 
water. The important point seems to me to be this, that by 
the use of boiling water instead of boiling alcohol the division 
line between the soluble and insoluble parts of glian (never 
a hard and fast one) is now drawn at a different place. Un- 
fortunately, in this as in many other cases, no account is given 
of the proportion in which these different constituents appear 
in gluten. 
Ritthausen 22 may next be mentioned, for his researches go 
back beyond i860, though his complete results were only 
published in 1872. He thus classifies the proteids of 
seeds : 
1. Plant- Albumin. 
2. Plant- Casein a. Legumin. 
b. Gluten-casein [Zymom], 
c. Conglutin. 
3. Plant- Gelatine (Pflanzenleim) or Gluten-proteids. 
a. Gliadin or Pflanzenleim [Glutine]. 
b. Mucedin [Mucine]. 
c. Gluten-fibrin [Myxon], 
Whence it will be seen that he ignores the work of animal 
physiologists and hardly attempts to bring vegetable proteids 
into line with those of the animal kingdom : a position which 
he defends later (1877 24 ), insisting on the differences of ulti- 
mate chemical composition between the various vegetable 
proteids as well as between these and animal proteids. 
