VEGETABLE PROTEIDS. 53 
yolks of fishes' eggs, and termed by them Lchthin, ichthulin, and emydin, are 
regarded by Koppe-Seyleras doubtful chemical units, and are probably mixtures 
of vitelliu with nuclein andlecithin. Whether vitellin contains phosphorus in 
its molecule or uol is a mool point. Some regard it as a nucleo-proteid rather 
than a globulin; others look upon the phosphorus generally found in it as 
belonging to either nuclein or lecithin, adherent to it as an impurity. The 
same question arises in connection with phytovitellin (vegetable vitellin). 
Recent analyses by Osborne 1 show that it contains no phosphorus, though 
Sachsse, one of the earlier workers, described the presence of this element. 
Proteids of flours. — Sidney Martin- found the principal proteids in wheat 
flour to be (1) a vegetable myosin, and (2) a soluble proteose, which he 
called phytalbumose. 
Gluten is a mixture of two substances — 
(a) Gluten fibrin, which is insoluble in alcohol, and formed from the 
myosin ; and 
(b) A proteose insoluble in water, formed from the phytalbumose. This 
Fig. 11.— Crystallised vitellin of the oat kernel. — After Osborne. 
insoluble proteose is, however, soluble in strong alcohol, and gives the sticky 
consistency to gluten ; it corresponds to the two substances called gliadin and 
mucedin by Ritthausen. 3 
The existence of proteids soluble in strong, though probably not in abso- 
lute, alcohol, is a remarkable occurrence, and is not unique in vegetable 
physiology. 
Martin considered that gluten does not pre-exist in wheat-flour, but is 
formed on the addition of water by a ferment action. This is supported by 
the fact that washing flour with water at a low temperature (2° C.) does not 
lead to the formation of gluten. The ferment, however, has not been 
separated, and Johannsen i has advanced certain facts that tell against the 
ferment theory and in favour of the pre-existence of gluten in the flour. 
1 Am. Limn. Joum., Baltimore, vol. xiv. ~No. 8. 
-Brit. Med. Joum., London, 1886, vol. ii. p. 104. 
8 Joum. f. prakt. Chem., Leipzig, Bel. lxxiv. S. 193, 384. For other observations on 
gluten, see Bouchardat, Oompt. rend. Acad. d. se., Paris, tome xiv. p. r>o'2 : Taddei, Gior. 
fisica ill Brugnatelli, vol. xii. p. 860; Gunsberg. Joum. f. prakt. Chem., Leipzig, Bd. 
lxxxv. S. 213. 
4 Ann. agronomiques, Taris, tome xiv. p. 420, 
