181 
Thus when the latex of Hevea brasiliensis is held in the smoke 
of the burning urucuri nuts, the albumin it contains* is clotted by 
the action of heat in the presence of dilute acetic acid. 
The globulin of. Manihot Glaziovii latex diui pe on heating 
when the temperature rises to 74—76? C, 
The acid latex of Castilloa elastica contains an gae albumin, 
which on neutralization forms a gelatinous precipita 
These coagula on forming gather up the Pa Pertot icles (and 
probably starch -grainsalso,in the c eof starch-containing latices) i in 
the same way as the white-of-egg putida up particles in suspensio 
when clotted for the purpose of clearing jellies. e may even 
push the old analogy of blood and latex further, and compare the 
formation of a rubber-clot, in many cases, to the formation of 
blood-clot, the rubber-particles being bound together by coagulated 
proteids in the same way as the blood-corpuscles are "bound 
together by fibrin. In this case, however, we must remember 
iir d 
are, are bro ped of aggregating together of their own accord to 
form a solid 
Rubber then, as now prepared, -— among other Weinen 
proteid matters. wed these must be ribed the well-knoy 
‘fermentative chan which causes a id siderable loss by con- 
verting the solid blocs of rubber into a foul-smelling spongy 
substance, In the Para rubber the creosote absorbed from the 
smoke of the burning nuts acts as an antiseptic and now ents 
this proteid decomposition 
o test for the coagulated ‘Laden is not an easy matter ; 
continued boiling with a concentrated solution of caustic potash 
will, however, extract small quasi titios of alkali-albumin. ‘ Balata ' 
dete good results most readily. On extraction with caustic 
tash a flocculent precipitate is obtained, which is readily 
soluble in dilute n itric acid, and is  reprecipitated EX the am 
ali i a 
pue 
R. H. BIFFEN. 
Botanical Laboratory, Cambridge. 
February, 1898. 
DCXVIL.—KENDIR FIBRE. 
(Apocynum venetum, Linn.) 
In November, 1896, a letter was received from the Foreign 
BF n used in the manufacture of Russian paper money. With 
the report a packet of the seed of the plant was received. 
araday—see Le Caoutchouc et la gutta-percha, 
+a. R. Green, ibid. 
1 Cf. the smoking of fish, &c., for preserving purposes. 
