62 
activity is lost on boiling. As is evident from the work of Planehe ( 326 > 
327 ), Schoenbein, ( 377; 378 ‘ 383 ), and Bertrand ( 51 ), laccase or a guaiacum- 
bluing ferment of similar nature is almost universally distributed in 
the plant kingdom. Thus Bertrand found it in the tubers of the 
dahlia, in the potato, in the rhizome of the American reed, in the 
raeines of the beet and turnip, in the stalk of the asparagus, and in 
apples, pears, etc. As a matter of fact, there are certainly but com- 
paratively few of the higher fungi or of the chlorophyllous plants 
which do not blue guaiacum at least in certain of their tissues at 
certain stages of then development. 
It was believed at one time by Rey-Pailhade ( 342r 344 ) that animal 
tissues have not the power to blue guaiacum and that therefore they 
contain no laccase. Subsequent investigations, however, have shown 
that this is much too sweeping a generalization. Thus Biedermann ( R7 ) 
observed that an aqueous extract of the middle intestine of the starv- 
ing meal-worm gives an intense blue coloration with guaiacum. 
According to Giard ( 192 ), BotryUoides cyanescens and Ascidia fumigata, 
Grube, give an immediate and very intense blue color with tincture 
of guaiacum. The blood of the last-named ascidian was clear yellow 
when freshly drawn, becoming dark green on exposure to the air. 
Portier ( 33 °) has confirmed these observations on Ascidia mentula, 
and Abelous and Biarnes ( 6 ) have obtained similar results with the 
blood-plasma of the craw-fish. Similarly Pieri and Portier ( 324 ) have 
found a powerful oxidase in the gills and labial palps and blood of the 
acephalous molluscs, including the common oyster and the fresh- 
water species, Anadonta cygnea; this oxidase is said to give an 
intense blue coloration with guaiacum and to rapidly convert hydro- 
quinone into quinone and quinhydrone. Hougonenq and Paviot ( 22 °) 
claim to have found that certain malignant tumors give the guaiacum 
reaction; Cavazzani ( 113 ) has made experiments indicating the pres- 
ence of an oxidase in the cerebro-spinal fluid, which he has termed 
‘ ‘ Cerebro-spinase, and recently the brothers Lumlere and Chev- 
rotier ( 2S1 ) have prepared a protoplasmic extract of red blood cor- 
puscles to which they have given the name ‘ “ Hemoplase 7 ’ and which 
they claim possesses the properties of an oxidase to a remarkable 
degree, as shown by its power to oxidize guaiacum, guaiacol, para- 
phenylene diamin, pyrogallol, and hydroquinone. Gessard ( 185 ) has 
found laccase in the ink-gland of the cuttle-fish. 
While these observations are of interest as showing the occurrence 
of laccase or a similar guaiacum-bluing ferment in animal tissues and 
fluids, it is undoubtedly true that such ferments are of much rarer 
occurrence in animal than in plant tissues. At present the precise 
significance of this is onlv a matter of conjecture. It is interesting 
to note in this connection, however, that Ehrlich ( 157 ) found the tissues 
of the higher animals to possess powerful reducing properties, as „ 
indicated by their conduct toward methylene blue. It is quite' con- 
