rilKMK AL BASIS OF THF. ANIMAL BOO 



only .slightly soluble. in water, but readily soluble in . 

 which property tin- two pigments ailiuit of being sepai 



uithose is crystalline, soluble in alcohol ami oEloxofonil, is 

 coloured red ly acids and violet liy alkalis. Since pyoxan; 

 appears to In- a product of tin- decomposition of pyocyanin, both 

 pigments may oceur simultaneously in pus. in which cast- the 

 fluid is green. According to some more r.-c.-nt dboen 

 eyanin, as judged of by its reactions with tin- chlorides ot 

 jilatiniun and with other alkaloidal jin-i-ijiitants, as also from tin- 

 t'onnatioii of crystalline compounds with acids, is closely ivhu 

 tin- alkaloids. 



Sweat is also occasionally coloured blue, in some cases by in- 

 dii:<>-blue (p. 200) as in urine, and it may be (?) by a pigment 

 similar to pyocyanin. 



i if (I,,- suprarenal bodies. A suprarenal body when a 

 11 is made through it is found to consist of an outer i 

 eal portion, of a yellow colour, which constitutes the chief jKirt i 



: rnetuiv, and an inner, medullary part of a darker colour. 

 When the latter is acted upon by ferric chloride it assuu 

 dark bluish- or greenish-black colour, and if an aqueous ev 

 ot' its substance (or the tissue itself) be treated with an o\idi>ing 

 a-ent it turns red ( 498). It appears therefore that the >upru- 

 ivnals contain some form of chromogen or pigment-forerunner 

 which gives rise under appropriate conditions to a pigment 

 cording to some observers extracts of the cortex show a spectrum 

 similar to that of the histohaematins (p. 234) while the medulla 

 gives one resembling hivmochromogen. 2 The pigment obtainable 

 from the suprarenals has been investigated by Erokenbeig. 1 By 

 a method for which the original paper must be consulted. 1 

 lated a brownish-red substance with an acid reaction, soluble in 

 water and alcohol, whose reactions were the same as those oi 



s of the suprareuals. None of the solutions showed any dis- 

 tinct absorption bands. The whole subject requires fuither 



-libation, which mi.uht be of interest in connection with the 

 origin and causation of the incivacsd pigmentation of the skin ob- 



d when the suprarenals are diseased. 



-ard, Comitt. fond. T. xnv. (1882), j. 



1C MIIIIII. /' / IH84 (Jl. ofPftyiiol. Vol. T. p. \ 



Artk. IM. < i (1886), > 54a. 



