336 The Scope and Provinces of Zoology. [June, 
Potassium chromate and bichromate are about equal in 
their action on sweet peas. Both colour the petals 
strongly. 
Ferrocyanide and ferricyanide of potassium are equal in 
their action, and do not differ appreciably in destructiveness 
from the chromate and bichromate. Both colour the petals, 
the tint being the same in both. 
Cyanide and sulphocyanide of potassium do not differ one 
from another with regard to their action on sweet peas, but 
are more hurtful than the chromates and ferrocyanides. 
The salts of iron seem very hurtful to the life of sweet 
peas, more especially the protosulphate of iron. Both 
colour the petals, the colour being brownish black. The 
ferrous sulphate colours the petals more strongly than the 
ferric, and kills the flowers sooner. 
Strontium nitrate and barium chloride are less hurtful than 
the chromates ; the ferro-cyanides and the cyanides also 
much less hurtful than salts of iron and zinc. 
Oxalate of ammonia is more destructive to sweet peas 
than sulphate of zinc or sulphite of soda. 
Of copper sulphate, mercuric chloride, arseniate of soda, 
and acetate of lead, the least hurtful is mercuric chloride, 
the flowers remaining quite fresh for eight hours sometimes. 
Arseniate of soda is the least hurtful, while lead acetate and 
copper sulphate seemed to be equal in their effect and less 
hurtful than arseniate of soda. 
VI. HAECKEL, HUXLEY, AND MIVART ON 
THE SCOPE AND PROVINCES OF ZOOLOGY. 
By Oswald Dawson. 
8 PROFESSOR HAECKEL, in a volume recently con- 
^ tributed to the International Library of Science and 
Freethought, appends to an address delivered at Jena 
University in 1869, and thrice published in Germany since 
that year, a table illustrating the scope of zoology which 
contains several words differing from, or foreign to, those 
