394 Scientific Intelligence. 
Hybrids. 4. The mixture and disproportion of the pri/nciples 
of reproduction of different individuals of the same species, 
give origin to races or varieties. 5. The forced action of one 
prineiple upon another in fecundation, ’when the elements of 
these principles belonging to different races have already un- 
dergone changes of organization, gives rise to monsters. 6 . Hy- 
brids, varieties and monsters, are therefore due to the seed only, 
7. The seed equally gives origin to the domestic and wild va- 
rieties. 8. Culture has destined the first of these to provide 
grafts, the second to bear them. 9. Grafts or sets only can per- 
petuate these varieties in their natural state. 10. The seeds of 
these varieties are themselves, however, subject to the influence 
of fecundation, and capable of producing new varieties, either 
better or worse in kind. These afford types, when the fecun- 
dation takes place naturally. 11. Monsters are individuals, the 
organization of which has undergone a change in the process of 
fecundation. 12. If this change takes place in the ovary ^ the 
monstrosity is in the fruit which results from it, and perishes with 
it. 13. The monster is regularly sterile^ or semi-sterile ; either 
by the nature of the flowers, which either have not sex, or have 
only the female organ, or too small a proportion of the male ; or 
by the nature of the fruit, which is either entirely without seedy 
or which has only sterile or abortive seed, or too little seed^ 
Whence, it rarely happens that monsters can be multiplied by 
reproduction ; but either grafting or sets are required for this- 
purpose. 
34. Dr John on Potash in Vegetables^ ^c. — In Prdfessor 
John of Berlin’s Prize Essay, published in Berlin in 1819, On 
the Origin of Alkali and other Salts in Vegetables,” we find the 
following factSi 1. Uncombined potash does not occur in living 
vegetables, it being always combined with an acid, and is only 
found in them when they are in a state of putridity or decom- 
position, 2. Plants that feel rough and sharp, particularly 
equiseti, contain much siliceous earth ; in the latter fully 13 per 
cent. 3. Lichens that grow on the summits of fir trees, contain 
an uncommon proportion of oxide of iron, which. Dr John re- 
marks, may be viewed as illustrative of the formation of iron by 
the vegetable process. 4. Dr John recommends the use of de- 
caying and diseased wood to those who wish to obtain potash 
