1847.] Brand in the Cereals. 119 



fine Avarts, while at the same time the little oil-drops visibly in- 

 crease in the space of the spore-skin, and finally flow into a com- 

 pact yet scarcely iliscernible body, (Fig. 10). 



But it'wethoroughly examine theripe sporesof brand, and wehap- 

 pen to obtain good sections of the same — a problem extremely dif- 

 ficult on account of the minuteness of the body to be cut, and only to 

 be secured by chance — then we see that the spore-skin (Figs. 11, 

 12, t, t), of the brand-spore forms a dark colored single membrane 

 uneven on the outer surface, which encloses in its hollow space a 

 second transparent cell (Figs. 11, 12, 13, u, u, u), which forms 

 the second or inner spore-skin. But in the space of the second 

 spore skin we find a waxy, curved body (Figs. 11, 13, v, v), 

 which is called the kernel of the spore, and which in spores not 

 yet fully ripe, appears to be surrounded with little drops of oil. 

 The spores compared to other of the different kinds of brand 

 are large and their linear diameter is from 0.000700 to 0.- 

 000730 ( ttW ) <^' '^ Paris inch. The spores distinguish this spe- 

 cies of brand from all others which habitate wheat, and their spe- 

 cific gravity is greater than that of water; they sink therefore in 

 water, and hence the seed which is affected by brand may be 

 cleaned with running water, as it is thus also clear that well 

 washed seed suffJers less from the brand. But the seed must be 

 thoroughly washed before sowing, in order that the spores of 

 the brand, which may still be in the furrow of the seed and among 

 the chaff-hairs of the head, may be removed. 



Here is not the place to quote all the various opinions of the 

 husbandmen and natural historians respecting the existence and 

 propagation of the brand in the various kinds of grain generally. 

 The conviction and view of every individual is so peculiar a mat- 

 ter which rests on such difTerent grounds of representation and 

 positive induction, that opposition to even the crudest ideas (and 

 so called experience), according to my multifarious observation, 

 is only injurious. 



Yet I may be allowed to maintain here as preliminary, that the 

 view which regards the brand merely as a stage of disease, or a 

 disease analogous to the organic diseases of the animals, must in- 

 deed be false. 1 can only compare the parasitic formations which 

 belong to the class of fungi or mushrooms, to thephticiases or the 

 louse disease, and in this case no spcntaneous generatian is sup- 

 posed. We have one of the most decisive proofs in the case of a 

 majority of exotic plants which are evidently produced from seed 

 and no parasites (especially eutophytes) have been imported from 

 their native country, while in our glasshouse all the plants known 

 to me as having been brought alive from the tropic have introduced 

 certain eutophytes peculiar each to its species of plants, and not 



