264 Maternal Characters in Seeds [CH. 



instance in the " Mummy-pea" of our gardens. The 

 difference between these two is that the purple has the 

 blueing factor which in discussing Sweet Peas &c. we have 

 called B, and there can thus scarcely be a doubt that this 

 B factor is the complement of the indenting factor which 

 here came in from the pink side. 



Analogous observations have been made in regard to 

 Maize, especially by Lock. According as the seeds are 

 opaque or semi-transparent, the varieties are distinguished 

 as "Dent" or " Flint." These distinctions are also maternal 

 characters, and though segregation is normal, its effects 

 cannot be seen by examining the cob of F z seeds. Con- 

 ditions however, in particular the degree of ripeness, cause 

 a complication in this case, for the seeds, at the top and 

 bottom especially, may remain comparatively flinty after the 

 rest have assumed the dent character. 



In Wheat the relation between hard and soft endo- 

 sperms is probably similar, but Professor Biffen tells me 

 that in that case also complications occur. 



This group of cases introduces us to several points of 

 interest. We have first the remarkable fact that the mother- 

 plant can impress varietal characters on her offspring by 

 influences which are not heredity in the ordinary sense. 

 Seeds are in botany what larvae are in zoology, and no 

 example is yet known in which the maternal impress extends 

 beyond the seed-stage. But without any serious stretch of 

 imagination we may suppose that a maternal impress may 

 be such as to produce an effect lasting at least for the life- 

 time of the immediate offspring ; and it would not be 

 altogether surprising if such results were actually detected 

 in the cases enumerated ; for the difference in food-materials 

 between those provided by a dent seed and a flint, a 

 glutenous and a starchy, may, for aught we know, influence 

 the later life of the plant, just as the nature of the milk 

 supplied to the human infant is believed to do. Such 

 influences may probably enough be limited and perhaps 

 trifling in comparison with those that are in the strict 

 sense genetic, but we do not yet know that they are neg- 

 ligible. 



