202 



TllK JOIRXAL OF HeRKDITY 



I notice these all show the (i. Russet 

 at the stem end. I have seen the blossom 

 end Russet. I may say the whole tree 

 does not produce all like the sample, 

 since the Russet predominates. The 

 fruit is not as large as it should be, for 

 the trees lack the necessary culture." 



The account gi\'en in this letter does 

 not agree altogether with that given in 

 Mr. Clarke's earlier letter, as to the 

 parent varieties. The earlier account 

 stated that Boston Stripe grafted on a 

 seedling gave rise to the parent tree; in 

 this account Boston Stripe is the stock 

 and Golden Russet the scion. It is 

 impossible at present to decide between 

 the two accounts. The photograph 

 shows very well the shar])ly marked 

 di\-ision of the apples into regions very 

 different in appearance. The stem end 

 of the apple was in each case of "russet" 

 and without stripes; the blossom end 

 was smooth skinned, of a light red color 

 striped with yellow or green (uncolored) . 

 When one of the apples was cut open 

 the flesh was found to be different in 

 texture and flavor in the two regions. 

 Underneath the russet skin the flesh 

 was coarser grained. One end of the 

 apple was distinctly sour, the other 

 insipid, almost sweet, but I neglected 

 to note which region was sour, the russet 

 or the striped portion, but I think the 

 former. The line of demarcation within 

 the flesh was sharp, as on the surface. 



Since the time when these "freak" 

 apples first came to my attention the 

 nature and origin of such plant creations 

 has been investigated with brilliant 

 success by Winkler and Baur in Ger- 

 manv. As a result we now call such 



things plant-chimeras, and we know that 

 they arise in consequence of grafting, 

 in cases wherein the original buds of 

 the scion have failed to grow, but an 

 adventitious bud has arisen exactly at 

 the junction of stock and scion and 

 including cells derived from both. 

 Each of these two kinds of cells rcj^ro- 

 duces its own sort, though the\' remain 

 side by side but quite distinct in the 

 same stem. 



Winkler has prodticcd several different 

 sorts of chimeras by grafting the tomato 

 (Solanirm lycopersicum) and the night- 

 shade (S. nigrum) one upon the other 

 and then decapitating the graft. In 

 some of these the stem is divided right 

 and left between tomato and night- 

 shade tissue, the stem on one side bear- 

 ing tomato leaves, on the other night- 

 shade leaves. Such plants are known 

 as sectorial chimeras. In other cases, 

 tomato cells form the one or two outer 

 layers of the entire ])lant, while under- 

 neath occur only nightshade cells; or 

 these relations may be exactly reversed. 

 Histological study fully confinns this 

 view. Such chimeras are known as 

 periclinal. 



In the apples figured the chimera 

 would seem to be sectorial rather than 

 periclinal, if the line of demarcation 

 ran lengthwise of the apple rather than 

 across it. But as it is, they resemble 

 more a periclinal chimera which has 

 everted its deeper lying tissue at the 

 blossom end of the fruit. Does the fruit 

 of the a])]:)le develo]) in that way? 

 Will such fruits gi\-e us a clue to the 

 answer' The\' ccrtainh- merit further 

 stud v. 



Galton's Law of Regression 



The law of regression tells heavil\- against the full heredilarx- transmission of 

 any gift. Only a few out of man\' children would be likel\- to dift'er from medioc- 

 rity as widely as their mid-]jarent, and still fewer would differ as widely as the 

 more exceptional of the two parents. The more bountifully the parent is gifted 

 by nature, the more rare will be his good fortune if he begets a son as richly endowed 

 as himself, and still more so if he has a son who is endowed yet more largely. But 

 the law is even handed; it levels an equal succession tax on the transmission of 

 badness as of goodness. If it di.scourages the extravagant hoi)es of a gifted parent 

 that his children will inherit all his ])owers, it no less discountenances extravagant 

 fears that thev will inherit all his weakness and disease. — Francis Galton; Natural 

 Inheritance (1889). 



