Changes caused on the Spectrum, &e. By T. Palmer. 233 
tell how much to attribute to the accumulative action of natural 
selection, and how much to the definite action of the conditions of 
life.” But to pursue the point somewhat further, and still to 
keep to our author, Mr. Darwin, in his new work, under the 
heading of “ Uniform colour of the flowers on plants self-fertilized, 
22 el 20 19 Ey es a / 16 15 14 13 
23 
Fic. 8. 
Litmus 
normal. 
=| 
Fra. 10. 
Litmus 
ilkaline, 
Fic. 8.—Lirmus NorMau. 
M. | | A. Observations, ° 
21°3 Centre 25). 565°5 | Class 2. Very black. 
20°7 indies cctin ats 509°0 | Shaded to this point; size 2:5. 
Fic. 9,—Lirmvus Acrp. 
21°2 Commencement a0} Shaded gradually to very black, 
20°0 3 % 039°0 general absorption of blue, &c. 
Fic. 10.—Lirmus ALKALINE. 
| 
some \e@entrel ss ia 570°0 ‘. : . pice .on 
a Ta ee Re 5190 \ Same as in Fig. 8; size 2°25. 
NRE 
and grown under similar conditions for several generations.” 
‘Time will not, however, permit me to give you his exact words, 
but I should strongly advise all my hearers to invest in that charm- 
ing book, which has now been out for some time, and is entitled 
‘Cross and Self Fertilization of Plants.’ Mr. Darwin, after-having 
