1. It is no longer a difference in degrees of maturity,for all the trees have darkened to their final tone,and stand in their differences of character and not of mere date.
解析:本句的主干為:It is no longer a difference。介詞短語in degrees of maturity作狀語限定difference的范圍;difference in…意為“在…(方面)的差異”。For引導原因狀語從句，該從句包含兩個并列的謂語（have darkened to…,and stand…）;not of mere date中間省略了成分，補充完整即是not in their differences of mere date。

2. It has a darkened and a daily color,in majestic but not obvious harmony with dark grey skies,and might look, to inconstant eyes,as prosaic after spring as eleven o'clock looks after the dawn.
解析:本句有兩個并列的謂語，主干為:It has a…color,and might look…as prosaic。介詞短語in…harmony with…作狀語表方式，該短語意為“與…十分協調”；but not意為“而不是”。To inconstant eyes是介詞短語，to在此處作介詞而不是不定式，表示“對于”。句末為“as…as”的結構，意為“像…一樣”。