interested me much, and rather grieved me, for I had hoped things had been
in a slight degree otherwise. (40/1. "On certain Zoological Arguments
commonly adduced in favour of the hypothesis of the Progressive Development
of Animal Life," Discourse, Friday, April 20, 1855: "Proceedings R.I."
(1855). Published also in "Huxley's Scientific Memoirs." The lecturer
dwelt chiefly on the argument of Agassiz, which he summarises as follows:
"Homocercal fishes have in their embryonic state heterocercal tails;
therefore heterocercality is, so far, a mark of an embryonic state as
compared with homocercality, and the earlier heterocercal fish are
embryonic as compared with the later homocercal." He shows that facts do
not support this view, and concludes generally "that there is no real
parallel between the successive forms assumed in the development of the
life of the individual at present and those which have appeared at
different epochs in the past.") I heard some time ago that before long I
might congratulate you on becoming a married man. (40/2. Mr. Huxley was
married July 21st, 1855.) From my own experience of some fifteen years, I
am very sure that there is nothing in this wide world which more deserves
congratulation, and most sincerely and heartily do I congratulate you, and
wish you many years of as much happiness as this world can afford.


LETTER 41. TO J.D. HOOKER.

(41/1. The following letter illustrates Darwin's work on aberrant genera.
In the "Origin," Edition I., page 429, he wrote: "The more aberrant any
form is, the greater must be the number of connecting forms which, on my
theory, have been exterminated and utterly lost. And we have some evidence
of aberrant forms having suffered severely from extinction, for they are
generally represented by extremely few species; and such species as do
occur are generally very distinct from each other, which again implies