novels a Professor Long, who had written two huge volumes on
limpets.

Although I was employed during eight years on this work, yet I
record in my diary that about two years out of this time was lost
by illness. On this account I went in 1848 for some months to
Malvern for hydropathic treatment, which did me much good, so
that on my return home I was able to resume work. So much was I
out of health that when my dear father died on November 13th,
1848, I was unable to attend his funeral or to act as one of his
executors.

My work on the Cirripedia possesses, I think, considerable value,
as besides describing several new and remarkable forms, I made
out the homologies of the various parts--I discovered the
cementing apparatus, though I blundered dreadfully about the
cement glands--and lastly I proved the existence in certain
genera of minute males complemental to and parasitic on the
hermaphrodites. This latter discovery has at last been fully
confirmed; though at one time a German writer was pleased to
attribute the whole account to my fertile imagination. The
Cirripedes form a highly varying and difficult group of species
to class; and my work was of considerable use to me, when I had
to discuss in the 'Origin of Species' the principles of a natural
classification. Nevertheless, I doubt whether the work was worth
the consumption of so much time.

>From September 1854 I devoted my whole time to arranging my huge
pile of notes, to observing, and to experimenting in relation to
the transmutation of species. During the voyage of the "Beagle"