[The year 1874 was given up to ‘Insectivorous Plants,’ with the exception of the months devoted to the second edition of the ‘Descent of Man,’ (see Vol. III. p. 175) and with the further exception of the time given to a second edition of his ‘Coral Reefs’ (1874). The Preface to the latter states that new facts have been added, the whole book revised, and “the latter chapters almost rewritten.” In the Appendix some account is given of Professor Semper's objections, and this was the occasion of correspondence between that naturalist and my father. In Professor Semper's volume, ‘Animal Life’ (one of the International Series), the author calls attention to the subject in the following passage which I give in German, the published English translation being, as it seems to me, incorrect: “Es scheint mir als ob er in der zweiten Ausgabe seines allgemein bekannten Werks iiber Korallenriffe einem Irrthume iiber meine Beobachtungen zum Opfer gefallen ist, indem er die Angaben, die ich allerdings bisher immer nur sehr kurz gehalten hatte, vollständig falsch wiedergegeben hat.”

The proof-sheets containing this passage were sent by Professor Semper to my father before ‘Animal Life’ was published, and this was the occasion for the following letter, which was afterwards published in Professor Semper's book.]