Summary

Has read FM’s paper on sponges ["Über Darwinella aurea", Arch. Miskrosk. Anat. 1 (1865): 344–53] with interest.

Has also read FM’s work on the metamorphoses of Peneus [Ann. & Mag. Nat. Hist. 3d ser. 14 (1864): 104–15], an interesting and important embryological discovery.

CD regards Louis Agassiz’s opinions as valueless.

Summary

Thanks CD for Journal of researches.

Insect genus Elater is an exception to the rule that all luminous organs give out a green light.

Gives some observations on climbing plants at Itajahy.

His study of orchids has convinced him of the value of CD’s book.

Summary

Thanks CD for German translation of Origin.

Droughts over the summers have brought about changes in the numbers of plants and animals in the area. The small quantity of Orchestia darwinii that has survived the changes no longer includes two previously common male forms. Great changes also take place without such unusual physical conditions. The disappearance of a briefly abundant bryozoan in local caves has made way not for the return of original bryozoan inhabitants but for a completely new fauna.

Summary

Structure of Scaevola and its fertilisation with insect aid.

Fertilisation of Aristolochia.

FM’s paper on climbing plants [see 5146].

Is preparing new edition of Origin.

Summary

Thanks for information on orchids

and facts on coastal flora and fauna.

Asks FM to look out for dimorphic aquatic and marsh plants.

Has read pamphlets "in our favour" by Carl v. Nägeli and Oscar Schmidt.

Summary

Gives some observations on orchids and on some plants which seem to be dichogamous.

Summary

Thanks for observations on orchids.

FM’s paper on climbing plants [see 5146]; CD has received proofs.

Carl Claus’s pamphlet on copepods [Die Copepodenfauna von Nizza (1866)].

Summary

Fertilisation in orchids: Friedrich Hildebrand’s paper.

Self-sterility.

Climbing plants.

Agassiz’s attempts to eliminate all Darwinian views.

Summary

Discusses dimorphism of Oxalis; one form has 99% sterile anthers. Has found three kinds of fertile anthers.

Summary

Hildebrand’s paper on trimorphism in Oxalis ["Über den Trimorphismus in der Gattung Oxalis", Monatsber. K. Preuss. Akad. Wiss. Berlin (1866): 352–74].

Problems of explaining brightly coloured, attractive seeds.

Haeckel has visited Down.

FM’s climbing plants paper is printed [J. Proc. Linn. Soc. Lond. (Bot.) 9 (1867): 344–9].

Summary

Sends his observations on sterility of Eschscholzia,

on Oxalis,

and on recently found dimorphic plants.

Sends specimen of Hedyotis [see Forms of flowers, p. 133].

Summary

Gives observations on orchid ovules ripening long after blooming.

Infertility with own pollen sometimes does and sometimes does not indicate dimorphism; gives observations on Ximenia, Eschscholtzia and Oncidium flexuosum.

Describes some striking seeds eaten by birds,

and some new dimorphic species.

Variation in Thillia.

Confirms CD’s suspicion that the lancet-fish [Amphioxus] lives in competition with invertebrates: it shares its habitat with a similar-looking Ophelia, which is quite unlike other annelids, just as the lancet-fish is unlike other fishes.

Summary

Thanks for observations on dimorphic plants. Dimorphism prevalent in certain groups throughout the world.

Retarded fertilisation in certain orchids.