Summary

Problems of continuing with his crossing experiments; financial help from CD.

Summary

Gives the results of crossing experiments; some interesting and curious facts.

Summary

Tendril plants received.

Has just completed large crossing experiment with Lythrum.

Summary

Thanks AG for his criticisms of CD’s views; finds it difficult to avoid using the term "natural selection" as an agent.

Discusses crossing in Fumaria and barnacles.

Has received a naturally crossed kidney bean in which the seed-coat has been affected by the pollen of the fertilising plant.

Finds the rule of large genera having most varieties holds good and regards it as most important for his "principle of divergence".

Summary

Reports two observations on crossing in dogs: the preservation of both pure types in the offspring of a pointer and a setter, and the influence of a first mating with a mongrel on the progeny of a Barbary bitch and a subsequent Barbary male.

Summary

Thanks for notes on Cypripedium and Platanthera hookeri, which is really beautiful and quite a new case.

His son, George, has been observing the insect fertilisation of orchids.

CD has been crossing peloric flowers of Pelargonium, but doubts he will get good results with respect to sterility of hybrids.

Rhexia glandulosa does not appear to be dimorphic. Lythrum is trimorphic.

Summary

Discusses the reasons for inserting questions on consanguineous marriages in the forthcoming Census.

Summary

Thanks for AG’s remarks on disjoined species. CD’s notions are based on belief that disjoined species have suffered much extinction, which is the common cause of small genera and disjoined ranges.

Discusses out-crossing in plants.

Has failed to meet with a detailed account of regular and normal impregnation in the bud. Podostemon, Subularia, and underwater Leguminosae are the strongest cases against him.

Summary

On the "doubtful & obscure" subject of marriage of cousins, CD believes, that judging from the analogy of animals, no direct evil would follow from their marriage. He would, however, expect the offspring of unrelated parents to be somewhat superior in size and vigour. The injury from the increase of any bad tendency common to the family seems to CD more to be feared than mere consanguinity; "the good effects of crossing distinct families I look at as great & undoubted".

Summary

Describes the difficulties of crossing papilionaceous flowers. Believes the lack of success is a consequence of the need for early castration and successive applications of pollen on the stigma. Gives details of a method he has used to cross such flowers successfully.

Summary

Remarks on the influence of pollen of one species or variety on the seed and fruit of another while still attached to the female plant. Refers to a remarkable case previously given by D. Beaton and asks whether Beaton will repeat the details.

[CD’s letter is followed by notes by D. Beaton in which he answers CD’s question, dissociating himself from some of his remarks, and in particular denying C. F. v. Gärtner’s claim that colour of one variety of pea can be changed by the direct action of the pollen of a different variety.]

Summary

Thanks for informative letter of 2 February. CD is glad to have CVN’s opinion on the crossing of varieties of melons,

has made use of his memoir on the Cucurbitaceae ["Cucurbitacées cultivées au Muséum d’Histoire Naturelle en 1862", Ann. Sci. Nat. (Bot.) 18 (1863): 159–208]

and anticipates with great interest his work on hybridisation.

Summary

Discusses AG’s article ["Dimorphism", Am. J. Sci. 2d ser. 34 (1862): 419–20]. Does not like the terms "dioecio-dimorphism" or "precocious fertilisation". Discusses the separation of sexes in plants; cannot doubt that hermaphroditism is the aboriginal state.

Discusses AG’s observations on orchids and his review of Orchids [Am. J. Sci. 2d ser. 34 (1862): 138–51].

Summary

Observes Plantago’s out-crossing mechanism.

Observations of style lengths of primroses and cowslips.

Summary

CD finds JDH’s objections to a mundane cold period significant, and he endeavours to show how they do not rule out mutability.

He is writing on crossing.

Summary

Abstract will run into a small volume.

Urges JDH not to reject natural selection until he has read abstract.

[Enclosed are CD’s comments on a ?JDH manuscript that perhaps belong elsewhere.]

Summary

Discusses a crossing experiment.

Has been counting the seeds in pods [of Lythrum?].

Summary

CD is obliged for a note by JS on crossing the Victoria regia, just received from Hooker; encourages JS to further experiments, saying there is much to be learned on self-fertilisation of plants.

Summary

Orders seeds, ripened in Algiers; imported seed would be of no use. [Forwarded to Algiers by JDH, see 7272.]