Showing 21–40 of 48 items
Asks whether LJ can throw light on this subject: "What are the checks and what the periods of life by which the increase of any given species is limited?" CD has been driven to conclude that species are mutable; allied species are co-descendants from common stocks.
On checks to increase of species and the observations which led him to regard species as mutable in form. Would welcome "at some future time" LJ’s criticism of the "sketch" of his conclusions.
Discusses checks on growth of species population; use of term "mutation" in his species theory. His belief in species mutability.
Looks forward to LJ’s volume [Observations in natural history (1846)].
Observations on what the world would call trifling points in natural history are always very interesting to him. Deplores their absence in foreign periodicals.
Is slaving away to finish S. American geology.
Comments on LJ’s Observations [in natural history (1846)].
Discusses variation among British birds, and the conflicting treatment of bird species by C. W. L. Gloger and C. L. Brehm.
Describes collecting incident of his student days involving Carabus.
Mentions squirrels eating insects.
Astonished to hear of terrestrial Planaria.
Comments on BAAS meeting in Southampton.
Acknowledges receipt of [The naturalist’s pocket] almanack edited by LJ. Suggests some improvements.
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Thanks LJ for his book [Observations in meteorology (1858)].
CD has been working on his species book [Natural selection].
Has become dreadfully heterodox on immutability of species.
His work on pigeons: variation under domestication throws the greatest light on variation in a state of nature.
Asks LJ to lend him a copy of his paper ["Variation of species", Rep. BAAS 26 (1856): 101–5] and any notes or references he has. Although CD has a large accumulation of facts, it is impossible to see and consider too many.
His health is poor.
Thanks LJ for his MS [of "Variation of species", Rep. BAAS 26 (1856): 101–5].
Will read it at his hydropathic establishment [Moor Park], where he is going for a rest.
Returns MS [of "Variation of species"]; several facts were new to him, especially interested in wagtails.
Wishes he could swallow Florent Prévost on sparrows ["Du régime alimentaire des oiseaux", C. R. Hebd. Acad. Sci. 46 (1858): 136–8].
LJ’s facts seem to bear out CD’s conclusion that secondary sexual characters were most variable of all.
Explains how he intends to deal with variation, and general facts in natural history in the light of species theory. Can only afford one chapter on variation in nature. It seems more important to make out variation in domestic animals.
Asks for facts on birds’ nests for his chapter on instincts.