Showing 21–40 of 44 items
The land shells, both fossil and recent, of Madeira and Porto Santo have features peculiar to them, so RTL would have no difficulty in identifying them.
No summary available.
No summary available.
CD writes as the Treasurer of the Down Coal and Clothing Club and the Down Friendly Club, requesting subscriptions.
JDH’s contempt for R. I. Murchison.
There is a Cyperus species and a Pteris species endemic to hot volcanoes of Ischia. Why are there no other migrators?
Congratulates JDH on receipt of Royal Medal.
CD gathering facts on aberrant genera of insects.
No summary available.
Fossil leaves from Disko Island.
JDH to begin working out the botanical geography of the polar sea.
Has not forgotten CD’s request on aberrant species.
Has taken a house on Richmond Hill.
No summary available.
Sends list of aberrant forms of Curculionidae.
Discusses in detail the artificiality of Carl Johan Schönherr’s classification. Sound generalisations about geographical distribution depend on sound classifications. Warns against putting too much faith in current catalogues.
Calculating small number of species in aberrant genera of insects and plants.
Joachim Barrande’s "Colonies", Élie de Beaumont’s "lines of Elevation", Forbes’s "Polarity" make CD despair, as these theories lead to conclusions opposite to CD’s from the same classes of facts.
George Bentham’s list of aberrant plant genera. JDH appended the number of species in each genus according to E. G. Steudel’s catalogue [Nomenclator botanicus (1840–1)] and according to JDH and Bentham.
JDH speculates on effect of splitting Australia longitudinally on distribution; it becomes an argument for new creations.
In response to CD’s query, HCW says he cannot supply "any list of species as the flora of a single and sterile soil". Suggests a possible source of information, and provides some figures for Britain, but these apply to diverse soils.
Sends a count of the number of species of flowering plants and ferns on the islands of Fayal and Flores in the Azores.
No summary available.
Discusses the transport of seeds by birds. William Thompson received letters on this subject from CD in 1848 and from Edward Forbes in 1850. Encloses copies of Thompson’s reply to Forbes’s letter of 23 Feb 1850 and of Thompson’s notes (1848–51) on transport of seeds by birds.
JDH’s "grand speech" on receiving the Royal Medal.
No summary available.
Is Bentham’s list of aberrant genera biased by exclusion of genera with many species?
JDH’s belief that Aquilegia varieties are one species is consistent with their great interfertility.
Bentham’s list of aberrant genera: CD’s worry that he eliminated large genera a priori is half right. He eliminated those large, anomalous genera that virtually constitute natural orders. JDH criticises CD’s tabulations of aberrants.
Difficulty of distinguishing affinity and analogy in plants.
