Lists Lusitanian shells with wide ranges beyond that geographical province.
Antiquity and elevation of land mass is more important than latitude for the distribution of shells.
Showing 41–60 of 69 items
Lists Lusitanian shells with wide ranges beyond that geographical province.
Antiquity and elevation of land mass is more important than latitude for the distribution of shells.
Responds to CD’s questions about the geographical distribution of freshwater fishes.
Believes intermediate varieties are generally less numerous in individuals than the two states that they connect.
Discusses the difficulties of deciding what is the typical form of a species
and gives some opinions on the variability of introduced species compared with indigenous species.
One plant in self-sown patch of Aegilops has assumed a triticoidal character; JSH feels it may be an example of Aegilops passing to wheat.
JDH’s arguments against transmutation: 1. Plants do not show the confusion he would expect; 2. Under clearly similar physical conditions we do not find same species.
JDH’s argument against migration: commonality of alpine species. Believes migration opposes facts of botanical distribution in Van Diemen’s Land and New Zealand; prefers continental extension theory.
Responds to CD’s query about the blind fauna of Mammoth Cave.
Gives information from L. Agassiz. Distribution of Crustacea, especially along southern coastlines.
Reports on the naturalised animal life of Ascension.
C. T. Beke has communicated to the Mauritius Natural History Society a letter he received from CD. VdeR attempts to answer questions on transport of seeds by the ocean.
Plants that are social in the U. S. but are not so in the Old World.
Distribution of U. S. species common to Europe.
Gives Theodor Engelmann’s opinion on the relative variability of indigenous and introduced plants and notes the effects of man’s settlement on the numbers and distribution of indigenous plants.
Podostemaceae flowering under water.
Responds to CD’s queries on Sierra Leone: fertility of European animals introduced to W. Africa, relationship of health and complexion of Europeans, etc.
Outlines the ranges of northern U. S. species common to Europe. Hopes to investigate the resemblances between the floras of the north-eastern U. S. and western Europe. Discusses routes by which alpine plants appear to have reached U. S.
JDH approves MS section on geographical distribution.
Never felt so shaky about species before.
His objections to some mechanisms of distribution that CD proposes.
Greatly interested in CD’s experiments with seeds in salt water [see "Action of sea-water on seeds", Collected papers 1: 264–73]. Believes CD exaggerates the force of the objection, against migration, that seeds tend to sink.
Believes he can give CD information on Mammalia of St Thomas [São Tomé, Gulf of Guinea]. Quotes from a Portuguese history of the islands on unique species of monkeys and civet cats found there.
Discusses means of seed transport.
Considers the difficulty of deciding which, if any, botanical species are real.
Continued debate on formation of species as a result of retreat from glaciers.
JDH suggests internal powers of species modification, which he knows CD abhors.
He is not sure whether he has seen Subularia flowering above the water, but thinks it probably is an aerial flowerer, at least sometimes.
Has been unable to find an anonymous book on pigeons in the University Library.
The Kentucky cave insects (Adelops) are evidently identical to European species of the same genus, some of which are cave insects, others found in damp, dark places.
Responds to CD’s query on Subularia and Limosella. There are discrepancies among authorities on whether Subularia flowers out of water. Limosella certainly flowers out of water.