84 THE ESSEX NATURALIST
Mr. Syms showed a mole flea, Hystrichoprylla talpae Curtis, taken in a
mole's nest at Fairmead in Epping Forest recently; he also exhibited a
cat flea and a common flea for comparison.
Mr. Scourfield showed coloured lantern views of various entomostraca,
as Daphnia, Polyphemus and Latona, to illustrate remarks on the varying
degree of colour in these organisms due to the varying amount of haemo-
globin present.
The President exhibited a number of superb photomicrographs in illus-
tration of his account of "compression wood" in coniferous trees and of
its effect as a source of weakness in their timbers.
The meeting ended at 4.30 o'clock.
VISIT TO KEW HERBARIUM (868th Meeting)
SATURDAY, FEBRUARY 15TH, 1947
Fifteen members and two visitors braved the bitterly cold weather and
made their comfortless way to Kew to inspect the Herbarium ; here they
were welcomed by Mr. Ballard, who cheerfully devoted the whole afternoon
to the party.
The Herbarium is a very unobtrusive building standing behind its high
wall by the main gate to the Gardens but is, nevertheless, the largest her-
barium in the world. The idea of founding a national herbarium here was
first mooted in the reign of George III who, at the instigation of Sir Joseph
Banks, bought a house on Kew Green for the purpose. Unfortunately,
both king and naturalist died before much could be done. In 1830 the
house became the residence of William IV's brother, Ernest, Duke of
Cumberland, who left Kew after seven years to become King of Hanover.
Since then the house has been called "Hanover House."
In 1841 the royal gardens were thrown open to the public, and William
Jackson Hooker, Professor of Botany in the University of Glasgow, was
appointed first Director; he soon restored to them the prestige they had
enjoyed among botanists in the time of Sir Joseph Banks. It was, however,
several years before he was given access to Hanover House, and even then
was allotted only two rooms. Here he housed his own library and her-
barium and used them as a nucleus for the national collection. Under
his administration the collection grew rapidly, and soon the whole building
was given over to its accommodation. Early in the present century two
new wings were added, and in 1930-1 a further extension, an all-metal wing
of pleasing modern design, was erected. Most fortunately no part of the
Herbarium sustained serious damage during the recent war, but again
expansion has become desirable.
Mr. Ballard described how the girls employed for the work mount the
specimens and explained the drastic measures taken to ward off insect and
fungus attack on the dried specimens. Before mounting, the plant is
"poisoned" by prolonged exposure to the deadly hydrocyanic acid gas.
After mounting, the girl "poisons" the plant a second time by painting it
with a solution containing corrosive sublimate; even then an occasional
grub appears and does a certain amount of damage. Six million sheets of
specimens take a great deal of looking after!
The question of recording colours of specimens had occurred to several
members, since, whether dried or preserved in fluid, plants lose their colours.
They were therefore interested to hear that nowadays specimens are often
sent in with descriptions of their colours standardised by reference to a
recognised colour-chart. Later, Mr. Ballard showed one of the charts, and
it was found to be very comprehensive in its range of colours and convenient
to use.