258 PROCEEDINGS OF SOCIETIES. [^oumS, EuTsS^ 
after the long drought. He had intended to bring these observations 
before the Society in a complete form, but has not hitherto found time 
to do so. He proposed to carry on observations during every month 
in the year, for the purpose of recording the average amount of solid 
matter deposited on a given area, and also, as far as possible, to ascer- 
tain the character of the deposits. The observations so far have shown, 
as might have been expected, that the dust in various localities, at 
different altitudes, and under other varying conditions, contained par- 
ticles differing in magnitude, appearance, and quantity for the same 
superficial area. In every instance molecular activity was abundant, 
but the animal life was very variable in amount, the largest number of 
moving organisms being in the dust collected at the lowest points — 
this was about five feet above the surface of the earth. This dust also 
contained the largest proportion in magnitude and quantity of vegetable 
matter. These observations also show that in thoroughfares where 
there are many animals engaged in the trafiic, the majority of the light 
dust which when disturbed, reaches the average height of five feet, or 
about the level of a foot-passenger's mouth, consists of a large proportion 
of vegetable matter, which has passed through the stomachs of animals, 
or which has suffered partial decomposition in some way or other. This 
is not an agreeable piece of information, but it is a fact. It shows the 
necessity, in a sanitary point of view, of the streets being well- watered 
before the scavengers are allowed to commence operations ; otherwise 
the light dust is only made to change its locality and is not properly 
removed. It is not pleasant to contemplate the possibility of germs of 
disease being wafted along with this decaying matter, and inhaled by 
those whose condition might be favourable for its development. The 
author hopes to bring the details of these observations before the 
Society at some future time. H. A. Hurst, Esq., read a paper on the 
" Flora of Gibraltar," in which he remarked on its great richness, 
comprising, as it does, in an area of about 1 1 square mile, 500 plants, 
being one half of those contained in the Cybele Hibernica, and one-third 
of the whole number enumerated as growing in the British Islands in 
the last ' London Catalogue.' 
Microscojncal and Natural Hi story Section. 
February 1st, 1869.— J. B. Dancer, F.E.A.S., President of the 
Section, in the chair. Dr. Alcock exhibited some objects from 
Australia, lent to him for the purpose by the Lower Mosley Street 
Natural History Society. They were presented to that Society by Mr. 
Albert McDonald, of Pioneer's Eest, on the River Mary, Queensland, 
and consisted of the skull of a native Australian, and a stone tomahawk 
which had been found in the ground by a neighbour of his, and at Mr. 
McDonald's request it had been furnished with a proper native handle 
by one of the blacks. It was a very interesting specimen, as genuine 
implements of this kind are now very rare in the country, the use of 
iron having quite superseded them. He also exhibited some of the 
ordinary weapons of the natives, a shield made of very light wood and 
painted by a native artist, two war-clubs or nulla-nullas (aboriginal 
