144 REPORT—1840. 
phureous waters, to a chemical origin, whilst Dr. Daubeny, in his 
Report on Mineral Waters, laid before the British Association at Bris- 
tol, maintains that this substance is in all cases an organic production. 
The existence of organic matter, with a definite form, was first pointed 
out by Willan, which was examined by Dillwyn, and referred to the 
vegetable kingdom under the name of Conferva nivea. This plant has 
been recorded as existing in the sulphureous waters of Harrowgate, 
and has been found by the author in the same kind of water at Askerne 
in Yorkshire. In its young state it answers to the character of the 
organic fibres described by Daubeny, and in a more mature state to 
the plant as described by Dillwyn. This plant is of exceeding rapid 
growth, appearing in water impregnated with sulphuretted hydrogen 
after standing for a few hours. It also rapidly decomposes, giving rise 
to secondary combinations which closely resemble the characters of 
glairine, as stated by Professor Anglada. In the waters of Harrow- 
gate, another species of Conferva abounds, which, in its structure, 
resembles the species of Oseillatoria ; it collects in large quantities 
around the sides of the wells, and with deposits of inorganic and ani- 
mal matters form layers of a dark green, white and rose colour. In 
decomposing, these plants give out a more powerful odour than the 
water itself, a circumstance which has probably given rise to the opinion 
that a sulphuret of azote exists in these waters. These plants seem 
peculiar to sulphureous waters, and probably have their existence de- 
termined by the suphuretted hydrogen they contain. 
In many places where sulphuretted hydrogen is given out, a deposit 
is frequently found at the bottom of the waters, varying from a light 
pink to a deep rose colour. These deposits are sometimes exceedingly 
abundant throughout a large district around Askerne, where sulphureous 
springs abound ; they are always found in water or sand, impregnated 
with sulphuretted hydrogen. On an examination being made of these 
deposits, they were found to be produced by two species of animalcula ; 
one oblong, with from two to ten or twelve stomachs about the z5355th 
of an inch long, the other having about the same number of stomachs, 
but much longer than the first, and having the motions of a Vibrio. 
The first resembles the Astasia hematodes of Ehrenberg, which he 
describes as having been found in Siberia, producing a blood-coloured 
deposit at the bottom of a lake, but does not appear to possess a tail, 
which is a character of the genus Astasia. These animalcules live in 
water artificially impregnated with sulphuretted hydrogen, but do not 
die immediately in fresh water. The author has never seen them 
naturally without sulphuretted hydrogen, and in many instances has 
detected this gas by their presence in places in which it would not 
have been previously suspected. 
On the Pollen and Vegetable Impregnation. By Dr. ALpRIDGE, 
of Dublin. 
The author having discovered that nitric and other inorganic and 
organic acids produced the dehiscence of pollen-grains, in the same 
