Ixvi 
Journal of Proceedings. 
careful search is made for them. I speak with confidence on this point, 
having recently found several of them. These Algae are probably brought 
to our shores by the ocean currents. Judging from the character of 
the species occurring on our coasts, I have been led to the conclusion 
that the warm water of the Gulf Stream brings southern weeds, including 
some Mediterranean species, to our southern and western shores, its 
influence extending as far as Folkestone to the east and the Orkneys to 
the north. In the opposite direction a cold current, bringing with it 
northern species, appears to descend from the north, and probably sinks 
beneath the warm water from the south when it meets it, both currents 
leaving Algas to settle and grow wherever there occurs a quiet land-locked 
bay into which they can be carried by an eddy. The cold current, 
apparently divided by the north of Scotland, seems to pass down both 
sides of England, being probably diverted from its course by the pro¬ 
jecting land of Wales on the west and Norfolk on the east. At least, I 
have not been able to trace such northern species as Odonthalia further 
south than Yorkshire, nor such southern ones as Cystoseira ericoides 
further north than Anglesea. This theory seems to be corroborated by 
the fact that several southern species of Lichens have been found on the 
coast of Anglesea, while the Foraminifera of the north-east of Britain 
have been found by Mr. H. B. Brady, F.R.S., to be identical with those 
of Norway. Having traced the northern Algae as far as the Wash, and 
the southern as far as Folkestone, it would be especially interesting to 
ascertain the character of those found on the Essex coast on the east and 
of the Welsh coast on the west, but of the Algae of these coasts there 
exist, I believe, very meagre records. That an investigation of the 
marine flora of Essex would prove very interesting I have but little 
doubt. While looking through the herbarium of the late Dr. Lands- 
borough I came across a specimen of a North American seaweed, Dasya 
elegans, labelled ‘ Thames River, February,’ but whether it was found 
on the Essex coast or not was not mentioned. The plants of this genus 
love muddy shores, and as this species is found also in the Mediterranean 
the question arises, is it a native of Britain, or was it merely brought 
here attached to a vessel which had remained some months in a foreign 
part? This question an investigation of the Marine Algte of Essex might 
settle. Almost the only other contribution I can offer to the Essex list of 
Marine Alga is Bostrychia Scorpio ides, an amphibious species occurring 
on the roots of Obione pedunculatci and other seaside plants, sometimes, 
as near the Isle of Portland, covering extensive pieces of ground. A spe¬ 
cimen of this plant I observed in the herbarium of the British Museum 
from Maldon, Essex. Although the plant occurs so abundantly, I am not 
aware that the capsular fruit has ever been found in this country.* 
“ It may be useful, perhaps, to call attention to those groups of Algae 
in which new British species are most likely to be discovered on Essex 
shores. On a comparison of the French flora with the English the prin¬ 
cipal genera which are less fully represented in this country appear 
to be Lyngbya, Oscillaria, Cladophora, Callithamnion, Polysiphonia, 
B do carpus, and Mesogloia. 
“ Of these genera I propose to give a brief sketch, such as may enable 
anyone unacquainted with our English species to know where to look 
for them, and to refer the plants to their respective genera when found. 
“There are probably few persons who have botanised along muddy 
creeks who have not noticed scattered here and there small patches 
having the appearance of dark green or bluish green slime, sometimes 
floating on marine plants and sometimes growing on the mud. If a 
* Some ripe capsules have been detected by Mr. Buff ham, since this paper was written, 
on specimens brought by me from Portland. 
