114 
LICHENES. 
sixty species and varieties, probably the first compiled for the 
district, will prove a valuable nucleus, which we trust may be 
speedily followed by a complete Lichen Flora of the island. 
The Rev. W. Johnson, F.L.S., a well-known lichenologist, 
announces that he is preparing to issue a few copies of “ A North 
of England Lichen Herbarium,” containing specimens from the 
counties of Cumberland, Durham, and Northumberland. For 
particulars address, Rev. W. Johnson, Shildon, via Darlington, 
Durham. 
New or Critical British Alg^e. 
By E. A. L. Batters, B.A., LL.B., F.L.S. 
Uxospoxa collabene, Holmes et Batters Annal. of Bot ., Vol. v., p. 73. 
Conferva collabens, Phyc. Brit., p. 327. Ulothrix collabens, Thur. 
in Lee Jol. Alg. ; Cherb. No. 159. 
I have received some beautiful specimens of this very rare 
British species from Mr. David Robertson, the veteran naturalist 
of Cumbrae, who has done so much for the flora and fauna of the 
Clyde sea-area. 
The plant was found at the end of last March, growing in 
company with Ulothrix Jlacca and Urospora isogona on a wooden 
buoy in the little harbour of Cumbrae. 
It grew in large slippery tufts of a clear glossy green colour. 
The filaments are from 3 to 5 inches long, the cells, varying in 
diameter from 70-450 p, and from 100-700 p in length, are of 
very various shapes and sizes. I have seen in the same filament a 
nearly globular cell 200 p in diameter, followed by an oblong one 
7 00 p long by 200 p wide. Usually the cells are cylindrical, and 
from once and a half to twice as long as broad below, and oval, 
globular, or oblong, very much constricted at the joints above. 
The following measurements were taken from a fertile filament 
from the middle of a tuft : — Cells at base 100 p long by 120 p 
wide, in the middle of the filament 400 p long by 220 p wide, 
while a few cells below the apex, to which the filament slightly 
tapered, 500 p long by 370 p in diameter. 
Mr. Robertson very kindly sent me some fresh specimens in a 
tube of sea water, and I was able to watch the exit of the zoo- 
spores. I saw both the elongated zoospores prolonged at one end 
into a long point, while the four cilia are situated at the other 
broader end, and the smaller more oval form. The former were 
large — about 24 p long by 9 or 10 p at the broad end, but in every 
way resembled the swarmspores of the other species of the genus 
Urospora. There are several nuclei and pyrenoids in each cell, 
