MARINE BIOLOGICAL STATION ON PUFFIN ISLAND. 41 
1885, by Mr. Thompson from Puffin Island and the coast 
of North Wales, by Mr. Chadwick from Beaumaris, and 
by Mr. Shrubsole from Sheerness; and again, in 1886, in 
vol. i. of our “‘Fauna.”* This condition of the sea has 
since been met with by Prof. McIntosh in St. Andrew’s 
Bay, in 1887, and by the naturalists at the Plymouth 
Biological Station, in 1889. In 1885 and 1886, in our 
neighbourhood, the ‘foul water’? was caused by the 
presence of vast numbers of small gelatinous spherical 
bodies containing minute spicules. During the last few 
years, however, this form has not been observed here, its 
place being taken in early summer by gelatinous masses, 
which are found on examination to be composed almost 
entirely of Diatoms, chiefly Coscinodiscus concinnus. 
From the adjoining series of quotations from the weekly 
reports, it is seen that the temperature of the sea was at 
its lowest (40° F.) early in February, and from that date 
the temperature rose gradually till it reached its highest 
point (61° F.) early in August, and then commenced to fall. 
The surface Algee began to appear about the middle of 
May, when the temperature was 50° F., and continued to 
be present in great abundance for about six weeks, till 
near the end of June, and in less amount up to the 20th 
August, when they disappeared. After June, Medusze, 
Ctenophora, Copepoda and other surface organisms were 
present in great abundance. | 
When these minute Algz are present in quantity it is 
almost useless to tow-net, as the comparatively few other — 
organisms present in the water become so entangled with 
the masses of Diatoms that it is almost impossible to 
separate them. 
* «‘Hauna of Liverpool Bay,” vol. i., p. 315, 1886. 
+ Ann. and Mag. Nat. Hist., Aug.~1887, p. 97. 
+ Journ. Mar. Biol. Assoc., vol. i., No. 2, Oct. 1889, p. 114. 
