MARINE BIOLOGICAL STATION ON PUFFIN ISLAND, 23 
‘ at all, for 1t to extricate itself; and one in which the shell 
was so jammed in between projecting points of rock round 
which it was moulded, that I was not able even with the 
careful use of a strong knife-blade to get the shell out 
entire. Whether the limpet is sometimes able to obtain 
sufficient food by raising slightly the edges of its shell I 
cannot say, but certainly the last few cases mentioned 
seem to prove that individuals now and then fix themselves 
in positions which after a time they cannot leave on 
account of the growth of their shells. 
For the rest, our programme at Puffin Island was much 
as usual. We bathed about 7.30 a.m., and collected 
specimens on the rocks at low tide for an hour or so before 
breakfast; Mr. Thompson took tow-nettings from the 
punt round the shore, and Mr. Leicester searched the 
cliffs and the bushes for land mollusca. We examined 
into the condition of the boats, the rain gutters on the 
roof, and the water cistern, and made arrangements for 
the necessary repairs. Finally, we gave instructions to 
the new keeper in regard to the tinned meats and other 
stores to be laid in, and the best way of providing meals 
for the biologists who might be going down to work at the 
station during the Haster vacation. 
One noticeable feature of the shore at this time was that 
the specimens of Littorina rudis, which are so very abun- 
dant in summer and autumn on the rocks above high 
water mark, were now almost entirely absent. The only 
ones left were a few odd individuals down at bottom of 
deep clefts and crevices, perhaps unable to get out. 
On April 8th, Dr. Hanitsch went down to Puffin Island 
to work at Sponges. He obtained Tethya lyncuriwm and 
Raspatlia ventilabrum which had not been found on the 
island before and also three other species new to the dis- 
