52 
MARINE FAUNA OF ST. ANDREWS. 
these forms by him and the late Mr. Hancock (one of the 
best minute anatomists this country has produced) will soon 
be published. The most abundant simple form is the Ascidia 
sordida of Alder and Hancock, which is thrown by storms 
on the West Sands in large numbers, attached to sea¬ 
weeds, sticks, shells, and other objects. A. intestinalis is also 
procured in this manner as well as between tide-marks; 
Pelonaia corrugata and Molgula arenosa , A. & H., affect deep 
water only, and rarely occur during storms. The compound 
forms are common under stones between tide-marks and in 
the laminarian region : but much yet remains to be done in 
this respect at St. Andrews. Though Ascidians on the ex¬ 
posed parts of the east coast of Scotland are for the most part 
rare in the laminarian region and between tide-marks, they 
are common in still muddy waters on the west coast and in the 
Hebrides, and in water which cannot but be slightly brackish, 
as at the head of Loch Portan near Lochmaddy, where they 
are both abundant and large; they are also numerous and 
large between tide-marks at Herm and in the rich waters 
around the Channel Islands, as well as in the Zetlandic 
voes. 
Cynthia echinata, L. (From the Minch.) 
