56 THE INVERTEBRATE FAUNA 
storms; they are probably what are referred 
to by Dr M‘Bain as Ascidia prunum. 
These young specimens are perfectly trans- 
parent, and have a beautiful crystalline 
appearance. They are excellent objects 
in which to study the circulation in the 
living animal. 
Ascidia depressa (Alder). 
| We obtained several specimens of this 
characteristic species, some years ago, at 
low water mark near Elie. 
A, scabra (O. F. Miller). 
This species we also obtained on the same 
occasion, near Elie, in considerable 
quantity. 
Ciona intestinalis (Linneus). 
This beautiful species is fairly common on 
the oyster bank, and on muddy bottoms 
elsewhere throughout the Firth ; it attains 
a large size. We have dredged it in 
various parts of the Firth, and have also 
taken it at low water mark at Elie and 
Aberdour, generally adhering to the roots 
of Laminaria. 
ASCIDILZ COMPOSIT. 
BotTrRYLLID. 
Botryllus schlossert (Pallas). 
This species is common at low water mark 
on the shores of the Firth. It is usually 
found on the under surface of large stones, 
or encrusting the roots and stems of 
Laminaria, Fucus, ete. 
We have taken it at Elie, North Berwick, 
Aberdour, and other localities. 
Dr M‘Bain records this species in his list. 
B. polycyclus (Savigny). 
This species appears to berarerthan thelast. 
