134 
MARINE FAUNA OF ST. ANDREWS. 
separated by the presence in considerable numbers of Cymodo- 
cea truncata and Spkceroma Prideauxianum in the fissures of 
rocks between tide-marks, and Dynamene in rock-pools. 
The characteristic Tanais vittatus , Parantliura cos tana, Noesa 
bidentata , Mcera grossimana , Chelura terebrans , Conilera cylin- 
drica , and the large Cymoihoa parasitic on the fishes at once 
distinguish the fauna of the Channel Islands from that at 
St. Andrews. The rarity of Orchestia littorea at the latter 
and its abundance in the tidal region of the Outer Hebrides, 
and the absence of Sidcator arenarius and its frequent occur¬ 
rence in the sand of the western shores of England, are also 
interesting contrasts. 
Many of the sessile-eyed Crustacea, such as Talitrus locusta , 
are extremely hardy. Gammarus locusta is often found in 
putrid localities, and it survives almost every other marine 
form in putrid vessels in confinement. The group as a whole 
is composed of extremely active animals ; and even the most 
grotesque, such as Caprella tuberculata, are at home in the 
intricacies of Geramium and other finely branched seaweeds. 
The boring forms (by jaws) are represented by Limnoria 
lignorum ; but its depredations are comparatively insignificant, 
probably because little wood is employed within water-mark in 
the construction of the harbour. The perforations of Talitrus , 
again, abound in the sand, and the looped burrows of Coro- 
phium in the sandy mud of the flats it inhabits. The nest¬ 
forming crustaceans are represented by A mphithoe podocer aides, 
Siphonoecetus typicus, Podocerus variegatus, and P.falcatus ; 
while the young of Gammarus locusta are often observed 
adhering to the abdominal region of the parent. 
The Cirripedes occur abundantly between tide-marks, the 
most conspicuous being Balanus balanoides , which covers 
the bare rocky ridges opposite the Castle and other parts. 
In deep water the various species are attached to shells, 
stones, crabs, wood, cork, coal, tests of ascidians, and other 
structures. 
I am indebted to Mr. Spence Bate for the determination of 
several doubtful forms, and especially to the Rev. A. M. 
Norman for his courteous assistance in this respect, and in 
revising the list. Mr. G. S. Brady kindly furnished me with 
the names of the Ostracoda occurring in shell-debris on the 
West Sands and other collections. 
