NATURAL HISTORY SOCIETY OF GLASGOW. 27 



single one here and there, sometimes of a large size, is seen; but 

 in several situations more favourable to their growth in early life 

 — as in Loch Goil, Loch Long, the Kyles of Bute, and Bulloch bay 

 in Cumbrae, — they are found in small quantities attached to the 

 rocks by the under valve, sometimes by its entire surface, where 

 they attain a great age, as may be supposed from the thickness of 

 the shells. Wliile so far commonly distributed, the quantity is 

 yet small, and the nature of the bottom, and, perhaps, of the 

 currents, such as to prevent their increase to an extent that would 

 repay the trouble of collecting them. Loch Ryan is the only loch 

 in the West of Scotland where they are found in any abundance, 

 and there oyster dredging is regularly prosecuted for the supply 

 of the market. 



Whether they are found on the rocks at low water, we are not 

 in a position to say; but on the dredging ground, which is formed 

 chiefly of small stones and gravel, they almost always occur per- 

 fectly free and isolated. Not unfrequently they are brought up 

 adheri]ig to each other in groups of three or four on some old 

 Buccimim or Fusus, but very rarely are they attached to gravel or 

 stones. They present no marks or scars of any adhesion which 

 might have taken place in early life, and from which they had 

 somehow been subsequently separated. Whether the shifting 

 character of the small stones and gravel prevents the young fry 

 from settling down to adhere, the currents must be such as to 

 prevent them all being swept out of the loch to sea. It does not 

 seem likely that they could voluntarily detach themselves like 

 other byssiferous mollusks. On the gravel of the spit running 

 out to the perch off Inellan we have picked up a few also quite 

 unattached. 



Oyster dredging is carried on from the first of September to the 

 first of May. During the close time, spawning takes place, and 

 the young fry are not disturbed. The chief beds begin about 

 three or four miles down the loch, and extend across its entire 

 area. At special times particular localities are prohibited, and 

 each day the boats change their ground, so that the loch is equally 

 dredged throughout. The oyster fleet consisted of 1 7 boats, each 

 with four men, who were paid by the hundred of oysters. The 

 number of boats varies with the supply dredged. They are also 

 restricted to a size, and being large and heavy, require a main-sail 

 and jib, so that a steady breeze is necessaiy for a successful fishing. 



