192 
Fart HI. — Ninth Annual Report 
1. Except Loch Creran, the only two lochs in Scotland which can be 
placed under the first head, where any culture has been attempted, or 
where attempts have been made either to keep the ground clean or to 
destroy the enemies of the oyster, are Loch Ryan and West Loch Tarbert. 
Both of these are shallow-water lochs, and are systematically fished by Sir 
William Wallace and Messrs Hay & Co. respectively. Both endeavour 
to remove the starfish and whelks, which are the chief source of annoy- 
ance, and cause the greatest amount of damage to the oysters. The 
starfish, by everting its stomach and enveloping the smaller oysters, 
contrives, after a time, to suck the animal from the shell. In this manner, 
unless the ' Five-lingers' are continually removed from an oyster-bed, they 
will soon make havoc with the stock on the bed. The whelks — chiefly 
Buccinum and Purpura — bore holes through the oyster shell by means of 
the tongue or radula, and extract nutriment from the oyster to the ultimate 
destruction of the life of the animal. The same policy should be fol- 
lowed with the enemies of the oyster as with the enemies of the mussel. 
This consists in digging a ditch on neighbouring land, and burying the 
whole in it. At West Loch Tarbert, Messrs Hay & Co. employ iron rings 
with netting woven across the circle. On these is placed bait, to consume 
which starfish, whelks, and crabs flock. They are lifted daily, and the 
contents emptied into the fishermen's boat. At Looh Ryan the beds are 
cleaned and cleared of the enemies by dredging with ordinary oyster- 
dredges. In this M^ay the enemies as well as the oysters are lifted, the 
oysters either being returned immediately or conveyed to other ground, 
and the enemies retained for destruction. 
The conditions of spatting are so much more favourable to the enemies of 
the oyster, that if the number of these is not continually reduced, they will 
Boon overrun and deplete a valuable oyster scalp. It is satisfactory to know 
that at both places attempts are being made to restore the balance of 
nature in favour of the more valuable oyster. As on land, where weeds 
are rooted up to give the more valuable plants better scope for development, 
so in the water it is as essential to choke off the less useful animal forms 
in favour of the more valuable. 
In Loch Ryan, off Stranraer, it was easy to obtain quantities of fine 
large and healthy oysters. Some of these were as large as 4 inches in 
diameter, and the mantle chambers of many were filled with white spat, 
i.e., with developing eggs of two or more segmentation spheres, while 
fewer contained young that had attained the condition of black spat. 
The age of the large oysters at this place was about four years. In each 
dredgeful, besides living oysters, dead shells of oysters were numerous ; 
and of other molluscs, the numerous occurrence of the false oyster — 
Anomia ephipjnum — was most marked. The way in which the oyster 
and Anomia were mixed with one another was noteworthy, Anomia 
generally being greatly in excess. Sometimes an oyster shell, sometimes 
the shell of Anomia, acted as collector for oysters and Anomice, and it was 
not unusual to find a dozen of both attached to one shell and to one 
another. Anomia is easily distinguishable from the true oyster by the 
mother-of-pearl lustre exhibited by the external surface of its shell, and 
by the hole left in the under valve, or by the calcification of the single 
adductor mUv'^cle which is left in connection with the under valve when 
the valves are separated. Oysters of 1 to 1|- inches were found resting 
on Anomia. The oysters found in Loch Ryan were covered abundantly 
with Serpvkr, frequently with algse, encrusting and otherwise, very fre- 
quently by such encrusting polyzoa as Memhranipora, and less frequeiitly 
by barnacles. The bulk of the oysters obtained ranged from one to three 
years in age. 
While the large oysters which I dredged were obtained high up the loch, 
