4 THE FLATWORM AS AN ENEMY OF FLORIDA OYSTERS. 
from New South Wales in 1907.2 His notes regarding the discovery 
of their injurious effect upon oysters are of interest: 
A few years ago I found that this worm was known to a few of the oyster farmers of 
Georges River, who had repeatedly observed it amongst oysters on various leases, and 
that they distinguished it under the name of ‘‘wafer.’’ As this name appears to be 
fairly suitable, I propose for the future to use it in speaking of this worm. Though, 
as I say, the wafer has been known to certain lessees, no definite connection between 
the oyster and this worm has been shown to exist, and no satisfactory evidence has 
been brought forward to show that the latter was to be added to the already long list 
of oyster pests. However, in the light of recent evidence, I think it will be found 
that this is a pest; that it is at times to be seriously reckoned with, and that it will be 
found to be fairly widespread in our oyster-producing waters. : 
At the end of July this year [1907], J. W. Swainson, of Georges River, handed to me 
for determination a number of examples of the wafer, which, he said, was very plen- 
tiful on his leases at that time. No visit was made by me for the purpose of investi- 
gating the matter. During the early part of September Fisheries Inspector Latta 
brought in a specimen of an oyster (from a lease in the Hawkesbury River) which was 
in the last stage of destruction by one of these flatworms, and which contained the 
worm itself. This specimen had been handed to Mr. Latta by J. Izzard, who had 
stated that the worm was very plentiful on his leases at Bar Island and Pelican Island, 
and that apparently it was destroying the oysters. Upon this it was so arranged that 
I made a short visit to the locality in question, for the purpose of obtaining more 
definite information. At Bar Island I found the wafer present in large numbers, and 
some were found actually at work between the valves of the oysters. Large numbers 
of gaping shells of oysters only recently killed were to be seen on all hands, while the 
same was apparent on Pelican Island (which is submerged at high water). In view 
of the very positive evidence obtained at the time, it is only fair to assume that at 
least a part of these—if not all, probably a very large percentage—had succumbed to 
the attacks of the wafer. I must here point out that although the common oyster 
worm (Polydora or Leucodore) was only too abundant on portions of these leases, none 
of the recently dead and gaping shells which I examined showed the least sign of its 
attacks or of the attacks of the common ‘‘ Drill” or ‘‘Borer” (Urosalpinx), although I 
found the latter (previously unrecognized from this locality) to be fairly plentiful. 
It is of interest to mention that at the time of my visit the oysters were all ‘‘opening 
very badly”; that is, they were in poor condition and were likely to remain so until 
the advent of a freshet in the river. é 
OCCURRENCE OF THE TURBELLARIAN IN 1916-17. 
The distribution of this turbellarian in sufficient abundance to 
attract attention from oystermen, during the oyster season, 1916-17, 
co to have been confined to the western coast of Florida, between 
edar Keys on the north and Tampa Bay on the south, a distance of 
about 110 miles. It was stated that the southern limits had probably 
extended, at some of the earlier periods, as far south as Cape Sable, 
be 2 an approximate range of 300 miles. ; 
In the vicinity of Cedar Keys, Port Inglis, and Tampa the greater 
number of the oyster bars, especially in the more saline districts, 
were infested and had suffered to a greater or less extent. The con- 
ditions were so bad that, for a time, the industry appeared to be 
seriously threatened. The loss, as reported, ranged from 10 to 20 
er cent of the stock on some beds to the destruction of one entire 
ar. A planted bed of 35 acres in Tampa Bay was attacked by this 
worm and the mature and young oysters alike were said to have 
been sie wa annihilated. The bed had been planted just two 
years and had given promise of excellent returns. 
a David G. Stead: Preliminary Note on the Wafer (Leptoplana australis), a Species of Dendrocoelous 
Turbellarian W orm, Destructive to Oysters. Department of Fisheries, New South Wales, November, 1907; 
pp. 1-6. (No other references to turbellarians attacking oysters have come to the writer’s attention.) 
