of the Hishery Board for Scotland. 
_ Sebastes norvegicus does not appear to be a very rare fish in the waters 
round the more northerly parts of the Scottish coasts, but the examples 
from which the specimens of Vhondracanthus here recorded were obtained 
were captured in the vicinity of Iceland. 
PLATYHELMINTHA. 
TREMATODA. 
Genus Octobothrium, Leuckart (1828). 
Octobothrium Sybille,* sp.n. Pl. IV., fig. 12. 
This is a small species, being only about two and a half millimeters in 
length. Like some others of the same genus, it is flat, elongated, and 
narrow. The anterior extremity is about half the width of the middle 
portion of the body, and is narrowly rounded in front. There are two 
small submarginal suckers on the ventral aspect, one being on each side 
and a little in front of the mouth, which is in the median line. From 
the anterior end the width gradually increases towards the middle, then 
tapers slightly posteriorly. The posterior eud expands and assumes a 
fan-like outline, but with the apex truncated. Round each of the two 
lateral margins of the fan-like expansion are four prominent “‘ suckers.” 
Kach sucker appears to be divided into two subequal portions, as shown 
in the drawing (fig. 12). 
A single specimen of this species of Trematode was obtained on the 
gills of a Trout, Salmo fario, Linn., captured by Dr. H. C. Williamson in 
Loch Tay, Perthshire, in August 1901. 
Genus Distomum. 
Distomum cestoides, Hd. van Beneden. PI. V., fig. 12; Pl. VIL., figs. 3-5. 
1870. Distoma cestoides, P. J. van Ben. Les Poissons des cotes 
de Belgique, p. 17, Pl. IV., fig. 9. 
P. J. van Beneden, in the work referred to above, mentions the occur- 
rence of a large trematode in the esophagus of Raia batis captured on the 
coast of Belgium, which he records under the name of Distoma cestoides. 
A few specimens, comprising adults and young, of what appear to be the 
same species of the Trematoda have been observed in large Raia batis 
brought to the Fish Market at Aberdeen. One of the adult specimens is 
represented by the Photograph Plate VIL, fig. 3. Itmeasures nearly two 
inches in length and between five and six millimeters in diameter. The 
specimen is cylindrical in form, and the ventral sucker is situated near the 
terminal one. One or two of the other specimens were even longer than 
that photographed, the largest measuring about two and three-quarter 
inches in length. | 
It was observed that one or two of the larger specimens were deeply 
pigmented immediately posterior to the ventral sucker; these when 
dissected were found to contain ova in abundance; the ova were of a 
dark chocolate-brown colour, oval in form, and measured about 
1147 x 0806 mm. (PI. V., fig. 12). Besides the mature specimens, 
others varying in size and evidently immature were also observed, the 
a. of which being only six to eight millimeters long (Pl. VII. 
g. 4). 
* Sybilla, Queen of Alexander I. of Scotland and daughter of Henry I. of 
England, is buried in a small island near theeast end of Loch Tay. The Highland 
Tay, by Hugh Maemillan, p. 80. 
