of the Fishery Board tor Scotland. 83 
Genus Phyllobothrium, P. J. van Beneden (1850). 
Phyllobothrium thridax, van Beneden. PI. V., fig. 9. 
1850. Phyllobothrium thridax, Les Vers Cestodes, p. 122, 
BEV 
1906. Phyllobothrium thridax, Johnston, Report for 1905 of 
the Lancashire Sea Fisheries Laboratory, p. 161. 
This Cestode was obtained in the intestine of the same fish in which 
the Tetrarhynchus minutus was observed, viz., in Squatina angelus, 
captured in the Clyde near Girvan in May 1904. The specimen was 
small and appeared to be immature, though possessing the characters of 
the species, 
Van Benden obtained P. thridax also in the Angel-fish, as well as in 
Raia batis, and Johnston recyrds it from Raia clavata captured in the 
Trish Sea. Olsson has recorded the same Cestode from aia batis captured 
in the Oresund, and Linnberg and Monticelli have also recorded it, but 
it does not appear to be so common as some of the others mentioned here. 
Phyllobothrium lactuca, P. J. van Beneden. PI. V., fig 1. 
1850. Phyllobothrium lactuca, van Ben., op. cit., 120, Pl. IV. 
1906. Phyllobothrium lactuca, Johnston, op. cit., p. 159. 
This was also observed in the Angel-fish from the Clyde mentioned 
above. Johnston records it from Raia batis, Raia clavata, and Raia 
circularts captured in the Irish Sea. Van Beneden states that it is com- 
mon in the Smooth Hound, Mustelus vulgaris, and records it also from the 
Picked Dog-fish, the Grey Skate, and the Thornback, and Malard records 
it from Zrygon vulgaris and one or two of the Plagiostomes already 
referred to 
Genus Acanthobothrium, P. J. van Beneden (1849). 
Acanthobothrium coronatum (Rudolphi). Pl. V., fig. 2. 
1819. Bothriocephalus coronatus, Rud., Entozoorum Synopsis, 
p. 141. 
1850. Acanthobothrium coronatum, van Ben., op. cit., p. 129, 
Pl. VIII. and IX. 
1906. Acanthobothrium coronatum, Johnston, op. cit., p. 155. 
I obtained this species in specimens of Grey Skate, Ruia batis, from the 
Fish Market, Aberdeen, in March 1901. The specimen, of which only the 
head (or scolex) is represented by the drawing (fig 2), measured sixty-five 
millimeters in length. One of the more important characters by which 
A. coronatum is distinguished seems to be the presence of a group of three © 
suckers above each of the four bothria. These accessory groups of suckers 
form a sort of crown on the apex of the scolex, while immediately beneath 
each group two moderately strong bifid hooks may be seen, as indicated 
in the drawing. 
This species is found in the sexually-mature stage in various sharks and 
rays, and is apparently widely distributed. The following European 
fishes are mentioned among the hosts of this Cestode :—Scyllium canc ula, 
the lesser Spotted Dog-fish; Mustelus vulgaris, the Smooth Hound ; 
Squatina angelus, Trygon pastinaca, Torpedo marmorata, Raia batis, 
