of the Fishery Board for Scotland. 



83 



Genus Phyllobothrium, P. J. van Beneden (1850). 



Phylloboihrium thridax, van Beneden. PI. V., fig. 9. 



1850. Phyllobothrium thridax, Les Vers Cestodes, p. 122. 

 PI. V. 



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 records it from Raia clavata captured in the 

 Irish Sea. Olsson has recorded the same Cestode from Raia batis captured 

 in the Oresund, and Lonnberg 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, PI. 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 

 circidaris captured in the Irish Sea. Van Beneden states that it is com- 

 mon in the Smooth Hound, Mustelus vidgaris, and records it also from the 

 Picked Dog-fish, the Grey Skate, and the Thornback, and Malard records 

 it from Trygon vulgaris and one or two of the Plagiostomes already 

 referred to 



Genus Acanthobothrium, P. J. van Beneden (1849). 



Acanthobothrium coronatum (Rudolphi). PI. V., fig. 2. 



1819. Bothriocephalus coronatus, Rud., Entozoorum Synopsis, 

 p. 141. 



1850. Acantliobothrium coronatum, van Ben., op. ext., p. 129, 



PI. VIII. and IX. 

 1906. Acantliobothrium coronatum, Johnston, op. cit, p. 155. 



I obtained this species in specimens of Grey Skate, Raia 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 cancula, 

 the lesser Spotted Dog-fish; Mustelus vulgaris, the Smooth Hound; 

 Squatina angelus, Trygon pastinaca, Torpedo marmorata, Raia batis, 



