296 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



as natural a condition as possible, or to make general 

 stained preparations of the proglottides. Before pre- 

 serving it is, however, desirable to rinse the animal very 

 gently in fresh water in order to get rid of the mucus and 

 chyle with which it is surrounded. In the case of many 

 species the strobila generally comes to pieces on being 

 preserved and if the whole organism is to be studied it is 

 necessary to preserve such worms, each in a separate tube. 



I. CESTODA. 



BOTHRIOCEPHALID^E. 



Bothriocephalus ( = Dibothrium) punctatus, Budolphi — 



Fig. 11. 



Hosts : Rhombus mcuximus and R. laevis ; at all 

 stations. 



Every turbot and brill examined has so far proved 

 to be the host of one or more of this cestode. Generally 

 the brill harbours only two or three worms, but in the 

 case of the turbot the number is much greater. One 

 turbot 30^ inches in length, caught in Luce Bay in 

 October, 1905, was greatly infested, and I counted over 

 60 Dibothria in the gut exclusive of several which had 

 become detached. All were attached to the walls of the 

 pyloric caeca. 



Two distinct varieties of Dibothrium punctatus are to 

 be noticed (see fig. 11, A and B), and it is hard to resist 

 the impression that we are dealing here with two distinct 

 species. The general morphology of the scolex and 

 proglottides is, however, so similar in both cases that it 

 is probable that we have to deal with varieties only, or 

 at most physiological species, the difference being due 

 to the different habitat. The differences between the two 

 cestodes are (l).tke length and thickness of the head and 



