1889.] ENTOZOA IN THE BRITISH MUSEUM. 323 



At present I give only a figure of this new species to ensure its 

 recognition. The detailed description, with anatomical remarks, 

 will be given in a forthcoming paper. Tlie lengths of the cysts 

 of this new species are 6-10 millim. 



Didjimozoon serrani is the first species of this genus found in a 

 fish of the family Percidce, the other known species inhabiting fishes 

 of the families Scombridse and Sphyraenidis. 



C E ST o D A. 



7. Gyrocotyle rugosa, Diesing, Syst. Helm. vol. i. p. 480. 



A specimen taken from the intestine of a Callorhijnchus antarc- 

 ticus from Dunedin (New Zealand). This very strange Cestode has 

 hitherto been found only in Mactra edulis. 



8. Bothriocephalusmacrobothrium, sp. n. (Plate XXXIII. 

 figs. 7, 8, 9.) 



Head small, with the terminal cupula flattened ; bothria lateral, 

 small, yjrominent, with thick margin ; neck very short, subcyHndrical ; 

 body flattened. Anterior segments very small, hardly to be dis- 

 tinguished, becoming gradually more distinct towards the end of the 

 body. The last segments not different in form from the preceding, 

 but a little larger. Genital orifices lateral and in the anterior part of 

 the segments. 



Length of the specimens 16-20 centim. 



The specimens were taken from the stomach of a Trachypterus, 

 sp. inc., from Mauritius, presented by L. Bouton, Esq. 



9. Bothriocephalus platycephalus, sp. n. (Plate XXXIII. 

 fig. 10.) 



Head pointed, triangular, pyramidal, anteriorly truncated, without 

 distinct terminal cupula. Bothria large, much flattened, with in- 

 distinct fossette; neck very short, quadrangular; body flattened. 

 Anterior segments small, the succeeding gradually larger ; posterior 

 margin arcuate ; genital orifices lateral. Lengths of specimens 115- 

 190 millim. 



The host of this new species is Beryx decndactyla of Madeira, 

 from which Entozoa have not been previously described. 



10. Bothriocephalus tetrapterus, von Siebold, in Lehrbuch 

 d. vergl. Anat. d. wirb. Thiere, Berlin, 1848, pp. 120, 143, 147, in 

 notes. (Plate XXXIII. fig. D.) ^ 



I complete Siebold's description of this species, which inhabits 

 Phoca vitulina : — Head cordiform. Bothria lateral, enlarged, with 

 margins expanded, so as to resemble four wings. Anterior segments 

 trapezoidal, distinctly canipanulate ; the following rectangular, not 

 campanulate, the later decidedly quadrate. I have uot observed 

 the incomplete transverse division of the segments described by 

 Siebuld. The male and female generative organs are double in 

 each segment, with two distinct genital orifices, very small, situated 





