78 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



INTERNAL PARASITES OF FISHES FROM THE 

 IRISH SEA. 



By Jas Johnstone. 



Contents. 

 I.— LEBOURIA IDONEA, Nicoll. 

 II.— PROSTHECOBOTHRIUM DUJARDINII (van Beneden). 

 III.— THE GENUS ECHENEIBOTHRIUM, van Beneden. 



(1) Lebouria idonea, Nicoll. 



Habitat : Intestine of Callionymus lyra, Morecambo 

 Bay. 



The present species is the type-form of a new genus 

 proposed by Xicoll for the inclusion of a Trematode found 

 by him very regularly, and in large numbers in the 

 intestine of the Cat-fish, Anarrhichas lupus, and less 

 frequently in the stomach. It is certainly rare in Irish 

 Sea fishes, and I have only found one specimen so far in a 

 Common Dragonet caught in the shrimp-trawl in Ulverston 

 Channel, in Morecambe Bay. 



Measurements of the specimen are as follows : 

 Length : 0*87 mm. 

 Breadth : 0*39 mm. 



Transverse diameter of oral sucker: 0'13 mm. 

 ,, ,, ,, ventral sucker: 0'3 mm. 



Nicoll's specimens varied from 1*5 to 2'5 mm. in length 

 and from 0*7 to 10 mm. in breadth, and are therefore 

 considerably larger than the specimen described here. 

 There are also some other differences, but I think it very 

 probable that the species is the same in both cases, my 

 specimen being apparently immature. 



• " Studies on the Digenetic Trematodes," Quart. Journ. Microsc. 

 Science. Vol. LIII. Pt. 3, May, 1909, pp. 441-451 ; PI. 9, fig. 9. 



