SEA-FISHERIES LABORATORY. 321 



Diameter of opening* of ventral sucker : 



0-24 mm. ; 

 Distance apart of centres of suckers : 1'8 mm. ; 

 Diameters of ova : 0*024 x 0'0135 mm. 



The oral sucker is nearly round, but Las two notches 

 on its ventral lip ; the ventral sucker is globular and 

 rather smaller than the oral one. The pharynx is long- 

 and the intestine forks just anteriorly to the ventral 

 sucker, and the rami extend down into the appendix. 

 The latter is about one-third of the total length of the 

 animal, but is retracted to a different degree in some of 

 the specimens. The body when viewed in optical section 

 appears to be provided with small spines, but these are 

 only the edges of fine wrinkles which extend round the 

 body. The skin is quite unarmed. 



The genital aperture lies on the ventral border of the 

 oral sucker, the cirrus pouch lies directly in front of the 

 testes and is provided with a " prostate gland " ; the 

 testes are nearly globular, and are situated end to end 

 at about the middle of the body. The ovary lies some 

 distance behind the testes. The uterus is very 

 voluminous and extends about half-way down into the 

 appendix. 



The vitellaria are very peculiar : there are about 

 half-a-dozen contorted tubes situated immediately round 

 the ovary. The exact number of these structures is, 

 however, difficult to make out because of their tortuous 

 courses. 



Echinostomum imbutiforme, Molin. — Fig. 23 A.B. 



Host : Lahrax lupus, Morecambe Bay, Tuly, 1905. 

 In 1859 Molin* described a Distomum from the 



* Nuovi Myzhelminta raccolti ed. esaminati. Sitzungsb. k. akad 

 Wien, Bd. 37, pp. 818-854. 1859. 



