S'UDIES ON THE DIGENETIC TREMATODES. 48] 
shaped. Oral sucker always distinctly larger than ventral 
sucker; diameters ‘035-04 mm. and ‘03-035 mm. respectively. 
Ventral sucker less than a third of the body-length from the 
posterior end. Intestinal diverticula short, wide apart, and 
do not reach the level of the ventral sucker. Genital body 
less than half the diameter of the ventral sucker. Ductus 
ejaculatorius short and direct. ‘Testes not prominent. Uterus 
voluminous, obscuring the testes and extending slightly in 
front of ventral sucker. Ova ‘020-024 by :011—014 mm. 
Habitat, Pelidna alpina, Avgialitis hiaticula, Anthus 
obscurus,| Numenius arquata,! Motacilla flava,! 
Larus ridibudus.! 
Spelotrema simile Jagersk. 
Jigerskidld, “ Levinsenia pygmea lLevinsen, ete.,” in 
5 2 pyg > 
‘Centralbl. f. Bakter., Abth.i, Bd. xxvii (1900), pp. 732-740. 
Length -4—-6 mm. Maximum breadth -2 mm. “ Biscuit- 
shaped.’ Oral sucker slightly smaller than ventral sucker, 
diameter ‘05—66 mm. Intestinal diverticula reach posterior 
border of ventral sucker. Genital body has diameter at least 
two thirds that of the ventral sucker. Ductus ejaculatorius 
long and convoluted. Uterus not usually voluminous, not 
obscuring testes or yolk-glands. Ova pale, measuring °023— 
026 by -011—015 mm. Habitat, Larus argentatus, Larus 
fuscus, Larus ridibundus.! 
Spelotrema excellens, Mihi (PI. 10, fig. 19). 
Wacol) “Annals and Mag. Nat. Hist., (7) xx, (1907), pp. 
248-251. 
Length *7-1'4mm. Maximum breadth 35-50 mm. Club- 
shaped. Oral sucker slightly larger than ventral sucker ; 
diameter -06—085 mm. Intestinal diverticula terminate at 
the level of the centre of the ventral sucker. Genital body 
nearly as large as ventral sucker. Ductus ejaculatorius short 
and straight. Uterus very voluminous, obscuring testes, 
but not extending in front of ventral sucker as a rule. Ova 
1 New hosts 
