iiC) Da. F. G. OAWSTON 



In various parts «>i Soiitli Africa sheep are heavily 

 infested with the liver-lluke parasite. I have in iny 

 possession some from Pretoria and Durban, where I have 

 seen the liver of oxen as well as sheep swarming with 

 these leaf-like parasites. Several of the cercariae ihat I 

 have obtained from Lhnnaea natalensis are similar to 

 what ha?s been described as the larval stage of Fasciola 

 lu'imtien; another, (\ pii/iiientosa, develops into Fasciola 

 (jHjantiva. 



I found that 30 per cent, of Planorhis pfeifferi at the 

 Toll Gate brickfields at Durban were infested witli rediae 

 containing a parasite resembling the larval stage of the 

 Lnng-fluke. I have collected snails infested with the 

 same parasite from other parts of the country. 



Amphistom.es are common in cattle and sheep in various 

 parts of the Union. The larval stage of these parasites 

 has not previously been reported in South Africa. How- 

 ever, 1 found 01) out of (»(!() Isidora schakoi at Potchef- 

 stroom infested with AmpJiistoiNa during the months of 

 October to January 11)17 to 1918. The life-cycle of this 

 Amphistome is at })resent unknown; but the pools from 

 which it was isolated swarm with crabs, an interesting 

 variety splitting off from the well known genus 

 PoiarnonauteS: 



Dr. Henry B. Ward, the Editor of "The Journal of 

 Parasitology," has kindly had drawn and described for 

 me the two parasites I have isolated from Isidora schak'n 

 at Potchefstroom. This genus of snail is notoriously 

 polymorpheus and the species very variable; but Mr. 

 Henry C. Burnup has no hesitation in identifying the 

 specimens T sent him from Potchefstroom as Isidnrn, 

 schalxoi, foi' they agree very well with Jickeli's descrip- 

 tion and figures of schal:oi. 



A. — Study of slides labelled Ccrcaria gladii. 



Schistos(^me lai-va. P,0(ly 250 m. long, 73 m. wide; 



Tail 200 m. + 3^0 m. = r,70 m. 



