40 Befiori of the Billiarzia Mission in Egijj^f, 1915. 



Attempts to Infect Animals Experimentally. 

 Three cercariae of bilharzial type were found in four different 

 species of molluscs. The first form met with differed considerably 

 from the other two, more especially in possessing a pair of black 

 pigment spots just anterior to the ventral sucker, and a delicate but 

 well-defined cuticular expansion on each side of the two prongs of 

 the l)ifid tail. This form was found exactly five weeks after the 



Fici. 14.— Marsh, near Kosti village, south-west of Ismailia. 



commencement of our search, and occurred in Planorhis mareoticus 

 collected from the ponds in the Zoological Gardens at Giza. Appa- 

 rently identical cercarise were found later at Giza and Suez in 

 Melania tuherculata, and at Ismailia in Planorhis hoissiji. The 

 second bilharzia cercaria occurred in large numbers in Planorbis. 

 boissyi at El Marg, and was found later in similar canals between 

 Inshas and Bilbeis in the Sharqia province. A very few cercarire, 

 apparently identical with this, were recovered on one occasion only 

 from a Mrkoiia tuherculata in the Zoological Gardens. A third 



