200 
Transactions of the Royal Society of South Africa. 
EXPLANATION OF FIGURES. 
Figs. 1-4 illustrate the development of the egg up to the hatching of the free-swimming 
miracidium emerging from the egg-shell. 
I. = Intestine. 
E.C.T. =External cellular envelope. 
Gg. = Germ-cells and yolk-cells. 
Ex. T. =Excretory tube. 
Op. = Operculum. 
N.S. = Cells of nervous system. 
C. =Ciliated coat. 
S. = Sucker. 
G. x = Developing mass of germ -cells to give rise to redia. 
Fig. 5. A redia of the first generation. 
Fig. 6. An immature redia of the second generation. 
Fig. 7. An immature cerceria just after it has escaped from the redia. 
Fig. 8. A mature free-swimming cerceria, Cerceria frondosa. 
Fig. 9. Mature Paramphistormim calicophorum Fisch. 
S. x = anterior sucker. 
S. 2 =posterior sucker. 
Oe. 2 = oesophagus. 
Vs. = Terminal region of vas deferens 
Ut. = uterus. 
T.j, T. 2 =Testes. 
Ov. = Ovary. 
Vit. D. = Right vitelline duct from lateral vitelline gland. 
Oot. =Ootype. 
L.C. =Laurer's canal. 
G.P. = Genital aperture. 
The figure represents a ventral view with posterior extremity slightly turned up to 
show posterior sucker. 
