The Plathander" (Xenopus laevis). 
355 
animal diet, since a few placed in a large vessel with a mass of algae 
floating on the water, made no appreciable growth during a period of 
about 2f months and finally died before completing their metamorphoses. 
Fig. 9. — Diagrammatic representation of olfactory organ. E external opening ; 
M and MI = openings into mouth. AC = anterior chamber ; PC = posterior chamber ; 
JO = Jacobsohn's organ. 
They had sufficient plant food, for the water must have swarmed with 
algal spores, and they also passed large quantities of faeces — yet they 
remained approximately the same size for over two months and then died. 
