1 



PLATE XLVI. 



PAGK 



PJieronema giganteum, F. E. S., . . . 250 



Fig. 1. Half of a longitudinally divided specimen, preserved in alcohol ; internal 

 view; x 0-333. 



Fig. 2. Marginal portion, longitudinal section ; natural size. 



Fig. 3. Portion of the outside, the light showing through it ; natural size. 



Fig. 4. Inner surface of gastral cavity ; natural size. 



Fig. 5. Small amphidisc ; x 500. 



Fig. G. Portion of the inner surface of a large passage with large and small auto- 

 canalicular pentact pinuli ; x 200. 



Fig. 7. Section of the wall, with a part of the dermal and canalicular surface ; 

 x60. 



Fig. 8. Oxyhexact with straight echinated rays ; x 200. 



Fig. 9. One of the pores and small autocanalicular pentact pinuli from a large 

 passage ; x 200, 



Fig. 10. Portion of one of the pores within the gastral cavity ; x 25. 



Fig. 11. Portion surrounding the pores in the wall of the gastral cavity; x 200. 



This plate was arranged by Sir Wyvillo Thomson. 



