1869.] and Membranipora Bengalensis. 63 



Fig. 9. Longitudinal section of a portion of an acontium ; 9 a and 9 b, its 



cnidce (p. 44). 

 Fig. 10. A portion of an ovarium, 10 a, shewing the distribution of the 



eggs in the mass ; 10 b, eggs much enlarged ; 10 c, one cnida from 



the ovaria (p. 46). 

 Fig. 11. Appearance of the spermatozoa slightly enlarged. 

 Fig. 12. Male follicle, (see p. 50). 

 Fig. 13. Spermatozoa, very much enlarged. 

 Fig. 14. Eggs surrounded by spermatozoa, (p. 47). 



Plate XII, (p. 55). 



Fig. 1. Natural size, of a portion of the polyzoarium of Membranipora 



Bengalensis ; 1 a, enlarged, with two supposed avicularia on the left 



corner ; 1 b, — If, various stages in the development of one cell (see p. 59) ; 



1 g, a full grown cell with the animal partially protruding, the body 



seen through the transparent cell ; 1 h, the animal taken out (p. 58) ; 



1 i, a statoblast ; 1 7c, internal view of the terminal portion of a tentacle 



(p. 59). 

 Fig. 2. Front view of a few cells, greatly enlarged, also shewing the spines 



attached to the lower lip (p. 57). 

 Fig. 3. Front view of a number of cells of an oval shape ; 3 a, much 



enlarged portion of the upper surface, with two transverse, solid radii. 

 Fig. 4. Much elongated cells which were attached to a stem of a plant. 

 Figs. 5-6. Back-views of two kinds of cells, corresponding to figures 3 and 4. 

 Figs. 7-8. Side-views two cells, shewing the lateral pores by which they 



communicate with the adjoining cells, and also shewing the lower string 



which is well developed in young cells. 



