ON THE AFFINITIES OF THE FAMILY OF THE MEDUS/E jt 



Fig. 25. Marginal vesicle from the under surface. 



a. Dilatation of the canal. 

 Fig. 25 a. Marginal vesicle and pedicle very much enlarged. 



Jihhoslo/na mosaica. 



Fig. 26. View of the under surface of the disc, the brachiferous plate being cut away. 



a. Marginal vesicles. 



h. Cut extremity of the suspending pillar of the brachiferois plate, 



t. Central crura. 



d. Lateral crura. 



e. Generative folds. 



f. Connecting membrane. 



Fig. 26 a. Vertical section of the Rhizostoma. 



Fig. 27. Side view of the brachiferous plate detached. 



PL. XXXIX. [Plate 4.] 



Rhizostoma mosaica. 



Fig. 28. Extremity of one of the ultimate ramifications of the arms. 



a. Thick substance of the outer membrane. 



b. The central common canal. 



c. The lateral canals leading to the apertures. 



d. The fringes. 



Fig. 29. Lateral view of one of the apertures much magnified. 



a. Thick outer membrane. 



b. Inner membrane. 

 L. Lateral canal. 



d. Tentacles. 

 Fig. 30. Portion of the testis slightly magnified. 



a. Generative tentacles. 



Fig. 31. Sectional view of testis much magnified, 

 it. Outer membrane. 



b. Inner membrane. 



c. Sperm-sacs. 

 Fig. 31 a. Spermatozoa. 

 Fig. 32. Ovarium. 



u. Outer membrane. 



b. Inner membrane. 



c. Ova. 



Fig. 33. Marginal vesicle, upper surface. 



a. b. Lobes connected by the arched membrane, h. 

 c Cfeca of the canal / 



d. Vesicle on its pedicle. 



e. Cordate depression. 



Fig. 34. Marginal vesicle from below, much magnified. 

 a a. Lobes. 



b. Inferior connecting membrane. 



c. Cieca. 



d. Elevation of the outer meniLrane. 

 t. Muscular fibres. 



