MR. T. H. HUXLEY ON THE AFFINITIES OF THE MEDUSA. 
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Fig. 30. Portion of the testis slightly magnified. 
a. Generative tentacles. 
Fig. 31. Sectional view of testis much magnified. 
a. Outer membrane. 
h. Inner membrane, 
c. Sperm-sacs. 
Fig. 31 a. Spermatozoa. 
Fig. 32. Ovarium. 
a. Outer membrane. 
h. Inner membrane. 
c. Ova. 
Fig. 33. Marginal vesicle, upper surface. 
a a. Lobes connected by the arched membrane, h. 
c. Caeca of the canal f. 
d. Vesicle on its pedicle. 
e. Cordate depression. 
Fig. 34. Marginal vesicle from below, much magnified. 
a a. Lobes. 
h. Inferior connecting membrane. 
c. Caeca. 
d. Elevation of the outer membrane. 
e. Muscular fibres. 
Cephea ocellata. 
Fig. 35. An aperture surrounded by its membrane. 
Fig. 36. Portion of the extremity of an arm, with a young interbrachial tentacle {a). 
Fig. 37 . Extremity of one of the large interbrachial tentacles. 
Diphydce. 
Fig. 38. Vertical section of a monogastric Diphyes. 
Fig 39. Attached ovarium. 
a. Natatorial organ. 
b. Ovisac. 
Fig. 39 «. Youngest stage of ovarium. 
a. Simple process of the common cavity. 
h, c. Ovaria further advanced. 
Fig. 40. Prehensile organ. 
a, h. Early stages. 
Fig. 41. Free-swimming ovarium. 
a. Natatorial organ. 
b. Ovisac. 
