PLATE VI. 



Fig. 49.— Clytia compressa. u, b, c. Types of hydrotheeae. d. Medusa 

 about to leave gonotheca. Immature gonophore near base of 

 latter, x GO. 



Fig. 50. — Calycella syringa. Hydrotheca; gonothecae, each with a single 

 ovum. 



Fig. 51. — Sertularella dentifera. Portion of stem, with two hydrotheeae. 

 x 30. 



Fig. 52. — Same species. Portion of stem, with bases of two branches aris- 

 ing from hydrotheeae. One hydrotheea slightly ruptured, x 27. 



Fig. 53. — Sertularella fusiformis. Portion of stem, x 30. 



Fig. 54. — Same species, a. Female gonotheca. x 30. 6. Female gonotheca 

 with acroeyst ; ova within gonotheca. x 30. 



Fig. 55. — Sertularella halecina. Hydrotheeae. x 30. 



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