PLATE 44 

 Figs. 52 and 53, Eudistoma psammion. 



Fig. 52. Zooid much enlarged, viewed from dorsal side. 



Fig. 53. Branchial sac showing elongated atrial siphon. 

 Figs. 54-56, Trididemnum della vallei. 



Fig. 54. Zooid much enlarged, viewed from right side. 



Fig. 55. Branchial tentacles. 



Fig. 56. Spicule. 



Figs. 57-39, JJidemnum carnulentum. 



Fig. 57. Zooid much enlarged, viewed from left side. 



Fig. 58. Branchial tentacles. 



Fig. 59. Spicule. 



Fig. 60. Didemnnm canndeiitum, var. lacteolum. Spicule. 



[506] 



