404 



Plate XVII. 



Fig. 1 a. Escharella diaphana (Mac Gilliv.). A young 

 colony with the primary zooecium. Pore- 

 chambers are seen on three zooecia. X 40. 



— 1 h. Two zooecia of the same species. Pores are 



seen inside the marginal ridge. X 40. 



— 1 c. The same species. The distal half of a zooe- 



cium, the frontal wall of which has been 

 removed, so that the highly developed vesti- 

 bular arch may be seen and the rods by 

 which it is connected with the lateral walls. 

 X 55. 



— Id. The distal half of a zooecium of the same 



species, seen from the basal surface after 

 removal of the basal wall. The basal wall 

 of the vestibular arch is seen. X 55. 



— 2 a. Escharella abyssicola (Norman). A sagittal 



section through a zooecium with ooecium. 

 The ooecium is surrounded by a kenozooe- 

 cium, the frontal wall of which seems to 

 be united with that of the ooecium. X 40. 



— 2 b. The same species, from the basal surface. 



Three ooecia are present, the surrounding 

 kenozooECia of which are furnished — like 

 tlie zooecia — with pore-chambers. X 17. 



— 3 a. Escharella iinmersa (Flem.) var. The basal 



portion of the endoooecium is surrounded 

 by the cryptocyst of the distal zooecium. 

 X 40. 



— 4 a. Escharoides praestans (Hincks). X 40. 



— 4 b. The same species from the basal surface. 



Pore-chambers. X 23. 



— 5 a. Escharoides saaroglossa n. sp. X 40. 



— 5 b. The same species, from the basal surface. 



The vestibular arch with its thickened 

 margin is seen. X 40. 



— 5 c. The distal end of a zooecium of the same ' 



species. Proximally to the spines the vesti- 

 bular arch is seen. X 55. 



— 5 d. An avicularian mandible of the same spe- 



cies. X 75. 



— 5 e. A distal wall of the same species, witli pore- 



chambers. X 40. 



— 5 f . Three opercula of the same species. The 



smallest is not from the same colony as 

 the two large ones. X 75. 



Fig. 6 a. Exochella longirostris Jullien. X 55. 



— ■ 6 b. A zooecium of the same species, from the 

 basal aspect, after removal of the basal 

 surface. The primary aperture is seen and 

 also the secondary and tertiar3'; further 

 the vestibular arch. X 75. 



— 7 a. Exochella lobata n. sp. X 75. 



— 7 b. The distal end of a zooecium of the same 



species, from the basal aspect, after removal 

 of the basal surface. The vestibular arch 

 is seen in addition to the primary and 

 secondary apertures. X 75. 



— 7 c. An operculum of the same species. X 140. 



— 8 a. Exochella zelanica n. sp. X 75. - 



— 8 b. A zooecium of the same species. Three 



Ijore-chambers are seen. X 75. 



— 8 c. A zooecium of tlie same species, lateral 



view. The strong rostrum proximally to 

 the aperture is seen and also the marginal 

 ridge which is very prominent, running 

 out Into lobes. Inside the ridge pore-canals 

 are seen. X 75. 



— 9 a. Exochella tricuspis (Hincks). X 75. 



— 9 b, The distal end of a young zooecium of the 



same species, whicli shows the primary 

 aperture. Three pore-chambers. X 75. 



— 9 c. The distal end of a zooecium of the same 



species, from the basal aspect, after re- 

 moval of the basal surface. The vestibular 

 arch, the primary aperture and the three 

 coalesced teeth of the secondary aperture 

 are seen. X 75. 



— 9 d. An operculum of the same species. X 140. 



— 10 a. A multiporous rosette-plate of Smiliina 



Pallasiana (Moll.). X 350. 



— 10 b. A schematic longitudinal section through 



a multiporous rosette-plate. To the right 

 is seen the pore-ring. 



— 10 c. A schematic longitudinal section through 



a pore-chamber. To the right the oblique 

 wall on which the rosette-plates are situ- 

 ated. 



