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BULLETIN 100, UNITED STATES NATIONAL MUSEUM 



Fig. 90. — Genus Bicellartella Levinsen, 1909 



A-F. Bicellariella ciliata Linnaeus, 1758. A. Zoarium, X13. B. Fragment 

 showing the zooecia with their freely movable avicularia, X33.5. Each zooecium 

 consists of three sections separated by constrictions, of which the middle one is 

 elongated cylindrical, while the distal is obliquely funnel shaped. C. Ovicelled 

 zooecia. The ovicell (ov) is old and leaves after its decay a cicatrix, cov. Proxi- 

 mally to this the forked distal wall is seen, X40. D. Posterior face of the zooe- 

 cia, X335. The basal edge of the distal wall is unequally asymmetrically angu- 

 lar; the radical fibers are issued from the basal side of the zooecium. E. An 

 avicularium, profile view, X 106. F. An avicularium, front view, X 106. (A-F. 

 After Levinsen, 1894.) 



Fig. 91. — Genus Bicellarina Levinsen, 1909 



A-E. Bicellarina alderi Busk, 1859. A. Usual form. Distal wall with small 

 uniporous septulae; free avicularia; zooecia widening from a narrow cylindrical 

 proximal part into an obliquely funnel-shaped extremity; radical fibers issue from 

 the lateral margins of the zooecia. B. Zooecia with ovicell and a double spine. 

 C. Dorsal surface of branch. D. Natural size of zoarium. E. Avicularium. 

 (After Hincks, 1880.) 



