J^OETH AMERICAN EARLY TERTIARY BRYOZOA. 



239 



a more or le-> widened cone and always with the apex below. It maintains its 

 normal position by the aid of long articulated filaments called vibranila, which are 

 thus organs for the maintenance of stability. 



: 



: 



ai 



. . 



r7fq.!rj 



rH*Jy 



Dx25 



I x60 



B x25 



Ex25 Gx25 



FIG. 64. Subfamily Luuulariidne Levinsen, 1909. 



A-C. Lunularia capulus Busk, 1SS4. A. Zoarium, natural size. B, C. Outer (celluliferoust 

 and inner faces of the zoarium, X 25. (After Busk. 1884.) 



D-F. Lunularia patelliformis Maplestone, 1903. D. Inner face, X 25. E, F. Vibracular 

 cavity and vibraculum. X 25. (After Maplestone, 3903.) 



G, H. Lunularia rcpandus Maplestone. 1903. Vibracular cavity and vibraculum, X 25. 

 (After Maplestone, 1903.) 



I. Internal cast of Luntitiiriu- liar/encnoi Bosq, 1851. (After Beissel, 1865.) 



J. Vertical section of Luinilnria, traversing an ovicelled zooecium. or, ovicell; s. septula : 

 ;octi; zoarium; cp, proximal zooecium. 



K. Vertical fracture of Luiiulurin- tintinalnila, new species, X 10. showing that the zoarium 

 is composed of plurilamellar segments commencing at the center or at a bifurcation. 



The choice of a substratum by the larvae is instinctive but not infallible. 

 Often they affix themselves on very heavy objects on which, nevertheless, the zoa- 

 I'ium developes. (Reptolunulites of D'Orbigny.) 



