226 



BULLETIN 106, .UNITED STATES NATIONAL MUSEUM. 



Affinities. It is not certain that the zoarium was articulated. The only 

 claviform segment (fig. 18) observed contained radicular zooecia at its base; but this 

 might well be considered as the base itself of the zoarium. Nevertheless we have 

 never observed branched segments. 



ople.. 



/occl 



..-ople 



,-ci-ypt 



A 279 



FIG. 60. Anatomy of the subfamily Mleroporidae. 



A. Micropora unicifera Busk, 1SS4. Sketch showing anatomy of polypide, X 270. (After 

 Jullien. 1888.) 



B. Micropora coriacea Esper, 1791. Transverse section through the endozooecial ovicell, 

 X 40. (After Levinsen, 1909.) 



C. Sketch combining frontal (to the left) and basal (to the right) views of Micropora. 

 (After Harmer, 1902.) 



'rii/it, cryptocyst. 



/. intestine. 



mdfi, dilator muscles of the tentacular sheath. 



mg, large retractor muscles of the polypide 



(of the sheath and of the lophophore). 

 mop, opercular occlusor muscles. 

 mp, parietal muscles. 



occl, occlusor muscles of the operculum. 



oe, esophagus. 



ople, opesiule (frontal view). 



ople', opesiule (basal view). 



pli. pharynx. 



/, tentacles (10 in number). 



This fragile species is very close to Smittipora (Vincitlaria) canalifera Hage- 

 now, 1851 of the Maestrichtian. from which it differs in its smaller micrometric 

 measurements (Lz 0. 34 mm and not 0.44 mm.) and in its elliptical instead of 

 subcircular opesium. 



