16 BULLETIN 16 5, UNITED STATES NATIONAL MUSEUM 



Variations. — The zooecial and opesial variations are great, but the 

 micrometric measurements vary little from those given above, which 

 have been taken on the larger cells. 



The phenomenon of the partial cellular disjunction is quite charac- 

 teristic. Not only is it apparent on the frontal in the interruption 

 of calcification, but it shows still better on the dorsal of the separable 

 lamellae. It has its origin in the independence of the walls of each 

 zooecium, which are never intimately united to those of adjacent 

 zooecia. 



The gemmation is very regular ; the new series arises by the simple 

 division into two of a distal zooecium. 



The regenerated zooecia have a very thick inner mural rim and the 

 new opesium is much smaller than the old one. They are often 

 primoserial. 



The cellular disjunction is not apparent on all the fronds, in which 

 case the general aspect is very artistic and regular. 



Occurrence. — Vincentown limesand : Vincentown (common) and 

 near Blackwoodstown (rare), N.J. 



Plesiotypes.— U.S.N.M. Nos. 73863, 73864. 



Family ALDERINIDAE Canu and Bassler, 1927 

 CRANOSINA, 5 new genus 



The ovicell is endozooecial. A setiform transverse avicularium 

 surmounts each zooecium. The dietellae are extremely conspicuous 

 and about four in the distal half of the lateral wall, their openings 

 to the zooecia often large. 



Genotype. — Cranosina (31 ' enibranipora) coronata Hincks, 1881. 



Range. — Cretaceous (Senonian) to Recent (Equatorial zone). 



The known species of this genus are as follows : 



C. (Membranipora) coronata Hincks, 1881 Recent (Equatorial zone). 



C. (Ellisina) philippinensis Canu and Bassler, 1929 Recent (Philippines). 



C. (Ellisina) lata Canu and Bassler, 1920 Eocene ( Jacksonian). 



C. (Ellisina) brevis Canu and Bassler, 1920 Eocene (Jacksonian). 



C. ( Escharinella) altimuralis Ulrich and Bassler, 1907 



Cretaceous (Vincentown). 

 C. (Membranipora) alumensis Brydone, 1929 Cretaceous (Senonian). 



History. — In 1903 Norman created the genus Ellisina based on 

 characters of secondary or debatable value. He gave a list of species, 

 which deceived Canu and Bassler in 1920, Harmer in 1926, and 

 Voigt in 1930. In 1929 in our Philippine monograph (p. 105), we 

 wrote, after the justified criticism of Harmer : " We could separate 

 a special group having an endozooecial ovicell and a vibraculoid 



6 From Kphvot, crest, in allusion to the place of the avicularia. 



