ART. 14 FOSSIL AND EECENT BKYOZOA CANU AND BASSLER 149 



We have not observed parasites on the inferior face of our lamellar 

 specimens. 



Occurrence. — Fowey Light, 15 miles south of Miami, Fla.; 40 fms. 

 Albatross Station D. 2639, Straits of Florida; 25° 04' 

 50" N.; 80° 15' 10" W.; 56 fms.; coral sand. 

 Geographic distribution. — Pacific: Honolulu, Sandwich Islands, 

 32-64 meters. Indian Ocean: Crozet Island, 340 meters. 

 Plesiotypes.— Cat. Nos. 7530, 7531, U.S.N.M. 



Genus SCHISMOPORA MacGillivray, 1888 



SCHISMOPOEA DICHOTOMA Hincks, 1864 



Plate 22, Figures 7-9; text Figure 34 



1914. CeUepora dichotoma Osburn, Bryozoa of the Tortugas Islands. Pub- 

 lication Carnegie Institution, Washington, No, 182, p. 214. 



1880. CeUepora dichotoma Jelly, A synonymic Catalogue of Marine Bryozoa, 

 p. 51 (Bibliography.) 



i,r ^ A ^ \~ha = Q.\2 mm. 



Measurements. — ^Aperture^ , r. .^r^ /^ -. ,^ 



^ lia = 0.09-0.10 mm. 



Variations. — This is a species well known in the Temperate Zone 



and its presence in the eastern Atlantic has been noted from Norway 



to the Azores Islands. In the Western Atlantic 



it undergoes notable variations. Already at 



Beaufort, N. C, the zooecia are much shorter, less 



oriented, and the colonies have no more the vigor 



... A B 



of the British specim_ens. In the Gulf of Mexico, 



, n 1 p r( • -^^<^- 34.— SCHIZMOPORA 



as our ngures show, as well as those oi femitt, 1873 dichotoma hincks, isei. 

 {C. avicularis, p. 53), the zooecia are short and operculum .^nd man. 

 very erect like those of more typical Cellepores. 

 The colonies are more constantly arborescent and sometimes are 

 lamellose. Finally the apertural dimensions are somewhat divergent. 

 The operculum has a form identical with that Nordgaard figured in 

 1903,^^ but it is smaller and contains two muscular attachments 

 distant from the border. Certainly the specimens from the Gulf of 

 Mexico belong to a variety distinct from the northern type. 



Our specimens from the Pliocene of Panama are free, cylindrical; 

 bifurcated; the zooecia and the avicularia very closely resemble the 

 figure of Smitt, 1873 (0. avicularis); the width of the aperture 

 (0.10 mm.) is almost that indicated by Smitt (0.09 mm.). These 

 specimens, like the recent specimens from the Gulf of Mexico, 

 scarcely resemble CeUepora dichotoma of the northern seas, of which 

 we have very fine specimens; they are far removed also from the 

 variety discovered at Beaufort by Osburn. We give two photographs, 

 for Hincks's synonymy seems premature to us. 



" See Canu and Bassler, 1920 p. 599, fig. 178. 



