ART. 14 FOSSIL AND RECENT BRYOZOA CANU AND BASSIiER 35 



In the genus Flabellaris Waters, 1898, there are frequently internal 

 avicularia. They can not form a constant generic character, for Am- 

 pMhlestrum perminutum Hincks, 1880, contains analagous avicularia. 



This species differs from Callopora curvirostris Hincks, 1880, in the 

 great delicacy of its mural rim and in the larger dimensions of the 

 zooecia with aborted polypide. 



Occurrence.— AWatross Station D. 2387, Gulf of Mexico; 29° 24' 

 N.; 88° 04' W.; 32 fms. 



Eolotype. —Cht. No. 7469, U.S.N.M. 



Genus CAULORAMPHUS Norman, 1903 



CAULORAMPHUS OPERTUS, new species 



Plate 4, Figures 3-8 



Description. — The zoarium encrusts shells. The zooecia are dis- 

 tinct, separated by a deep furrow, at the bottom of which are small 

 inter] unctural pores; the mural rim is salient, very thick, and supports 

 10 pairs of wide thin spines covering the frontal and four large erect 

 distal spines. The pedunculate avicularium is long, thin, and horn 

 shaped. 



,-. u r\ • [^0 = 0.20 mm. 



Medsuremenis . — Opesiau ^ ,_ 



Uo = 0.10 mm. 



„ . 1X0 = 0.40-0.50 mm. 

 z^ooeciai, ^ _ _ _ _^ 



lZs = 0.20-0.25 mm. 



Structure. — The arrangement of the spines is quite unusual and 

 does not resemble that of the spines observed in the other species of 

 the genus. They are flat, almost adjacent, and are inserted in the 

 angle between the dietellae; a very delicate central canalicule runs 

 throughout their length. They are not erect but are recumbent and 

 their ensemble forms a kind of roof above the ectocyst. The four 

 distal spines are large, erect, and articulated at their base. 



The arrangement of the dietellae is not the arrangement studied 

 by Norman and characterizing the genus. The dietellae are here 

 parietal and completely surround the zooecium. 



The inter] unctural pores are visible only on specimens boiled in 

 Javelle water. They are analogous to those which we have observed 

 in HincTcsina and in Callopora. They are covered by the ectocyst. 

 Our photographs give a good idea of this remarkable little species. 



Occurrence. — Albatross Station D. 2405, Gulf of Mexico; 28° 45' 

 00" N.; 85° 02' 00" W.; 30 fms.; gray sand, broken coral. 



Cotypes. —Cs,t. No. 7471, U.S.N.M. 



Genus MEMBRANIPORELLA Smitt, 1873 



1920. Membraniporella Canu and Bassler, North American Early Tertiary 

 Bryozoa. Bull. 106, U. S. National Museum, p. 281. (Description 

 and text figure.) 



