42 ALLAN HANCOCK ATLANTIC EXPEDITION REPORT 



Family Grepidacanthidae Levinsen 

 Genus MASTIGOPHORA Hincks 1880 



The frontal is a tremocyst, the peristome complete and elevated, the 

 aperture with a sinus, the ovicell small and recumbent, and there is a 

 setiform or palmate avicularium at each side of the peristome. 



Mastigophora pesanseris (Smitt), 1873 



Smitt 1873:43 (Hippothoa pesanseris). Osburn 1914:207 (Escharina) ; 

 1927: 130; 1940: 452. Canu and Bassler 1928: 133. 



This small species is readily distinguished by the presence of a palmate 

 or "goose-foot" avicularium at each side of the aperture, which bears a 

 deep rounded sinus and is completely surrounded by the salient peri- 

 stome. It is widely distributed and appears to be common throughout the 

 West Indian region. Smitt described it from the Tortugas Islands, 

 Florida; Osburn recorded it from the Tortugas, Curasao and Porto 

 Rico and Canu and Bassler listed it from the Straits of Florida and north 

 of Cuba. 



Distribution.— ?>tzt\on At529, 12° 09' 30" N, 70° 31' 00'' at 39 

 fms. 



Family CellepoHdae Busk 1852 



Genus HIPPOPORIDRA Canu and Bassler 1927 



Hippoporidra calcarea (Smitt), 1873 



Smitt 1873:63 (Lepralia edax forma calcarea). Osburn 1914:212 

 (Lepralia). Canu and Bassler 1928: 140. 



This species is usually easily distinguished from Its congener, H. edax 

 (Busk), by the absence of an umbo and by the presence of minute inter- 

 zooecial avicularia. Smitt described it from Florida at 49 to 79 fathoms ; 

 Osburn found it at the Tortugas Islands at 12 fathoms, and Canu and 

 Bassler recorded it from the Gulf of Mexico and the Straits of Florida. 

 They encrust gastropod shells. 



Distribution. — Stations A42-39, At503, At504, At505, and At512. 

 These stations place the locations at Cape la Vela, Colombia ; Margarita, 

 Cubagua, and Aruba Islands at 2 to 23 fms. 



