76 PROCEEDINGS OF THE NATIONAL MUSEUM vol.72 



not seen the internal ectocyst. Our conclusions on the structure of 

 this beautiful species are then very insufficient and we are not able to 

 class it accurately. It is by the simple exterior aspect of the frontal 

 that we introduce it doubtfully and provisionally into the genus 

 Figularia. 



Occurrence. — Albatross Station D. 2167, off Habana, Cuba; 23° 10' 

 40" N.; 82° 20' 30" W.; 201 fms.; coral. 



Eolotype— Cat. No. 7494, U.S.N. M. 



Family HIPPOTHOIDAE Levinsen, 1909 



Genus HIPPOTHOA (Lamouroux, 1821) Hincks, 1880 



HIPPOTHOA EBURNEA Smitt, 1873 



1873. Gemellipora eburnea Smitt, Floridan Bryozoa. Kongl. Svenska Veten- 



skaps-Akademiens Handlingar, vol. 11, no. 4, p. 35, pi. 9, fig. 178 (not 



pi. 7, fig. 152-156). 



T,, ^ A . f^a = 0.06 mm. 



Measurements. — Aperture^, 



^ Ua = 0.04 mm. 



„ . [is = 0.40 mm. 

 /jooeciai 7 n -. ^ n 1 P 



U2 = 0.14-0.16 mm. 



Variations. — The length of the zooecium is quite variable; with 

 the caudal portion it often measures 0.60-0.70 mm., but it may be 

 elongated much more and double this length. 



This is a very fragile species and, although it is not rare, it is dif- 

 ficult to find a well-preserved zoarium for the frontal is often broken. 

 It chooses, moreover, for its development, sheltered places, the inte- 

 rior of dead shells, the inferior face of Cellepores, the base of arbor- 

 escent corals, the folds of nullipores, etc. 



One must not confuse this species with the creeping portions of 

 Pasythea eburnea Smitt, 1872. We can not explain SmJtt's confusion, 

 for this species has neither the same dimensions nor the same aper- 

 tural form. 



Occurrence. — Albatross Station D. 2317, north of Cuba; 24° 25' 

 45" N.; 81° 46' 45" W.; 45 fms.; coral. 

 Albatross Station D. 2362, east of Yucatan; 22° 08' 



30" N.; 86° 53' 30" W.; 25 fms.; coral sand. 

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

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

 coral. 

 Albatross Station D. 2672, Atlantic, east of Georgia; 

 31° 31' 00" N.; 79° 05' 00" W.; 277 fms.; coarse 

 brown sand. 

 Florida, 194 meters (Smitt). 



