130 



PEOCEEDIlSrGS OF THE NATIONAL MUSEUM 



VOL. 72 



Genus HIPPALIOSINA Canu. 1918 



HIPPALIOSINA EOSTRIGERA Smitt, 1873 



Text Figure 27 



1873. Escharella rostrigera Smitt, Floridan Bryozoa. Kongl. Svenska Veten- 

 skaps Akademiens, Handlingar, vol. 11, p. 57, pi. 10, figs. 203-205. 



1914. Lepralia rostrigera Osburn, Brj'ozoa of Tortugas Islands. Publica- 

 tion Carnegie Institution of Washington, No. 182, p. 211. (Not 

 Waters, 1885, Jelly, 1889.) 



1923. Hippaliosina rostrigera Canu, and Basslbr, North American Later 

 Tertiary and Quaternary Bryozoa. Bull. 125, U. S. National 

 Museum, p. 167, pi. 17, figs. 15-17. 



, . , f^a = 0.11 mm. 

 Measurements. — Apertura"^,, ^ -„ 



^ lZa = 0,10 mm. 



. , ,. JX2 = 0.44-0.46 mm. 



Zooecia(ordmary)|^^^Q_26mm. 



, . n , . f^a = 0.12 mm. 



Aperture (ovicelled zooecia)|^^^Q ^^ ^^ 



^ • / • 11 ■.JLz = 0.60 mm. 

 Zooecia (ovicelledju ^ on ™^ 

 ^ '^U2 = 0.30 mm. 



Structure. — The opercula of the ordinary zooecia are of extraordi- 

 nary irregularity and their ornamentation is very transparent and 



difficult to observe. The 

 distal margin is thick and 

 there are two lateral bands 

 very close to the border. 

 The mandibles are also very 

 variable. Some are very 

 short and others long and 

 setiform. They are always 

 unguiculate. The frontal 

 seen by transparency shows 

 the large areolar pores and the pleurocystal granules (sketched in 

 black) . 



The natural history of the genus Hippaliosina is still very incom- 

 plete, for the larva and the anatomy are still awaiting description. 

 Biology. — Our specimens encrust Pectens and Nullipores while 

 Osburn's examples grew on corals and shells. This species appears 

 to prefer coral bottoms. It was in reproduction on March 15, 1885. 

 Its longevity is very great, for we have discovered it in the Middle 

 Miocene of Virginia. It has never left the Gulf of Mexico. 



Occurrence.— Albatross Station D. 2319, north of Cuba; 23° 10' 37'' 

 N.; 82° 20' 06" W.; 143 fms.; gray coral. 

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

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

 coral. 

 Florida, 56-69 meters (Smitt) ; Tortugas, 16-24 meters 

 (Osburn) . 

 Plesiotypes. —C&t. No. 7524, U.S.N.M. 



Fig. 27.— HIPPALIOSINA rostrigera Smitt, 1873. A-C. 



DlTFEEENT FORMS OF THE SETIFORM MANDIBLE OF THE 



avicularium. jD, E. Opercula, X 85 



