48 PEOCEEDINGS or THE NATIONAL MUSEUM vol. 72 



very elongated zooecia. Each avicularium is adjacent to three zo- 

 oecia but rarely a zooecium is adjacent to two avicularia. 



Affinities. — Very close to Tremogasterina mucronata Smitt, 1873, 

 in the presence of its frontal mucro, this present species differs in the 

 presence of its concave cribriform area and in the occurrence of five 

 instead of four spines. The figured specimen only has been found. 



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

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



Holotype.—Csit. No. 7601, U.S.N.M. 



TREMOGASTERINA LANCEOLATA, new species 



Plate 13, Figure 9; text Figure 6a 



Description. — The zoarium encrusts nulhpores. The zooecia are 



distinct, separated by a line of interjunctural pores, very elongated, 



elliptical; the frontal is convex, very finely granulated; it bears a 



cribriform concavity perforated by one to five pores. The aperture 



is pyriform, elongated; two small cardelles separate a large anter 



from a small, narrow, concave poster; the peristome is thin, salient, 



ornamented with three large hollow spines. The avicularia are very 



large, much elongated, lanceolated, with two denticles for pivot. 



!#■ J A i. f^<x = 0.17 mm. 



Measurements. — Aperture , 



Ua = 0.12 mm. 



\Lz = 0.80 mm. 



^°°^H2= 0.30-0.50 mm. 



. . , . fZay = 0.60 mm. 

 Aviculariai , ^ „ _ 



[Lav = 0.25 mm. 



Structure. — This is a very fragile species of which minute fragments 



only have been studied. When the frontal calcification is not too 



great, five pores are visible in the cribriform area; there is only one 



of them on the calcified frontals. 



The operculum is very thin, absolutely indistinct in its proximal 



portion, and in consequence directly attached to the ectocyst; it bears 



an internal and complete sclerite characteristic of the genus. 



This species is very well characterized by its large lanceolate 



avicularia. 



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



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



Albatross Station D. 2320, north of Cuba; 23° 10' 



39" N.; 82° 18' 48" W.; 130 fms.; fine coral. 



Holotype.—C&t. No. 7836, U.S.N.M. 



TREMOGASTERINA MALLEOLUS, new species 



Plate 13, Figures 5-8; Plate 33, Figure 8 



Description. — The zoarium is unilamellar and appears to spread 

 over large surfaces on algae. The zooecia are distinct, separated by 



