ABT, 14 FOSSIL AISTD EECENT BKYOZOA CAN"U AND BASSLEE 147 



Petrdliella is occupied by several parasitic colonies of Smittina and of 

 Gemellipora, the inferior face and interior of the Holoporella contains 

 absolutely nothing. 



The zoarial development is very rapid; one of our colonies com- 

 pletely suppressed a serpula on which the larva was fixed. 



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



30'' N.; 86° 63' 80" W.; 25 fms.; coral sand. 



Albatross Station D. 2363, east of Yucatan; 22° 07' 



30" N.; 87° 06' 00" W.; 21 fms.; white rock coral. 



Albatross Station D. 2365, east of Yucatan; 22° 18' 



00" N.; 87° 04' 00" W.; 24 fms.; white rock coral. 



Cotypes—Csit. Nos. 7528, 7529, U.S.N.M. 



HOLOPORELLA (?) TUBULOSA, new species 



Plate 24, Figures 1-6; text Figure 33a 



Description. — The zoarium creeps over Serpulae and emits free 



cylindrical bifurcated branches, sometimes adjacent. The zooecia 



are distinct, separated by a salient thread, very large, oriented in 



every direction, not erect, elongated, irregular; the frontal is flat, 



formed of a granular tremocyst and of large expanded tremopores. 



The peristomie is thin, salient, tubular. The aperture is oval, the 



point toward the top very little embedded in the peristomie. The 



peristomie is thin, irregular, suborbicular, rarely indented proximally. 



,^ . A ^ [Aa = 0.18-0.20 mm. 



Measurements. — Aperture^, ^,^ ^.« 



^ Ua = 0.15-0.17 mm. 



\Lz= 1.20 mm. 



Zooeciai, „ „_ 



Us = 0.75 mm. 



Structure. — Our micrometric measurements were taken on the most 

 characteristic zooecia, but their form is generally indefinite and their 

 dimensions variable. 



The operculum is transverse, although the aperture is a little elon- 

 gated. Its form is that of Holoporella; the linear attachments may 

 be confused with the lateral borders. 



Affinities. — This is a very divergent type in the genus Holoporella, 

 for the cells are not accumulated. The long smooth peristomie 

 approaches very much Coleopora, but the absence of the band around 

 the operculum does not authorize the classification in this genus. 



The ovicell is not known. A single specimen from each locality 

 has been found. The specimen from Habana was free. 



Occurrence. — Albatross Station D. 2160, off Habana, Cuba; 23° 10' 

 31" N.; 82° 20' 37" W.; 167 fms.; coral. 

 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. 

 Coty pes. —C&t. No. 7532, U.S.N.M. 



