uiT. 13 BBYOZOAN FAUNA CANU AND BASSLER 17 



true that the Miocene species is still represented in the recent seas by 

 specimens with a tremocystal frontal. Our genus Stephano sella has 

 no further reason for existence and should be suppressed. It might 

 be preserved as an artificial subgenus for the group of species orna- 

 mented with an ovicellarian area. 



Biology. — All of our specimens were living and generally ovicelled. 

 They incrust the fragments of shells in two or many superposed 

 lamellae. The formation of the superior lamellae is occasioned by 

 the development of adventitious colonies arising from larvae affixed 

 to the colony itself. These small, new, orbicular colonies suppress 

 the ancient ones. The vitality of this species is such that the colony 

 is sometimes 5 square centimeters in extent and sometimes entirely 

 incloses the shells and debris. Here are, then, two extremely rare 

 anomalies in the bryozoa. Usually a colony drives the larva far 

 away. Generally also a single side of the shell is incrusted. How- 

 ever, if the latter is fixed to floating algae, we can conceive its com- 

 plete envelopment, but then such colonies do not have any bathy- 

 metric significance. In 1925 (p. 30) we have shown that the bathy- 

 metric data of this species should be revised. 



Our specimens were in reproduction April 7-9, 1888. Those col- 

 lected by the Vanneau on the shores of Morocco were in reproduction 

 July 26, 1923. 



Occurrence. — Galapagos Islands, D. 2813 and D. 2815. 



Plesioti/pes.—Ca,i. Nos. 8485, 8486 U.S.N.M. 



Genus DAKARIA Jullien, 1903 



DAKARIA SERTATA, new species 



Plate 2, Figures 3-6 



De'scription. — The zoarium incrusts Lithothamnion and Cellepores. 

 The zooecia are distinct, separated by a deep furrow, elongated and 

 elliptical. The frontal is very convex and formed by a granular 

 tremocyst with small pores. The apertura is large, suborbicular with 

 a broad proximal, shallow sinus; the peristome is salient, thin dis- 

 tally, very much enlarged and festooned in its proximal part. The 

 ovicell is large, buried in the distal zooecium, very globular, and of 

 the same nature as the frontal, closed by the operculum with a 

 marginated orifice. 



Measurements. — 



fAfl5= 0.14-0.16 mm. [Lz^Q.m mm. 



Aperturaj ?^=o.l6 mm. Zooeciumj ?^==o.30-0.40 mm. 



A-fjinities. — The genus Daharia is still poorly known. It was 

 formed by Jullien in 1903 for the species in which the young orifice 

 61589—29^ 2 



