ART. 13 BRYOZOAN FAUNA CANU AND BASSLER 35 



ascopore is large, lunate arranged on the frontal at the bottom of the 

 peristomie. The gonoecia are very broad without peristomie and 

 without avicularia. The ancestrula is a small ordinary zooecium. 

 Measvfremen ts . — 



[Z3 = 0.60-0.70 mm. [ Ap = 0.10-0.12 mm. 



Zooecium | 7^ = 0.4^0.48 mm. Peristomice | ^^=o.i0-0.12 mm. 



Variations. — The zooecia with very long peristomie border only the 

 zoarial margins ; they are observed also on the very small colonies and 

 around the ancestrula. They, therefore, characterize the young cells. 

 On the others the reduction of the length must correspond to a great 

 thickening of the frontal. The width of the zooecia is variable and 

 may measure 0.60 mm. All of our specimens were dead, and we have 

 observed only two gonoecia. 



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



Cotijpes.—C^t. No. 8507, U.S.N.M. 



Family PHYLACTELLIDAE Canu and Bassler, 1917 

 Genus LAGENIPORA Hincks, 1877 



LAGENIPORA VERRUCOSA, new species 



Plate 6, Figure 1 



Description. — The zoarium incrusts dead Cellepores. The zooecia 

 are distinct, separated by a deep furrow, and have the form of a 

 swollen bottle; the frontal is very convex, verrucose, formed by a 

 tremocyst with small pores superposed upon an olocyst. The peri- 

 stomie is oblique, short, smooth at the extremity, partially covered by 

 the tremocyst; the peristome is thick, smooth, orbicular. The aper- 

 ture hidden at the bottom of the peristomie is elongate, elliptic. The 

 ovicell is small, opening into the peristomie above the aperture, finely 

 perforated, marginated by a salient thread. The ancestrula is a 

 small ordinary zooecium. 



Measwrements. — 



[Zs=0.75-0.80 mm. \ha=Q).lQmm. 



Zooeciumj ^^ = 0.50 mm. Apertura j/^=.o.l4 mm. 



Sti^cture. — It is easy to follow on our photograph the development 

 of the ovicell. It develops at the same time as the peristomie elon- 

 gates and the peristome grows definitely above it. It is of endo- 

 cystal nature and inserted between the olocyst and the tremocyst; 

 the frontal is therefore olocystal and the bordering thread the vestige 

 of the tremocyst arrested in its development. This mode of forma- 

 tion and structure appear to be general in the genus. The ancestrula 

 shows no particular character and is surrounded by five zooecia. Its 



