ART. 13 



BRYOZOAN FAUNA CANU AND BASSLER 



37 



Family CELLEPORIDAE Busk, 1852 

 Genus HOLOPORELLA Waters, 1909 



HOLOPORELLA QUADRISPINOSA, new species 



Plate 6, Figures 4-6 



Description. — The zoarium incriists bivalves, gastropods, celle- 

 pores, and algae. The zooecia, oriented or marginal, are distinct, 

 separated by a deep furrow, elongated, elliptical; the frontal is con- 

 vex, granulated, sometimes decorated with areolar pores and with 

 small elongated avicularium with pivot. The peristome is salient, 

 thin, decorated with four spines; the apertura is semielliptic and 

 placed at the bottom of the peristomie. In front of the aperture 



Figure 8.— Genus Holoporella Waters, 1909. A, B, Opercula, X 85 of H. tridenticulata Busk, 



1881, THE FIRST WITH THE PROXIMAL BORDER AND THE SECOND BEARING TRACES OF THE TENTACULAR 

 SHEATH. C-E, H. QUADRISPINOSA, NEW SPECIES. C, D, TWO OPERCULA, X 85, AND E, MANDIBLE OF 

 AN INTERZOOECIAL AVICULARIUM, X 85 WITH THICK BORDER AND A COLUMNELLA. THE INTERIOR 

 DECORATIONS MARK THE LIMITS OF THE MUSCULAR FIBERS. F, O, H. HEXAGONALIS, NEW SPECIES. 

 OfERCULA, X 85. H-J, n. POROSA, NEW SPECIES. DIFFERENT FORMS OF OPERCULA, X 85 



there is a small triangular avicularium, the beak at the top ; it limits 

 at its base a pseudorimule formed in the peristomice. The cumulate 

 zooecia are irregular, granulated, ornamented sporadically by rare 

 areolar pores or by small, elliptical avicularia. The peristome is 

 nonsalient and bears two spines. The interzooecial avicularia are 

 narrow, little elongated, with pivot. The ovicell is globose, widely 

 opened above the operculum, much granulated as the frontal. 

 Measurements. — 



Apertura 



ha= 0.15 mm. 

 ha— 0.18 mm. 



Oriented zooecia 



Zs= 0.50-0.60 mm. 

 Zs = 0.35-0.40 mm. 



Structure. — ^At first sight this species resembles Schizostoma be- 

 cause of its pseudorimule cut in the peristomice. Close observation 

 shows that this is in reality formed by the projection of the small 



