358 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 14 



cylindrical branches; zooecia indistinct except at the growing edge; 

 frontal wall very thick with tubular pores; distal part of zooecium 

 raised, with stout oral spines; ovicell globular but soon covered by the 

 distal pleurocyst except for a median cicatrix. 



Gemelliporina monilia new species 

 Plate 41, fig. 13 



Zoarium uniserial, encrusting on the rough surface of a small 

 pebble, sparsely branched dichotomously. Zooecia small, 0.35 to 0.40 

 mm long by 0.25 mm wide, the base sometimes expanded to 0.30 mm; 

 the proximal end only slightly narrowed. The frontal is a pleurocyst 

 with small areolar pores; ventricose and the sides sloping downward 

 to the dorsal side which is more or less expanded for attachment. 

 Proximal to the aperture is a high arcuate umbonate process of varying 

 size, sometimes not wider than the aperture, sometimes forming a high 

 border around the sides of the aperture at a little distance from the 

 peristome. The aperture is elongate, key-hole shaped, almost exactly 

 like that of G. glabra (Smitt) the genotype; 0.13 mm long by 0.08 mm 

 wide, the anter ellipsoid and the poster much smaller, resembling a 

 deep sinus. The resemblance to glabra is further enhanced by the 

 presence of six oral spines. The peristome is low and thin and is not 

 encroached on by the thickening of the frontal. The operculum has the 

 form of the aperture, moderately chitinized, with a narrow sclerite 

 extending forward from the point of attachment somewhat within the 

 border. The spines are peculiar in that there is a regular gradation in 

 size, the proximal one on each side being tall and strong, the next one 

 only about half as large and the third quite diminutive. 



The primary ooecium is globular, hyperstomial, smooth, imperforate 

 and not closed by the operculum; secondarily a thick fold of the 

 frontal of the distal zooecium partly covers it. 



The specimen is very small, with only 12 zooecia, three of which 

 are ovicelled. The ancestrula is similar to the later zooecia except that 

 it is much smaller; it gives off a string of zooecia from each end, one 

 of which shows the base of a branch. 



Type,AHFno. 71. 



Type locality, Hancock Station 270, Angel de la Guardia Island, 

 Gulf of California, 29°29'00"N, 113°27'00"W, 14 fms. 



