324 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 14 



is low and smooth, without spines; the secondary peristome rises some- 

 what above it in a broad ring which completely encircles the aperture 

 and is decorated with small low tubercles. The avicularium is very 

 minute, situated close beside the aperture, usually just proximal to one 

 of the cardelles, its rostrum fused with the peristome, the chamber small, 

 the mandible pointed and directed more or less laterally > the avicularium 

 is frequently wanting and is always so small that it may readily escape 

 observation. 



The ovicell is large, about 0.40 mm in length and breadth, some- 

 what depressed, covered with a tremocyst like the frontal and closed 

 by the operculum ; the aperture of the fertile zooecium is broader, about 

 0.24 mm. 



The minute asymmetrical avicularium which appears to be riding on 

 the rim of the peristome is the distinguishing character. 



Type, AHF no. 62. 



Type locality, Hancock Station 1316-41, of? Santa Catalina Island, 

 southern California, 33°20'55"N, 118°30'25"W, at 45 fms. Also Alba- 

 tross Station 2945, near Santa Cruz Island, southern California, 34°N, 

 119°29'30"W, at 30 fms. 



Emballotheca altimuralis new species 

 Plate 37, figs. 6-7 



Zoarium multilaminar, encrusting, white to brownish in color. The 

 zooecia are small, 0.40 to 0.45 mm long by 0.30 to 0.40 mm wide in the 

 primary layer; in the secondary layers they are irregularly hexagonal, 

 often as wide as long. In the primary layer the zooecia are distinct with 

 well marked grooves and separating lines or fillets; in the secondary 

 layers the latter become very thick and high, forming enclosing walls 

 on all sides of the zooecia. The frontal is a tremocyst with numerous large 

 pores, slightly inflated and granulated between the pores. The primary 

 aperture is small, 0.12 mm in either dimension, round, with a broadly 

 rounded sinus and small cardelles set far back. The primary peristome 

 is thin and low; the secondary peristome formed by the fusion of the 

 tremocyst is comparatively thick and tuberculate. 



The most characteristic feature, aside from the high separating walls, 

 is the occasional presence of a long slender curved avicularium which is 

 situated at one side of the aperture, directed proximally and curved 

 around the aperture behind the sinus ; the mandible is triangular at the 

 base and acicular toward the tip, yellow in color, and measures as much 

 as 0.20 mm ; the hinge bar is complete. 



