352 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 14 



shallow secondary sinus. A suboral or labial avicularium is situated 

 transversely above the aperture, a little to one side, the long-triangular 

 mandible directed laterally; no other avicularia have been observed. 

 Multilaminate colonies are nodular and the zooecia oriented in every 

 direction. 



The ovicell is hyperstomial, prominent vv^hen young but becoming 

 more or less embedded, inperforate ; a striking feature is the large rima 

 or fissure which extends nearly to the distal end of the ovicell and 

 apparently never becomes closed. 



The small size and especially the widely cleft ovicell distinguish 

 the species from any of its congeners. 



Type, AHF no. 70. 



Type locality, Hancock Station 155-34, Albemarle Island, Gala- 

 pagos, 0°16'45''S, 91°22'52"W, 50 to 60 fms. Also at Station 170-34, 

 Stephens Bay, Chatham Island, Galapagos, 32 fms; 210-34, Santa 

 Elena Bay, Ecuador, near shore; and collected by Capt. Fred E. Lewis 

 at Acapulco, Mexico, 15 fms. 



Genus AIMULOSIA Jullien, 1888 



The frontal is a thick porcellanous pleurocyst with small areolar 

 pores. The aperture is somewhat bell-shaped, widest at the proximal 

 end ; the poster extends the full width back of the cardelles, its border 

 gently arcuate. The ovicell is hyperstomial, imperforate, not closed by 

 the operculum, the orifice large, not much embedded. Avicularia, typi- 

 cally median and suboral, but sometimes wanting in this position ; lateral- 

 oral and frontal avicularia also often present. Oral spines and dietellae 

 present. Genotype, Aimulosia australis Jullien, 1888:59. 



Aimulosia uvulifera (Osburn), 1914 

 Plate 45, figs. 16-17 



Lepralia uvulifera, Osburn, 1914:210; 1940:427. 

 Aimulosia uvulifera, Osborn, 1947:35. 



Zoarium encrusting, forming small white areas on shell fragments 

 and corallines. The zooecia are small, about 0.25 to 30 mm long by 

 0.20 mm wide, distinct only when young; the frontal a thick porcel- 

 lanous pleurocyst, highly arched and bearing a few areolar pores which 

 are difficult to observe except in calcined specimens. The frontal rises 

 into a high broad umbo which overhangs the aperture and often is 

 trifid at the tip ; frequently there is a much smaller pointed erect process 

 on either side of the aperture, proximal to the oral spines. The aperture 



