86 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 14 



Retevirgula tubulata (Hastings), 1930 

 Plate 8, fig. 1 



Pyrulella tubulata Hastings, 1930:709. 

 Pyrulella tubulata, Osburn, 1940:14. 

 Retevirgula tubulata, Brown, 1948 :1 10. 



The zoarium is thin and unilaminar, encrusting, but loosely attached 

 by dorsal tubular processes. The zooecia are of moderate size with a 

 considerable range, 0.45 to 0.60 mm long. In some zooecia there is a well 

 developed smooth gymnocyst; in others this is almost wanting. The 

 zooecia are disjunct and connected by tubes, but here there is also much 

 variation and frequently the neighboring zooecia are in contact. Large 

 fenestrae between the zooecia are common, but they are often small or 

 wanting. The avicularia are vicarious on zooeciules which are connected 

 to zooecia or to each other by tubules ; mandible semicircular. The spines 

 are usually 6 on each side, the distal pair directed forward, the following 

 one or two erect and the rest bending over the opesia. 



The ovicell is about 0.18 mm wide, prominent, globular, with an 

 upturned lip, and there is a large rounded fenestra situated somewhat 

 distally on the top. 



Dr. Hastings described the species from the Galapagos Islands and 

 recorded it also from Gorgona, Colombia. Our specimens agree closely 

 with her description. 



Hancock Stations: 59-33, Charles Island, 310-35, Bindloe Island, 

 352-35, Chatham Island and 432, Albemarle Island, Galapagos; 225-34, 

 Gorgona, Colombia; 457-35; Secas Islands, Panama; 132-34, Socorro 

 Island and 223, Clarion Island, west of Mexico; 125-33, Isabel Island, 

 Mexico; 263 and 270, Angel de la Guardia Island, Gulf of California 

 (the most northerly record) ; shallow water to 80 fms. Also Gulf of 

 Panama, Galtsoff collection on pearl oysters. 



^ Retevirgula lata new species 

 Plate 7, fig. 7 

 Zoarium thin, unilaminar, encrusting but very loosely attached, the 

 dorsal surfaces of the zooecia bearing short attachment processes. Zo- 

 oeciules of various sizes are frequent. The zooecia are large, 0.75 to 1.00 

 mm in length by 0.55 to 0.65 mm in breadth ; distinct, their side walls 

 usually in contact, but frequently more or less separated by small fenes- 

 trae, in which case they are connected by short tubular processes. The 

 gymnocyst varies greatly in extent and this accounts almost entirely for 

 the variation in zooecial length ; proximal to the opesia there is frequently 



