384 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 14 



spines. The ascopore is of the usual lunate type with a slightly elevated 

 collar. The avicularium is moderate in size, located usually in the lateral 

 zooecial angle and directed laterally; the mandible, with a complete 

 pivot, has a short triangular base, narrows considerably for a short 

 distance, broadens again into a narrow lanceolate form and ends in an 

 acicular point, the under surface grooved nearly to the tip and a pair 

 of small hooks turned downward at its widest part. Length 0.25 to 0.30 

 mm. 



Ovicelled zooecia differ strikingly in appearance due to the extension 

 of the peristome which continues distally across the front of the ooecium 

 and proximally surrounds the ascopore, while on each side is a lappet 

 which bends across to unite with the opposite one and forms a complete 

 bridge on a level with the top of the ovicell; the secondary aperture is 

 thus divided, somewhat unequally into two, the distal one for the ten- 

 tacles, the proximal one for the ascopore. The ovicell is globular, promi- 

 nent, its surface like the frontal and without umbo or ribs, its average 

 width 0.26 mm. 



Type,AHFno. 81. 



Type locality Hancock Station 137-34 Sulphur Bay, Clarion Island, 

 Wof Mexico, 18°9'05"N, 114°45'25''W, 57 fms. Also Stations 147-34 

 and 155-34, Albemarle Island, Galapagos; 650-37, E. of San Francisco 

 Island, Gulf of California, and 298, Agua Verde Bay, Lower California, 

 in the Gulf of California ; 20 to 60 fms. 



Microporella tractabilis Canu and Bassler, 1930 

 Plate 45, fig. 2 



Microporella tractabilis Canu and Bassler, 1930:22. 



The zooecia are of average size, 0.55 to 0.60 mm by 0.40 to 0.50 

 mm, finely granulated, with small tremopores and there is no indication 

 of an umbonate process. The aperture is somewhat more than a semi- 

 circle, 0.07 mm long by 0.10 to 0.12 mm wide, straight on the proximal 

 border, the cardelles more prominent than usual. The peristome is thin, 

 slightly raised and bears 4 to 6 small spines. The ascopore is large, 

 nearly straight on its distal border which has a projecting shelf that 

 leaves a lunate opening; the pore is situated farther from the aperture 

 than is usual in the genus, its border only slightly raised. The avicularia 

 peculiar in arrangement, paired, one on either side, distal to the ascopore 

 and directed straight forward parallel to each other; the mandibles are 

 long and setose. Canu and Bassler state (p. 22) "the mandibles are 



