DESCRIPTION OF SPECIES 119 



a specimen of length 3-4 cm. the longitudinal bars have the following arrangement: dorsal line 4(16) 

 2 (16) 2 (22) 2 (24) 2 (17) 2 (13) 3 (8) 1 endostyle. There is, in some specimens, a slight tendency for 

 the longitudinal bars to project at the posterior ends of the branchial folds, as in P. jacatrensis. 



Gonads. I have nothing to add to the existing accounts of the gonads, except to note that in one 

 specimen (St. 1948) the right gonad is Y-shaped, having two branches (Text-fig. 45 G). 



Distribution. Antarctic (McMurdo Bay, Kaiser Wilhelm II Land, Alexander I Land, Graham 

 Land, South Shetlands, Wilkes Land, South Georgia, near Shag Rocks). 



Pyura squamata Hartmeyer (Text-fig. 46) 

 Pyura squamata Hartmeyer, 1909-11, p. 1337 (nomen nudem); 1911, p. 439, pi. 45, fig. 12, pi. 50, figs. 1-5. 

 Occurrence. St. 187: Palmer Archipelago, 259 m. 



External appearance. The single specimen is 1-7 cm. long, i-o cm. broad and 0-5 cm. in height. 

 It is yellow-grey in colour and patterned all over with small, mainly hexagonal plates into which the 

 test is divided (Text-fig. 46 A). 



Text-fig. 46. Pyura squamata Hartmeyer (St. 187): A, part of test; B, oral tentacle; C, dorsal tubercle. 



Internal structure. Owing to the damaged condition of the specimen certain details of structure 

 could not be seen. But the form of the tentacles (Text-fig. 46 B) and dorsal tubercle (Text-fig. 46 C), 

 the arrangement of branchial bars, and the shape of the gonads all conform closely to Hartmeyer's 

 description of the type specimen. The anus is divided into seven rounded lobes; in the type specimen 

 the anus was destroyed. 



Remarks. This species is characterized principally by the polygonal plates of the test, and the 

 presence of only five well-developed branchial folds, with a rudimentary 6th fold. 



In spite of the damaged state of the only specimen in the ' Discovery ' collection I have no hesitation 

 in assigning it to P. squamata. 



Distribution. Antarctic (Kaiser Wilhelm II Land, Charcot Land, Palmer Archipelago). 



Pyura legumen (Lesson) (Text-figs. 47 A, B, C; 48; PI. IV, fig. 6) 



Boltenia legumen Lesson, 1830, p. 149, pi. 53, fig. 1. 

 For synonymy see van Name, 1945, p. 326. 



Occurrence. St. 52: Falkland Islands, 17 m. St. 53: Falkland Islands, 0-2 m. St. 55: Falkland 

 Islands, 10-16 m. St. 56: Falkland Islands, 10-5-10 m. St. 57: Falkland Islands, 15 m. St. WS 71 : 



