128 



DISCOVERY REPORTS 



20/i 



Text-fig. 53. Bathypera splendens Michaelsen (St. 181): A, spicule from test; B, dorsal tubercle. 



Family MOLGULIDAE Lacaze-Duthiers, 1877 

 Genus Molgula Forbes & Hartley, 1848 

 Molgula pedunculata Herdman (Text-fig. 54; PI. V, fig. 4) 



Molgula pedunculata Herdman, 1881, p. 234. 

 For synonymy see van Name (1945). 



Occurrence. St. 27: S. Georgia, nom. St. 39: S. Georgia, 179-235111. St. 42: S. Georgia, 

 120-204 m. St. 45: S. Georgia, 238-270111. St. 123: S. Georgia, 230-250111. St. 140: S. Georgia, 

 122-136 m. St. 144: S. Georgia, 155-178 m. St. 160: Shag Rocks, 177 m. St. 190: Palmer Archi- 

 pelago, 93-126 m. St. 599: Graham Land, 203 m. St. WS27: S. Georgia, 107 m. St. MS 68: 

 S. Georgia, 220-247 m - 



External appearance. The largest of the many specimens in the collection is 2-6 cm. long. Almost 

 all of them show some degree of the development of tag-like processes or short hairs on the test. The 

 body is longer than wide, and is generally ovoid or somewhat rectangular, with the siphons sym- 

 metrically placed on the upper border. In some specimens, more often the small ones, the lower part 

 of the body is produced into a narrow stalk, which is occasionally almost as long as the body, but is 

 generally much shorter. 



Internal structure. The variation in the internal structure of the ' Discovery ' specimens will be 

 discussed in relation to Arnback's (1938) account of her species M. angulata, to which, in her prelimi- 

 nary notes, she assigned a number of specimens in the 'Discovery' collection. Table 35 gives the 

 main characters of M. angulata, and of the ' Discovery ' specimens which I identify as M. pedunculata. 



Table 35 



Tentacles 

 Dorsal tubercle 



Branchial sac 

 Gut 



M. angulata 



At least 20 ; the largest bipinnate 

 Transversely elongated; horns inturned; 

 faces back left 



7 folds ; about 1 1 bars per fold ; i or 2 

 bars between folds 

 Sharp bend in intestine 



M. pedunculata ('Discovery' specimens) 



Usually 12-16; the largest tri-pinnate 

 Sometimes transversely, sometimes longitudinally 



elongated ; horns usually inrolled ; usually faces back 



left (see Text-fig. 54 A) 

 7 folds; 6-13 bars per fold; 1-4 bars between folds 



Intestine variously curved, sometimes with sharp bend 

 (see Text-fig. 54 B) 



