DESCRIPTION OF SPECIES 137 



roughly ovoid with the upper surface slightly flattened, and the two short conical siphons situated 

 fairly close together on the flat portion. The sides of the body are also flattened. Short processes of 

 the test are present on the dorsal flattened area, and also along the mid-ventral line. A light coat of 

 sand covers the whole surface of the body. 



Body wall. Both the test and body wall are quite thin. The internal siphons are conical with 

 toothed borders and prominent radial muscles. Radial longitudinal muscles also pass across the sides 

 of the body, and generally are fewer on the left side than on the right. 



Tentacles. There are twelve quite large pinnate tentacles and, alternating with them, about the 

 same number of very small tentacles. 



0.3 cm. 



Text-fig. 59. Molgula sabulosa (Quoy and Gaimard): A, specimen with test removed; B, dorsal tubercle. 



Dorsal tubercle. The dorsal tubercle has a characteristic horizontal S-shaped slit (Text-fig. 59 B) 

 as described by Herdman (1882) and Kott (1952). 



Branchial sac. In the branchial sac there are seven folds on each side, each fold with about six 

 longitudinal bars. There are no bars between the folds. 



Gut. The oesophagus is short and the stomach has a group of short rounded caeca (st.c). The 

 primary intestinal loop is almost closed except at its anterior bend where the limbs are slightly 

 separated. The secondary loop is a flat horizontal semicircle or crescent, with the opening dorsal. 



Gonads. No gonads were found in this specimen. 



Renal sac. The renal sac is gently curved and is not very large. 



Remarks. Kott (1952, 1954) united M. sabulosa with M. pedunculata, but in spite of certain simi- 

 larities the species are distinct, as shown in Table 37. 



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