BY H. LEIGHTON KESTfiVEN. 293 



The 671(1 ostyle extends from just dorsal to the oesophageal 

 aperture, round the sac without undulation to near the circum- 

 oesophageal bands, where it presents a deep double loop (PL xxvii., 

 fig.5). The circumcesophageal bands have an even curve without 

 undulations. 



The dorsal lamina is a plain undulating membrane, devoid of 

 teeth and ribs. 



The dorsal tubercle (PI. xxv., fig. 3) is oval in outline, the longer 

 axis being transverse. The aperture is curved so as to include a 

 somewhat cordate area. The subneural gland is a pyriform body 

 lying beneath the nerve. 



The tentacles are numerous (PI. xxv., fig. 3), simple filiform 

 processes. Two grades of size are distinguishable; the larger are 

 about twenty in number, those of smaller size about twice as 

 numerous. Their arrangement is quite irregular, and intermediate 

 sizes are present. 



The genital gland is in the form of a large number of small 

 lobes attached to the mantle on the right side (PL xxvii., fig.l). 



The alimentary canal is divided into regions clearly recog- 

 nisable from changes in colour or size, The situation of the 

 various parts is shown in outline by figure 2, Plate xxvii. The 

 oesophagus is a short slender tube, very delicate and of a dull 

 grey colour; its lumen is triradiate in cross-section. The stomach 

 (PL xxv., fig. 2) is oval in shape, j^ellow in colour, and bears 

 numerous oblique folds, which extend from a smooth area, along 

 the centre of the left side, backwards and to the right side. 

 The intestine is yellow in colour; and the rectum, which commences 

 on the intestinal loop, is dark green. The intestinal loop is neither 

 wide nor narrow, but intermediate. 



Hah. — Hobart Harbour; 5 fathoms (A. Morton). 



D. grega7'ia is apparently a common form ; there are upwards 

 of thirty specimens in the collection; they were attached by the 

 posterior end; clumps of three or four are common, but there is 

 no tendency to fusion of the tests. 



Types to be presented to the Australian Museum. 



Dendrodoa gregaria is apparently very like Styela radicosa 

 Herdman, from which it differs in having no root-like processes 



