CRATENA. 25 



but not grooved and not produced into tentaculiform angles. The internal organs are 

 somewhat decomposed, but appear to be as is usual in the Aeolididse. The jaws are 

 thin and yellow, with a single row of distinct denticles, some pointed and some blunt. 

 The uniseriate radula consists of thirty-one reddish-yellow teeth (fig. 27), with seven 

 distinct fairly stout and long denticles on each side of the central cusp. 



The hepatic diverticula are irregular in outline, and the reddish dots appear to be 

 on them and not on the external surface of the cerata. The cerebro-pleural ganglia are 

 roundish, and considerably larger than the pedal ganglia. The olfactory ganglia are 

 round and close together. An auditory organ was not found. The hermaphrodite 

 gland consists of large and small lobes. No armature was discovered on the verge. 

 The animal cannot be safely reconstructed from the fragments preserved, but it 

 certainly looks as if it had had a fringe of small cerata round the dorsal area, and a few 

 much larger ones grouped round the vent. 



10. CUTHONELLA MODESTA. 



ONE small specimen of a uniform greenish yellow, labelled " W.Q., 1, XII., 02., D net, 

 Hut point, 123, Picric acid." As preserved it is only 3' 2mm. long and I'l broad. 

 The cerata are stoutish and rather inflated ; the tallest are less than 1mm. high, the 

 smallest are mere tubercles. They are very deciduous, and most have fallen off, but 

 apparently there were only two longitudinal rows on each side. The pericardium is 

 large ; to the right of it lies the anus, which is latero-dorsal. The genital orifices are 

 just behind the rhinophores. The rhinophores are large, thick and simple, the oral 

 tentacles short and thick. The foot is broad with expanded lateral margins and a thick 

 anterior margin produced into short processes on either side. 



The jaws are white and membranous. The masticatory edge is not even, but can 

 hardly be said to bear denticles. The radula consists of a single row of 27 teeth, 

 yellowish, and of horse-shoe shape. They bear five denticles on each side of the central 

 cusp, which is low and shorter than the lateral denticles, so as to be hardly visible. 



(?) 11. CRATENA SP. 



LABEL, " W.Q., 29 v. 03., No. 4 Hole, 5 fms." The tube sent with this label was said 

 to have contained " four minute Aeolids," but, unfortunately, it was received in a 

 broken condition and its contents were dry. There were found in it only the shrivelled 

 remains of one aeolidiform animal, whitish, 5mm. long and 1 5mm. wide. Nothing 

 could be distinguished externally except the tentacles and two or three longish cerata. 



The jaws are transparent, with a single row of large, distinct, but rather irregular 

 denticles. The radula is uniseriate, and consists of 15 colourless teeth of the narrow 

 horse-shoe shape, with a long, strong central cusp and five clear-cut, longish denticles on 

 each side. 



This animal is very probably a Cratena, but identification is impossible. 



