NOTES ON SOME BRITISH NUDIBKANCHS. 355 



which are set five processes on the left side and four on the right. The 

 processes in the first pair are opposite one another. Then they gradu- 

 ally become alternate. They Ijear lol)CS with a rather irregular outline, 

 so that the whole process looks like a short, thick hranchial plume. 

 The first pair have eight lobes, four on each side, and are folded along 

 the median line, the concave surface being turned outwards. The 

 second, third, and fourth pairs are similarly folded, but bear only seven 

 loljes, three on each side and one terminal. The fifth process (found on 

 the left side only) has five lobes and is irregular in shape. The genital 

 orifices are close to one another, on the flank of the body, l)etween the 

 rhinophores and the first process. The vent is between the first and 

 second processes, close to the dorsal margin. 



The nervous system is yellowish. The ganglia are hard to separate, 

 but as seen from above appear to be as described by Trinchese. The 

 cerebro-pleural ganglia are large and triangular, showing no sign of 

 division. The pedal ganglia, which are smaller, lie at their side on 

 a lower level. The buccal ganglia are large. The eyes are large and of 

 an intense bluish black. 



The jaws bear a row of distinct but irregularly sha})ed denticles on 

 the masticatory process. Higher up on the jaw itself there seem to be 

 numerous projections near the edge. The radula resembles that of 

 Galvina, and consists of thirty-one rows of three teeth each. The 

 median teeth (PI. xi., Fig. 10. a.) are very strong and distinct, with 

 four well-developed denticles on each side of a large raised median 

 cusp. The laterals (Fig. 10. b.) are very thin and hard to see, but are 

 much as in Galvina, broad, but with a sharjjly pointed summit. 



The animals being small and indifferently preserved, it was difficult 

 to make out the digestive system by ordinary dissection, and the follow- 

 ing details are derived almost entirely from the specimen which was 

 sectioned, A fairly long resophagus (PI. xii., Fig. 11. a.) leads from the 

 buccal mass to the stomach and gives rise about midway to a curved 

 diverticulum (Fig. 11. b.). The stomach (Fig. 11. c.) is roundish and 

 not very large. Yxoiw the top of it rises the intestine (Fig. 11. d.), 

 which sends out a tube to the anal papilla (Fig. 11. e.) on the riglit. 

 The anterior lower part of tiie stomach is prolonged into two diverticula 

 (Fig. 11. f.), wliich supply the first pair of cerata and then run straight 

 forward, terminating in the anterior part of the foot. 1'he termination is 

 trifid. Posteriorly the stomach gives rise to a long and fairly wide tul.ie 

 (Fig. 11. i.), which extends to the hinder part of the body and sends oft' 

 branches (Fig. 11. g.) to the cerata. These branches aie at first simi)le, 

 but before they enter the cerata they divide into as many ramifications 

 (Fig. 11. h.) as there are lobes to supply. These secondary ramifications 

 arise at different levels. At their termination ihey open externally by 



