JAPANESE NÜDIBRANCHS. 35 



One large specimen, much flattened and twisted but perhaps 

 150 mm. long with cerata about 70 mm. high. Hood very large, 

 measuring about 75 mm. across. Colour transparent yellowish 

 white, with a strong reddish linge in parts. 



On the sides of the hood are scattered small papillae either 

 simple or combined in tufts. On the back these papillae are 

 larger and form arborescent appendages consisting of a stalk and 

 tripinnate branches. These appendages are as much as 10 mm. 

 long but hardly foliaceous. All the cerata have become detached 

 and only eight are preserved, but the marks on the back indicate 

 that there were ten pairs. They are much flattened and distort- 

 ed but as preserved consist of a smooth, thick basal portion with 

 an ample membranous expansion at the top bearing minute tufts. 

 This configuration however may not be natural. A stout diverti- 

 culum of the liver, of a deep red brown colour, penetrates into 

 the basal portion but does not extend to the membranous expan- 

 sion. The diverticulum bears a knob at the top and on its sur- 

 face smaller knobs which hardly amount to branches. 



The edge of the hood is thickly fringed with cirrhi, set in 

 0-10 rows at the sides, although above the mouth the number 

 sinks to two or three rows. Below the mouth the edge of the 

 hood is indented. The rhinophore sheaths are small (5 mm. high) 

 with a tuberculate process (4 mm.) behind. The foot is a broad 

 groove, measuring about 25 mm. across in front. 



Inside the hood are scattered small tubercles and tufts. The 

 lips are raised into a large fleshy prominence. The mouth is a 

 simple slit, leading into a tube studded with papillae near the 

 orifice and with lumps lower down. About 22 mm. below the 

 lips are a pair of small yellow jaws. They are almost membra- 

 nous but thicker at the point of junction. The edge is hardly 

 denticulate but exhibits faint undulations and striations. The first 

 stomach is fairly large and bears a girdle of 24 black triangular 

 plates, of various sizes but not alternating regularly. The -largest 

 are 5 mm. long. Then comes a constriction marked outside by a 

 very distinct row of pouchlike packers, which is interrupted in 

 one place. After this comes a second stomach with no plates 



