ELIOT : NUDIBEANCnS OF NEW ZEALAND. 



347 



DoRiDopsis MAMMOSA, Abraham. 

 Boridopsis mammosa, Abraham : Proc. Zool. Soc, p. 266, pi. xxix, 

 figs. 20-21, 1877. 



Three specimens marked by Mr. Suter, " Doridopsis mammosa, 

 Abraham, Hauraki Gulf." The largest is 46 mm. long, 26 broad, 

 and 14 high. They are all soft, smooth, and flabby, pale yellow with 

 black markings. Traces of brighter colour seem to indicate that the 

 animal is really bright lemon-yellow when alive. 



The dorsal surface bears soft tubercles, both large and small. As 

 preserved, most of them are flattened, but the normal arrangement 

 seems to be that there are 8 tubercles about 6 mm. high, one between 

 the rhinophores, one behind the branchiae, and two rows of three each 

 on either side between the rhinophores and branchiae. These larger 

 tubercles are surrounded by rings of smaller ones, and there are 2-3 

 lines of smaller ones near the mantle-edge. The back also bears three 

 rows of lozenge-shaped or irregularly polygonal figures, boldly outlined 

 in black and contrasting with the yellow surface. The space inside 

 the black outline is yellow like the rest of the back, and there is a 

 spot in the centre. There are 3-4 of these figures in the centre of 

 the back between the two lines of large tubercles and 5 on the outer 

 side of each line near the mantle-edge. The last figures are behind 

 the branchial pocket and imperfectly developed. 



The branchial pocket is shallow, with a few black spots on the floor. 

 Its edge is distorted in all the specimens, but seems to have had six 

 lobes, marked by tubercles. The branchiae are 6, tripinnate, yellow, 

 but the rhachides of the extreme ramifications are black. The 

 rhinophorial sheaths are thin, about 1-5 mm. high, not divided or 

 lobed. The rhinophores are rather large, reflexed, and bear about 

 30 deep perfoliations. The mantle-edge is fairly ample. The foot 

 has ample lateral margins, is pointed in front and not grooved. Over 

 the mouth are two rather broad flat tentacles. 



The intestines are mostly yellow. The blood-gland is very large 

 and yellowish. It lies as preserved not over the central nervous 

 system but on the right, towards the genitalia. The interior of the 

 buccal chamber is bluish-black. Out of the buccal cone issues a thin 

 tube with muscular walls about 4 mm. long and 1 mm. broad. This 

 tube passes into a sausage-shaped dilatation with thinner walls, about 

 6 mm. long and 35 broad, which is bent so as to form a circular loop 

 with the anterior and posterior ends close together. This dilatation is 

 followed by a constriction and a longish tube about 20 mm. long, and 

 of irregular diameter (about 3 mm.) on an average, which dilates again 

 and then enters the liver. The walls of this longish tube are very 

 thin, and in places reticulate with large irregular meshes, like those 

 shown in Hancock's figure of Doridopsis. 



No salivary glands of the usual type were found, but under the 

 anterior part" of the buccal tube lies a large many-lobed yellow 

 gland. It has five principal divisions, but it enters the buccal tube 

 by a single duct. 



The central nervous system forms a complete ring surrounding 

 the end of the thin part of the buccal tube. The ganglia form 



