INDIAN NUDIBRANCHIATE MOLLUSCA. 141 



which is yellow, with the extreme apex white : at the inner base of these papillae arise 

 three delicate bipinnate plumes of a white or pale-yellow colour. Foot linear, spread- 

 ing a little at the sides. Length If inch. 



Bornella digitata, Adams & Reeve, in Voy. Samar. p. 67. t. xix. f. 1. 



Rather rare. Two or three specimens were brought home. 



Family PROCTONOTID^, Alder gj Hancock. 



Body depressed. Cloak more or less distinct. Dorsal tentacles non-retractile. Oral 

 tentacles small or wanting. Branchiae fusiform or linear, arranged round the cloak on 

 each side of the back and above the head in front. Anus dorsal or lateral. Mouth with 

 corneous jaws. 



Genus Madrella, nov. gen. 



Body depressed, ovate, with a distinct cloak. Dorsal tentacles with the upper por- 

 tion papillated ; no oral tentacles. Head broad, with a semilunar veil. Branchiae 

 papillose or linear, placed in several rows round the margin of the cloak. Anus lateral. 

 Tongue narrow, with three pectinated plates in each row. 



The anatomy of this genus proves its close relationship to Antiopa. The buccal organ 

 is extremely large and muscular, and the jaws are very large and strong ; but their cut- 

 ting edges are devoid of the denticulations that characterize these organs in that genus. 

 In this respect Madrella agrees with Proctonotus. The narrow tongue, however, is 

 peculiar, that of the other members of the family being generally broad, with numerous 

 smooth spines. In our species it is strap-formed, with fifty-seven or fifty-eight rows of 

 pectinated plates, three in each row ; the central one has eight or nine denticulations on 

 each side, and a large spine in the centre ; the lateral plates have a large spine at the 

 outer margin, and twelve or thirteen smaller ones or denticulations on the inner margin. 

 The oesophagus is short : it leaves the dorsal wall of the buccal organ further forward 

 than usual. There are apparently no salivary glands. The stomach is wide and irre- 

 gularly rounded. The intestine is a widish tube of moderate length ; it passes to the 

 right, and then dips below the ovary, and, bending backwards, ascends a little to ter- 

 minate in a nipple-formed anus, situated about two-thirds down the right side, directly 

 below the overhanging pallial margin. 



The gastro-hepatic system is arranged much in the same manner as it is in Antiopa. 

 A dark brown foUiculated glandular substance extends all round the animal, within the 

 expanded pallial border. This substance, which, in the living state, would probably 

 assume a branched appearance, is connected with the stomach by three wide tubes, two 

 of which, the anterior, pass from the upper wall of the stomach at its junction with the 

 oesophagus, and go, one on each side, to the foUiculated substance in front ; the third 



