Murdoch. — On Paryphanta busbyi. 259 



less than 2 mm. from the edge. On the underside of the 

 mantle is the usual prominent lappet which conceals the 

 respiratory and anal pores, and in addition to this is a long 

 narrow fold on the left side. 



The buccal mass (fig. 1) is enormous in size and muscular 

 development. Its posterior end is curved down and forward, 

 and a powerful ventral muscle firmly binds it to the more 

 anterior cylindrical portion. The retractor muscle (r. m.) en- 

 velopes the posterior end, and from the anterior portion of the 

 mass proceed a number of ventro-lateral muscles (ant. r.m.), 

 which unite with the immediately adjoining body-walls. The 

 oesophagus (as.) enters the buccal cavity dorsally in the 

 anterior fourth. The salivary glands (s. g.) are situate upon 

 the posterior half of the buccal mass ; they are fused together 

 in the median line and partly envelope the oesophagus. From 

 the anterior end of each gland proceeds a small salivary duct 

 (s. d.), which enters the buccal cavity a little below the oesopha- 

 geal opening. The stomach (st.) forms a simple elongated 

 sac, and the tract of the intestine does not appear to differ 

 from P. hochstetteri, Pfr. 



The teeth have been described and figured by Captain 

 Hutton ; :;: the formula given is 50-0-50. In the specimen 

 under investigation many of the rows of teeth give the 

 formula 52-0-52. A few of the innermost teeth (fig. 2), 

 usually not more than two on each side, are small and very 

 slender. Occasionally one of these slender spicula-like teeth is 

 somewhat separated from the adjoining teeth, and where this 

 occurs it gives to the row the appearance of a central tooth. 

 Fig. 3 represents the teeth 20 to 26 in one of the rows. 



The kidney is shortly tongue-shaped, in length less than 

 twice its breadth, about half the length of the lung, and about 

 one and a half times the length of the pericardium ; the latter 

 has the usual position on the left margin of the kidney. The 

 ureter continues around the right margin of the kidney, fol- 

 lows the posterior limit of the lung, and opens close to the 

 intestine. From this point the intestine, or rectum, forms a 

 long straight tube. There is a well-marked ridge on the pul- 

 monary wall less than 3 mm. from the side of the rectum, 

 and the narrow area thus defined appears to be the open con- 

 tinuation of the ureter. The above-mentioned ridge examined 

 in section proves to be tubular ; it continues into the tissue of 

 the mantle, and appears to unite with the blood-sinus con- 

 tained therein. The venation of the lung, with the exception 

 of the great pulmonary vein, is very indistinct. This vein runs 

 direct to the auricle, is of considerable breadth, and has an un- 

 dulating, almost convolute, appearance. On approaching the 



* Trans. N.Z. Inst., vol. xiv., p. 153, pi. iv., figs. A, L. 



