34 PROF. T. J. 1»<\.KKER ON CARCHARODON RONDELETII. [Jan, 18, 



c. The Skeleton of the Fins. — In tlie shoulder-girdle I have 

 nothing to add to Haswell's description. The pectoral fin of 

 specimen A exhibits a concrescence of the proximal ends of the 

 mesopterjgial rays not shown in Haswell's figure. The intercalary 

 pieces between the distal ends of many of the rays, referred to by 

 Haswell, are evidently due to longitudinal division of the rays, one 

 of which, in the specimen referred to, was distinctly bifurcated. 



The pelvic girdle and fin are not figured by Haswell : I therefore 

 give a figure of those of the male specimen A (Plate V. fig. 9). 

 Haswell states that the outer extremity of the pelvic cartilage {pu) 

 " is produced into a process with which no fewer than six rays 

 articulate." In my specimen this process is apparently represented 

 by a separate cartilage («), whicli seems to be formed by the con- 

 crescence of the anterior rays, and to be serially homologous with the 

 propterygium of the pectoral fin. 



The first dorsal fin differs only in detail from that described and 

 figured by Haswell, who says of the second dorsal and ventral (so- 

 called anal) fins, that they " are very small, and consist of a few 

 irregular rays without basal plates." I find, on the contrary, that 

 both these fins (Plate V. fig. 10, and Plate VI. fig. 1.5) and especially 

 the ventral (fig. ID) are quite typical examples of the coucrescence 

 of pterygiophores (radial cartilages) to form a basipterygiura. 



4. Alimentary Organs. 



The stomach (specimen C) consists of a wide cardiac (Plate VI. 

 fig. IG, card.st.) and a narrow tubular pyloric (pijl.st.) division. 

 The cardiac division is about 115 cm. long and 75 cm. wide; the 

 pyloric division 104 cm. long by 5 cm. wide. On the right side of 

 the stom.ach, near its oesophageal end, are two hhnd pouches {x.). 



The intestine {int.) is 109 cm. long from the pylorus to the origin 

 of the rectal gland, and 26 cm. in diameter. The spiral valve is 

 regularly disposed, makes 48 turns, and is slightly narrower than the 

 semi-diameter of the gut, so that a narrow central passage is left, as 

 in Alopecias and in some specimens of Raia '. 



The rectal gland {rct.gl.) is 30 cm. long by 3"5 cm. in diameter. 

 The cloaca (fig. 17) is comparatively small, and is divided by a 

 horizontal fold into two chambers, an outer (c/') receiving the ovi- 

 ducts (ovd.ap.), and an inner (cP) receiving the rectum (ret) and 

 the urinary duct (ur.ap.). 



The liver consists of two immense lobes, which fill all the ventral 

 region of the abdominal cavit}'. In specimen C the gland was too 

 much decomposed'for its form and size to be made out, but in D 

 (5 metres long) each lobe was about 135 cm. long, by 102 cm. wide, 

 and fully 30 cm. thick. A gall-bladder is present. 



The spleen and pancreas have the usual characters ; the pancreas 

 (Plate VI. fig. 16, pan.} consisting of a small ventral and a large 



' T. J. Tarker, " On the Intestinal Spiral Valves in the Genus Baia," Trana. 

 Zool. Soc. vol. si. ]i. .50. 



