PLATE 58. 



Intestines of ANTACEA and CERATODUS. \ 



Fig. 1. Heptranchias PERLO. M. C. Z. 945 (Page 21). Fig. 2. Cephaloscyllium umbratim 

 M.C.Z. 1044 (Page 80). Fig. 3. Isurus punctatus. M. C. Z. 1249 (Page 36). Fig. 4. Hemigaleui 

 PECTORALis. M. C. Z. 847 (Page 150). Fig. 5. Pristiophorus japonicus. M. C. Z. 1045 (Pag 

 246). Fig. 6. Ceratodus fosteri. M. C. Z. 9827. 



There are marked differences between the intestine of the Plagiostomia and that of Ceratodufc 

 The stomach of the former is distinctly separated from the spiral intestine, while that of the latter is ; 

 continuation forward of the spiral it.self . The stomach and intestine of Ceratodus, fig. 6, form a con 

 tinuous spiral the characters of the inner surfaces of which change from the villous of the stomach propi' 

 to the absobcnt of the intestine in a single turn of the winding course. The number of turns in Ceratodu 

 is nine or ten; the axis of the spiral is firm and muscular. The number of turns in the intestinal spiral ( 

 the Plagiostomia varies in those dissected here from four in Hemigaleus, fig. 4, to thirty-nine in Isuru- 

 fig. 3. 



