^ Notes, iv. 5. 221 



has justly observed that his knowledge of this class, both zoological and anatomical, 

 is truly astonishing." 



As to the various species known to him, see iv. 9, Note i ; and, as to their external 

 parts, consult the other notes to that chapter. Here we are concerned only with their 

 internal parts. The digestive organs are thus described {H. A. iv. i) : "After the 

 mouth there is a long and narrow oesophagus. Continuous with this is a large round 

 crop resembling that of a bird. Then comes the stomach like a rennet. The form of 

 this is spiral, like the shell of a whelk. Froni this a thin intestine runs back towards 

 the mouth ; the intestine is however thicker than the Stomach." 



It is I think clear that A. did not mean by the crop (iyoA({)3oy) What moderns call the 

 crop, which is found in rio, other dibranchiate cephalopod than the poulp ; for he 

 expressly says that the poulp and the sepia are precisely aljke so far as these parts 

 are concerned. The crop of the poulp, had escaped his observation. The crop of which 

 A. speaks is what we call the stornach. This is, as he says, of softer consistency 

 in the calamary than in the sepia or the poulp, where it is more muscular. What 

 A. calls the stomach is what we look on as the commencement of the gut, which 

 communicates with a membranous dilatation or sac, that is mo^e or less spirally 

 twisted, and is found in calamary, sepia, and poulp alike,^ though more developed in the 

 first of the three, where it may be not inaptly compared to the spiral body of the whelk. 

 The oesophagus is, as he justly says, long and narrow. Thus his description is accurate, 

 with the excejftion, that he does not notice the crop of the poulp; while he gives 

 different names to the cavities from those we use. 



12. The accotint of the ink-bag, and of the differences of size and position it presents 

 in the different speciesj is accurate ; it being of course understood that the tetrabranchiate, 

 cephalopods, that have no ink-bag, were unknown to Aristotle. 



13. The mytis is identical with the mecon, which exists in all Crustacea {ff. A. iv. 

 2, 22) ; is a bag containing excretory ^natter (JI. A. i\. 4, 24) ; placed near the hinge 

 in bivalves, and in the spiral part of the shell in Turbinata {H. A. iv. 4,. 22), being spiral 

 itself, in the whelk for instance {H. A. iv. 4, 18). This can be nothing else than the 

 liver ; and Kohler's notion that the glandular appendages of the veins are meant 

 {Todd^s Cycl. i, 539) is out "of the. question. Though A. often states that bloodless 

 animals have no proper viscera, he makes ari exception in the case of the mytis [H. A. 

 iv. I, 19). It was doubtless the dull red or violet colour of this organ which gained 

 it this distinction ; the viscera being, as he supposed, formed of coagulated blood 

 (cf. iii. 8, Note 2). In fact he speaks latef on in this chapter of the mytis as "resembling 

 blood," and believed it to rep;-esent the heart. 



14. That is to say, have longer tentacles or arms than the rest (cf. iv. 9, Note 15). 



15. In reality all these Cephalopods have the faculty of changing colour ; but the 

 phenomenon is most conspicuous in the poulps (cf. Cuvier, R. ^«, iii. 10). 



16. The Sepiadse, and still more the calamaries, are pelagic ; the poulps are littoral. 



17. Cf. iv. I, Note 4. 



18. The internal shell of the sepia consists of a broad spongy calcareous plate, the 

 well-known cuttlefish-bone, of the shops. That of the calamary is a thin horny plate, 

 called, from its shape, " the pen.'' In the poulp there is no internal shell at all, 



19. Cf. ii. 4, "Note 4. . . . 



20. That fear does thus affect the bowels and the bladder is a fact well known to 

 physiologists. To the examples given at ii. 4, Note 5, may be added not only men, but 

 cattle, dogs, cats, and monkeys j in all of which Mr.- Darwin has noticed the phenomenon 

 {Expr. of Emot. p. 77). • . • . 



