THE CEPHALOPODA. 



$250. 



thelium. It begins behind the pharynx by a straight, long, very narrow 

 cesophagus, whose internal surface is longitudinally plicated. After leaving 

 the annular opening of the cephalic cartilage, it enters the peritoneal cavity, 

 which is highly developed and divided by constrictions into several cham- 

 bers. With the Loligina, the oesophagus is of uniform calibre throughout 

 to the stomach ;^^' but with the Octopoda, it is abruptly dilated, upon leav- 

 ing the cephalic cartilage, into a kind of crop, which extends to the stom- 

 ach.^-' With Nautilus, also, it is dilated, but gradually, into a very large 

 crop, which communicates with the stomach by a narrow, short canal.® 



The Stomach invariably consists of a sac lined with a very solid epi- 

 thelium, which is plicated longitudinally ; the Cardia and Pylorus are 

 situated close to each other at its upper portion. ^^* As soon as the intes- 

 tine has left the pylorus, it forms a Caecum which has glandular, plicated 

 walls, and, with many genera, is more or less elongated and spirally 

 convoluted.''*' The rest of the intestine is short, rarely flexuous, and ex- 

 tends from the peritoneal sac to the base of the funnel,'"* where it termi- 

 nates in a small anal prolongation, the borders of which are often fringed ; 

 sometimes it has two lateral tongue-shaped valves, placed opposite each 

 other, and by which the anal opening can be closed.''* 



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The Salivary organs of the Cephalopoda are highly developed, and 

 consist of a superior and an inferior pair, the former of which is some- 

 times, but the latter very rarely, wanting. The superior pair consists of 

 two glandular lobes situated at the posterior extremity of the pharynx, 

 which open by short excretory ducts behind the root of the tongue.'^* 

 The inferior pair lies on each side of the oesophagus at the upper portion 

 of the peritoneal sac, directly behind the cephalic cartilage. These 

 organs, usually of a dull-white color, are composed of numerous inter- 



1 Sepia, Loli^o, Onychnteuthis, Loligopsis, 

 Sepiola, kc. 



Si Cuvifr, Mem. PI. IV. fig. 1, 2, b.; Wagner, 

 Icon. zoot. Tab. XXIX. fig. 14 {Octopus); ran 

 Beneden, loc. cit. PI. III. fig. 3, d. {Argonauta) ; 

 Firussac, loc. cit. OctopiiK, PI. XIII. tig. 9, 10, 

 ArgonautCL, PI. I^. fig. 1, 2 ; and Delle Chiaje, 

 l)escriz. Tav. XV. fig. 3 {TremoclopuK). 



3 Owen, On the Nautilus, PI. IV. or Isis, Taf. 

 III., or Ann. d. Sc. Nat. PI. II. fig. 1. 



4 See tlie figures in Cuvier, Brandt, Firuasac, 

 Owen, &c. The stomach of Octopus and Eledone, 

 from its muscular walls, and its almost horny 

 fpithelium, resembles very much the gizzard of 

 birds. 



3 X ills caecum, regarded as a second stomach by 

 many zootomists, corresponds, probably, to the py- 

 loric apjjendages of fishes. With Nautili/s, it is 

 a round sac, the internal surface of which has 

 lon»itudnial folds, so that its cavity has a lamel- 

 lated appearance (Oioen, On the Nautilus, p. 25, 

 PI. IV. y. and PI. VIII. fig. 8, f., or Isis, Taf. II. 

 III., or Ann. d. Sc. Nat. PI. II. fig. 1, y. PI. IV. 

 fig. 8, f.). With Loligop.iis, and Sepiola, this 

 round sac is lined internally with spiral folds 

 CGrrmt, Transact. Ux;. cit. p. 25, PI. II. fig. 7, g. 

 and p. «1, PI. XI. fig. 7, 8, c). With Sepia, and 

 various Octopmia, it is oblong, and lined internally 

 with transverse spiral folds supiiorted by a kind 

 ot mesentery ; — see f^an Beneden, loc. cit. PI. 



III. (Argonauta) ; Delle Chiaje, Descriz. Tav. 

 XIII. XV. XVIII. (Tremoctopus. Sepia, and 

 Loligo) ; Cuvier, Mem. PI. IV. fig. 1, 2, f.: M'ag- 

 ner, loc. cit. fig. 14, f. (Octopus) ; Home, Lect. on 

 Comp. Anat. PI. LXXXIII. {Loligo sagittata) ; 

 and Firussac, loc. cit. But, in this respect, Loligo 

 vulgaris forms an exception ; its caecum is 

 straight, oblong, and its thin walls are without in- 

 ternal plicae : see Meckel, Syst. d. vergleich. 

 Anat. IV. p. 199, and Delle Chiaje, Descriz. &c. 

 Tav. XVI. tig. 5, s. 



ß The intestine is straight with Argonauta^ 

 Loligo, Sepia, Sepiola, and otlier Loligina ; but 

 it ib fle.xuous with Octopus, Eledone, and Nau- 

 tilus. 



' Owen (Tran.sact. of the Zool. Soc. II. PI. XXI. 

 fig. 16) has found two lateral valves projecting into 

 the anal cavity with Sepioteuthis. I have seen 

 two similar with a Tremoctopus Rathke (Mem. 

 de St. Petersburg, loc. cit. p. 160 PI. II.) hag 

 found them replaced, with Loligopsis, by two 

 tentaculiform prolongations. 



1 Cuvier, Mem. p. 27, PI. III. fig. 3, e. {Octo- 

 pus) ; Ferussac, loc. cit. Octopus, PI. XII. fig. 6, 

 n. PI. Xin. fig. 9, n.-, Owen, Cyclop. I. p. 532, 

 fig. 218, i. {Onychoteuthis). With Nautilus, 

 Owen found no lower, and only the traces of the 

 upper glands (On the Nautilus, p. 23, PI. VIII. fig. 

 7, g., or Isis, p. 20, Taf. II., or Ann. d. Sc. Nat. p. 

 114, PI. IV. fig. 7, g.). 



