12 ZOOLOGY OF THE VOYAGE OF H.M.S. SAMARANG. 



agreeing with the Decapods. The branchial hearts are devoid of the appendage in the 

 Octopods, but this is present in the Decapods, and equally characterizes the Spirula. In the 

 Octopods the gullet dilates into a crop, but not in the Decapods, neither in the Spirula, in 

 which, as in other Decapoda, it is remarkable for its length and tenuity. In Octopus the 

 liver consists of one lobe, and has the ink-bladder imbedded in it : in Sepia the liver consists 

 of two lobes, and the ink-bag is not in any way connected with it ; the Spirula agrees with 

 the Cuttle-fish in these respects. In all Octopods the hepatic ducts are simple; in all 

 Decapods they are complicated with numerous small blind pouches, which have been regarded 

 as a pancreas ; these cystic follicles are equally present in Spirula, So far, then, as the 

 organization of the Spirula is known, its modifications are those that characterize the 

 Decapodous type of the Dibranchiate structure in the class Cephalopoda. If, therefore, the 

 accuracy of Lamarck's highly important original description and figure of the animal, inasmuch 

 as relates to the superaddition of two long peduncles to the eight ordinary arms, had not 

 been confirmed by Mr. Percy Earl's discovery of the entire animal, figured in the Annals 

 of Natural History, vol. xv. pi. 1 5, and more accurately in Mr. Lovell Reeve's Elements of 

 Conchology, part 1, pi. A., fig. a, b, c, and which unique specimen is now in the unrivalled 

 conchological cabinet of Mr. Hugh Cuming, the confidence that had been placed in Lamarck's 

 accuracy would have been fully justified by the well-marked repetitions of the decapodous 

 modifications of the Cephalopodic structure which the dissection of Sir E. Belcher's specimen 

 has brought to light. 



The mere description of appearances, even of the interior structure, still less of the 

 exterior surface of an animal, without the deductions which they legitimately yield, is of 

 comparatively small value to the philosophic Naturalist ; for of what value are facts until they 

 have been made subservient to establishing general conclusions and laws of correlation, by 

 which the judgment may be safely guided in regard to future glimpses at new phenomena 

 in Nature, such as those which the figures and descriptions of Lamarck and Peron afforded 

 of the Spirula, before the publication of the anatomy in the Annates d'Anatomie, and in the 

 present Work? The combination of deduction with observation in Natural History has, 

 indeed, been so rare, and the grounds for confidence in such laws of correlation as have served 

 to deduce one type of Cephalopodic structure from the absence of an ink-bag, and another from 

 its presence, have been so recently attained, and are appreciated by so few, that the scepticism 

 in the deductions from such laws in regard to the Spirula may be readily pardoned. In 

 perusing the observations of so respectable an authority as the author of the article "Turrilites " 

 in the Penny Cyclopaedia, tending to show the insufficiency of the grounds of my separation 

 of Spirula and Belemnites from the Nautilus, and other Tetrabranchiate Cephalopods with 

 chambered shells ; and the statement of the author of the Elements of Conchology (p. 11), 

 that " a difference in the number of branchiae seems scarcely of sufficient importance to 

 warrant the association of the Spirula with the Argonaut, separate from the Nautilus;" I 



