MOTION. 



407 



probable to those who have any knowledge of 

 the animal,) I tried it also in that position ; 

 but though it struggled to regain its former 

 posture, no use was made of the hind claw. 

 I tried several other methods of effecting the 

 object I had in view ; but as all proved futile, 

 I am convinced that some other use must be 

 found for the spur than as an offensive weapon. 

 I have had several subsequent opportunities of 

 repeating the experiments with animals not in a 

 wounded state, and the results have been the 

 same."* 



Evidence to a like effect is given by the 

 zoologists of the French expedition in the Astro- 

 labe, in reference to the male Echidna.f An 

 objection to the theory of the spur and gland 

 being a defensive apparatus is their absence in 

 the female. 



Since then this apparatus forms a sexual 

 character, it may be presumed that its func- 

 tion is connected with that of generation. 

 Whether the spur be a weapon for combat 

 among the males, or, like the spiculum amoris 

 of the Snail, be used to excite the female, the 

 injected secretion being an additional stimulus, 

 or whether the spur be mechanically useful 

 in retaining the female during the coitus, are 

 conjectures which must be verified or disproved 

 by actual observation. 



BIBLIOGRAPHY. Shaw, Naturalists' Miscellany, 

 1798. General Zoology, vol. i. 1800. Blumenbach, 

 Philos. Transactions, 1800 ; and Voigt's Magazin 

 fiir den neuesten Zustand der Naturkunde, Band 2, 

 1800. Hmne, Philos. Transactions, 1802, pp. 67 

 and 356. Ibid. 1819. Lectures on Comparative 

 Anatomy, passim. Cuvier, Lemons d'Anatomie 

 Comparee, 1799-1805, passim. Ossemens Fossiles, 

 4to. vol. v. 1823. Peron and Lesueur, Voyage de 

 decouvertes aux Torres Australes, 1807. Meckel, 

 Beitrage zur Vergleichenden Anatomic, 1808. Fro- 

 riep's Notizen, 1824. Ornithorhynchi paradoxi de- 

 scriptio anatomica, fol. 1826. De Blainville, Dis- 

 sertation sur la place que la famille des Orni- 

 thorynques et des Echidnes doit occuper dans les 

 series Naturelles, 4to. 1812. Bulletin de la Societe 

 Philomathique, 1817. Nouvelles Annales du Mu- 

 seum, torn. ii. 1832. Geojf'roy St. Hilaire, Ana- 

 tomic Philosophique, torn. i. 1818. Memoire sur 

 les Glandes Abdominales des Ornithorhynques 

 faussement presumees mammaires, lesquelles se- 

 cretent, non du lait, mais du mucus, &c. Gazette 

 Medicale de Paris, 1833. Sur des Glandes Abdo- 

 minales chez 1'Ornithorhynque dont la determina- 

 tion, comme mammaires, fut en Allemagne, et est 

 de nouveau en Angleterre un sujet de controversie, 

 8vo. 1833. Rudolphi, Abhandlungen der Berliner 

 Akademieder Wissensthaften, 1829. Jaffe, Thesis 

 inaug. de Ornithorhyncho paradoxo, Berolin, 1823. 

 Traill, Edinburgh Philos. Journal, 1822. Hill, 

 Linnaean Transactions, vol. xiii. 1822. Kno.r, 

 Wernerian Transactions, vol. v. Van der Hoeven, 

 Nova Acta Physico-Medica, torn. xi. 1823. Pander 

 and D' Alton, Skelete der zahnlosen Thiere, 1825. 

 Grant, (Dr. R.) Annales des Sciences Naturelles, 

 1829, torn, xviii. Muller, De Glandularum Secernen- 

 tium Stiucturfi penitiori, fol. 1830. Owen, Philos. 

 Transactions, 1832, 1834. Proceedings of the 



* Zoological Transactions, vol. i. p. 236. 



t " Nous n'avons point entendu parler d'accident 

 occasionne par cette piqure, et nous-memes nous 

 avons touche, irrite cet Echidne sans qu'il ait ja- 

 mais cherche a se servir de son anne, pas meme 

 lorsque nous exercions sur clle une assez forte pres- 

 sion." Zoologie du Voyage de 1'Astrolabe, p. J24. 



Zoological Society, October, 1832, March, 1833. 

 Zoological Transactions, vol. i. 1834. Bennett, G, 

 Zoological Transactions, 1834. Eydoux Sf Laurent, 

 Voyage de la Favorite, 1836, 8vo. 



(R. Owen.) 



MONSTROSITY. See TERATOLOGY. 



MOTION ANIMAL, ANIMAL DY- 

 NAMICS, LOCO-MOTION, OR PRO- 

 GRESSIVE MOTION OF ANIMALS. 



Amongst the infinite number of objects pre- 

 sented by the Deity to our contemplation in 

 the sublime spectacle of the universe, there are 

 none, relating to the economy of animal life, 

 more important in their consequences, more 

 calculated to awaken inquiry, or deserving 

 of more profound research, than the phe- 

 nomena of progressive motion in man and 

 animals. 



Life, in virtue of which animated beings 

 possess sensation and exhibit the play of the 

 vegetative functions, endows the muscular 

 system with contractility, and is the funda- 

 mental cause of all the motor power of 

 animals. 



The theory of the progressive motion of 

 animals presents a most extensive field for 

 anatomical and physiological inquiry, far too 

 extensive indeed for the space here allotted to 

 this subject ; it will therefore be treated only in 

 outline. The automatic, and several of the 

 voluntary motions which belong to the vegetative 

 functions of the animal economy, though de- 

 rived from the same source as those of progres- 

 sive motion, will not be included in this investi- 

 gation. 



The theory of locomotion relates to those 

 mechanical functions by which animals are 

 capable of changing their relative positions 

 or distances with respect to surrounding ob- 

 jects supposed to be stationary or fixed. 



The locomotive organs of the higher animals 

 are composed of a system of levers of various 

 forms, orders, and dimensions, so united or ar- 

 ticulated at the joints as to give them the re- 

 quisite mobility as well as direction of motion. 

 The fulcra to these levers are the earth, the 

 air, or the water; the active agents of mo- 

 tion are the muscles which constitute a 

 complex system of contractile organs, firmly 

 attached to the levers, whereof the points of 

 connexion, amount of contraction, and direc- 

 tion of force, communicate to the levers, to 

 which they are firmly attached, all the move- 

 ments necessary for progression. 



The progression of some animals, such as 

 the Annelida and Ophidian Reptiles, is effected 

 by the alternate contraction or flexion and 

 elongation, or by undulatory movements of the 

 body ; in others, as Bipeds, Quadrupeds, 

 Fishes, Birds, Sec., by the alternate approxima- 

 tion and angular separation of the levers which 

 form the organs of progression. These prin- 

 ciples apply to animals, whether their levers 

 are represented by wings, fins, or legs, and 

 whether the progression is effected on solids, 

 in water, or in the air. 



The various modes of animal progression 



