: MOTION. 
_ 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 
sture, no use was made of the hind claw. 
b tried several other methods of effecting the 
object I had in view; but as all proved futile, 
_ Iam convinced that some other use must be 
_ found for the spur than as an offensive weapon. 
_ Lhave had several subsequent opportunities of 
__ Yepeating 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- 
_ Tabe, in reference to the male Echidna.t 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- 
_ tio n 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. 
. i : 
__BIBLIOGRAPHY.—Shaw, Naturalists’ Miscellany, 
8. General Zoology, vol. i. 1800. Blumenbach, 
ilos. Transactions, ié00 ; and Voigt’s Magazin 
‘den neuesten Zustand der Naturkunde, Band 2, 
Home, Philos. Transactions, 1802, pp. 67 
356. Ibid. 1819. Lectures on Comparative 
atomy, passim. Cuvier, Legons d’Anatomie 
arée, 1799-1805, passim. Ossemens Fossiles, 
tto. vol. vy. 1823. Peron and Lesueur, Voyage de 
decouvertes aux Terres Anstrales, 1807. Meckel, 
age zur Vergleichenden Anatomie, 1808. Fro- 
otizen, 1824. Ornithorhynchi paradoxi de- 
mathique, 1817. Nouvelles Annales du Mu- 
im, tom. ii. 1832. Geoffroy St. Hilaire, Ana~- 
nie Philosophique, tom. i. 1818. Mémoire sur 
~Glandes Abdominales des ts cat bh 
ement présumées mammaires, lesquelles se- 
nt, non du lait, mais du mucus, &c. Gazette 
cale de Paris, 1833. Sur des Glandes Abdo- 
hinales chez l’Ornithorhynque dont la determina- 
ion, comme mammaires, fut en Allemagne, et est 
uveau en Angleterre un sujet de controversie, 
1833. Rudolphi, Abhandlungen der Berliner 
emie der Wissenschaften, 1829. Jaffé, Thesis 
- de Ornithorhyncho paradoxo, Berolin, 1823, 
l, Edinburgh Philos. Journal, 1822. Hill, 
ean Transactions, vol. xiii, 1822. Knoz, 
rmerian Transactions, vol. v. Van der Hoeven, 
va Acta Physico-Medica, tom. xi. 1823. Pander 
D’ Alton, Skelete der zahnlosen Thiere, 1825. 
ant, (Dr. R.) Annales des Sciences Naturelles, 
29, tom. xviii. Miiller, De Glandularum Secernen- 
m Structura penitiori, fol. 1830. Owen, Philos. 
nsactions, 1932, 1834. Proceedings of the 
__* Zoological Transactions, vol. i. p. 236. 
_ + ** Nous n’avons point entendu parler d’accident 
asionné par cette piqfire, et nous-mémes nous 
" vons touché, irrité cet Echidné sans qu’il ait ja- 
_ mais cherché a se servir de son arme, pas méme 
4 - lorsque nous exercions sur elle une assez forte pres- 
Sion,” —Zoologie du Voyage de l’Astrolabe, p. 124. 
= 
¥ 
407 
Zoological Society, October, 1832, March, 1833. 
Zoological Transactions, vol. i. 1834. Bennett, G. 
Zoological Transactions, 1834. Kydoux & Laurent, 
Voyage de la Favorite, 1836, 8vo. 
. (R. Owen.) 
MONSTROSITY.—See Teratotccy. 
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 
forins, 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, &c., 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 
