364 MUSCULAR MOTION. 



divided into two kinds ; the one forming the muscles of animal life, 

 the other the muscles of organic life. The former, called also striated 

 and striped muscles (see Fig. 147), embrace all the voluntary muscles, 

 as well as the heart, the muscular tissue of the pharynx and upper por- 

 tion of the oesophagus : the latter, called also non-striated or unstriped 

 muscles, constitute the proper contractile coats of the digestive tube 

 from the middle of the oesophagus to the external sphincter ani, as well 

 as those of the urinary bladder, trachea and bronchia, excretory ducts, 

 gall bladder, vesiculse seminales, pregnant uterus and Fallopian tubes; 

 arteries, and to a less degree of the veins. 



The intimate structure of the filaments has given rise to extraordi- 

 nary contrariety of sentiment; some, as Santorini, Heister, Cowper, 1 

 Vieussens, Mascagni, 2 Prochaska, 3 Borelli, 4 John Bernouilli, &c., believ- 

 ing them to be hollow; others, as Sir A. Carlisle, 5 and Fontana, 6 solid; 

 some thinking them straight; others zigzag, spiral, or waved; some 

 jointed; others knotted, &c. &c. 7 Borelli and J. Bernouilli announced, 

 that each fibre consists of a series of hollow vesicles, filled with a kind 

 of spongy substance or marrow; the shape of the vesicles being, ac- 

 cording to the former, rhomboidal, according to the latter, spheroidal. 

 Deidier conceived it to be a fasciculus, composed of an artery, vein, and 

 lymphatic, enveloped by a nervous membrane, and held together by 

 nervous filaments: Prochaska, to consist of bloodvessels turned spi- 

 rally around an axis of gelatinous or fibrinous substance, into the in- 

 terior of which the blood rushed at the time of contraction. He says, 

 that the visible fibres are not cylindrical, as they had been described 

 by many observers, but of a polyhedral shape ; and that they are gene- 

 rally flattened, or thicker in one direction than in the other. All are 

 not of the same diameter: they differ in different animals, and in dif- 

 ferent parts of the same animal; and are smaller in young subjects. 

 The filaments or ultimate fibres, which can only be seen with the micro- 

 scope, have the same shape as the visible fibres : they are, however, 

 always' of the same magnitude. Sir A. Carlisle, 8 whose opinions, on 

 many subjects at least, are not entitled to much weight describes the 

 ultimate fibre as a solid cylinder, the covering of which is a reticular 

 membrane, and the contained part a pulpy substance, regularly granu- 

 lated, and of very little cohesive power when dead. The extreme 

 branches of the bloodvessels and nerves, he says, are seen ramifying 

 on the surface of the membrane enclosing the pulp, but cannot be traced 

 into the substance of the fibre. Mr. Bauer 9 and MM. Provost and 

 Dumas 10 differed essentially from the observers already mentioned. 

 Mr. Bauer found, that the muscular fibre was composed of a series of 

 globules, arranged in straight lines; the size of the globule being 



1 Myotomia Reformata, Lond., 1724. a Prodrome, p. 97. 



3 Oper. Minor., P. i. 198. 



4 De Motu Animalium ; addit. Johan. Bernouilli, M. D., Meditationes Mathematic. Mus- 

 culorum, Lugd. Bat., 1710. 



s Phil. Trans, for 1805, p. 6. 6 Sur les Poisons, ii. 228. 



7 Elliotson's Physiology, p. 476. 8 Op. citat v 



9 Sir E. Home, Lectures on Comp. Anat., v. 240, Lond., 1828. 



10 Appendix to Edwards, De 1'Influence des Agens Physiques sur la Vie, Paris, 1824. 



