THORAX. 



1016 



Fibrous tumours. A small fibrous tumour 

 is occasionally developed in the areolar tissue 

 of the scrotum. It may acquire the size of the 



and heart, and by its movements to maintain 

 the function of respiration. 



Generally by the term thorax is understood 



testicle, and being firm and of an oval form, a cavity set apart for the respiratory organs. 



resembles a supernumerary gland. I have 

 met with only one case of this form of tumour. 

 Dr. Mott, of the United States, excised an 

 enormous mass from the scrotum of a man 

 about seventy-three years of age. The scrotum 

 was twelve to fifteen times its ordinary bulk, 

 and was filled with tumours of a stony hard- 

 ness, from the size of a nutmeg to that of a 

 large pea. The tumours had all a very white 

 appearance, and the integuments over two 

 or three of the largest, having been ulcerated 

 for upwards of a year, poured forth a foetid 

 discharge, together with a white substance 

 resembling mortar. The disease was upwards 

 of twenty years' duration. I have no doubt 

 this disease was originally of a fibrous cha- 

 racter. The calcareous matter and other 

 changes resemble those occasionally observed 

 in large fibrous tumours of the uterus. A 

 tumour of a similar character and of great 

 size was removed by operation from the 

 scrotum of a man in St. Vincent's hospital, 

 Dublin, by Dr. O'Ferrall.* 



BIBLIOGRAPHY. Anatomy. De Graaf, DeYir. 

 Organ. Gener. Lugcl. Bat. 1668. Monro, Essays and 

 Observations, vol. i. Edinb. 1754 ; also De Testibus 

 et de Semine in variis Animalibus. Diss. Inaug. 

 Smellie. Thes. Med. ii. 317. 1755. Hunter, W. Me- 

 dical Commentaries, 17G2. Warner, An Account of 

 the Testicles, 1774. Palletta, Nova Gubernaculi 

 Testis Hunteriani et Tunicas Vaginalis Descriptio, 

 1777. Brugnoni, De Testium in Fcetu positu, &c., 

 178.3. John Hunter, A Description of the Situation 

 of the Testis in the Fostus, with its Descent into the 

 Scrotum, (Animal CEeonomy), 1786. Seiler, Observ. 

 de Testiculorum ex Abdomine in Scrotum descensu. 

 Lepsia?, 1817. Wilson, Lectures on the Urinary and 

 Genital Organs, 1821. Sir Astley Cooper, Observa- 

 tions on the Structure of the Testis, 4to., 1830. 

 Lauth, Memoir de la Socie'te d'Hist. Nat. de Stras- 

 bourg, t. i. 1830. Krause, Mailer, Archiv. fur An- 

 atomic, 1837. Gulliver, Proceedings of Zoological 

 Society, 1842. Cm-line/, Treatise on the Testis, 1843. 

 E. Huschke, Encyclopedic Anatornique, t. T. Paris, 

 1845. 



Morbid Anatomy of the Testicle. Pott, On 

 Hydrocele and other Diseases of the Testicle, 1767. 

 Bell, B. On Hydrocele and other Diseases of the 

 Testis, Edinb. "1794. Wolf, L. De Sarcocele, Er- 

 lang. 1799. Sir Astley Cooper, Observations en the 

 Diseases of the Testis, 1830. Baring, Ueber den 

 Markschwamm der Hoden, Gbtting. 1833. Ku^ill, 

 Observations on the Testicles, 1833. Brodie, Lec- 

 tures on Diseases of the Testicle, Lond. Med. Ga- 

 zette, vol. xiii. 1834. Berard, Journal desConnaiss. 

 Me'dico-Chirurgic. pour 1'anne'e 1835. Velpeau, Diet, 

 de Me'd. t. xv. Landouzy, Du Varicocele, Paris, 

 1838. Curling, Treatise on the Diseases of the 

 Testis, 1843. Maladies des Testicules Biblio- 

 theque du Me'dicin Practicien, t. iv. Paris, 1M6. 

 Yidul (de Cassis), Traite de Pathologic, t. v. 1846. 



(T. B. Curling.) 



THORAX (dt&pajj from Sopw to leap, be- 

 cause in it the heart beats). " The habitation 

 of the breathing parts." That part of the 

 human body destined to contain the lungs 



* Dublin Hospital Gazette. Feb. 1845 



Such a cavity, however, is not essential to 

 respiration : a respiratory surface only is es- 

 sential. This must exist in every animal, 

 whilst a separate thorax is found perfect only 

 in mammalia. 



The development of the respiratory surface 

 may take place in three ways. 



1st. Either towards the interior of the 

 body, in the form of ramified or sacculated ca- 

 vities ; or, 



2ndly. Towards the exterior, in the form of 

 lamellated, ramified, pectinated, tufted, cili- 

 ated, or pinnated processes called " bronchia;" 

 in which Nature seems to have exhausted all 

 imaginable varieties of form ; and, 



3rdly. By a system of tubes ramified to ex- 

 treme fineness, either in an especial cavity or 

 thorax, or in a cavity common to these 

 organs and to others destined for the diges- 

 tive function. 



The movements necessary to respiration, 

 are modified according to the form of the re- 

 spiratory apparatus and the nature of the 

 medium to be respired, whether pure air or 

 air contained in water. 



In some of the lowest animals, the respira- 

 tory movements are the same as those of loco- 

 motion, as in the monad and other infusorial 

 animalcules. In all animals, even when the 

 respiratory organs are contained in a true 

 thoracic cavity, the frame-work serves other 

 purposes besides that of drawing in and 

 throwing out air ; it gives attachment to the 

 largest muscles of the upper extremity, whe- 

 ther prehensile or locomotive. In man parti- 

 cularly, we find the respiratory muscles con- 

 tribute to such acts as coughing, sucking, 

 sneezing, yawning, sighing, singing, vomiting, 

 as well as the innumerable articulate sounds 

 of language. 



Distinct respiratory movements, as depen- 

 dent upon alternate contractions and dilata- 

 tions of a thoracic cavity, are most regular, or 

 at least, they have been more noticed, in 

 mammiferous animals. The thoracic cavities 

 of mammiferous animals have much of the 

 mechanism of respiration in common. They 

 all possess a vertebral column or spine, and 

 that peculiar frame-work of ribs, together with 

 a sternum, so articulated together as to move 

 in breathing. 



There is likewise a great similarity of mus- 

 cular arrangement around the thoracic cavity; 

 and consequently the respiratory movements 

 closely resemble each other. 



Although the boundaries of the thorax are 

 generally the parts which move in respiration, 

 and these are generally composed of vertebrae 

 ribs and sternum, yet some animals may 

 have either all of these, or they may lack some 

 of them, or, if present, they may not move 

 in the breathing function. Frogs have a ster- 

 num, but no ribs ; serpents have ribs, but no 

 sternum ; tortoises have ribs, vertebrae, and 



