THE RESPIRATOEY APPARATUS. 327 



Interstitial pneumonia has been described by some 

 autbors under the beading empbysema. Tbe latter state 

 is one of its results. Besides tbe causes already mentioned 

 it may be due to tbe " constant presence of effete matter 

 in tbe blood. Tbe large amount of areolar tissue of tbe 

 lungs of tbe ox must be considered a predisposing cause. 

 Tbe symptoms manifested by an animal suffering from 

 tbis form of pneumonia are obscure. Tbe patient is 

 manifestly unwell, and tbere is increasing anaemia. Tbe 

 skin is yellow and scurfy, and tbe bowels are irritable. 

 Auscultation sbows absence or diminution of tbe vesicular 

 murmur in tbe diseased and increase in tbe bealtby parts, 

 but percussion does not give definite results. Finally, tbe 

 anaGmia proves fatal, and after deatb tbe lungs are found 

 firm, pale, and markedly empbysematous. Tbe rigbt side 

 of tbe beart is bypertropbied. Cases of tbis kind are 

 cbronic and unsatisfactory. Stimulant tonics and good 

 feeding witb careful nursing are about tbe only means at 

 our disposal. Tbe absorbent action of iodide of potassium 

 may be tried. 



Tbe effects of entry of non-respirable gases into tbe 

 lungs or of tbe passage of fluid matters in considerable 

 quantity down tbe tracbea are, primarily, aspbyxia, but if 

 tbe animal be able to rally from tbis tbe catarrhal form of 

 pneumonia supervenes ('Veterinarian,'' vol. xiv, p. 257). 



Sometimes Echinococcus cysts are found in tbe lungs. 

 Tbey may be present in considerable number without our 

 attention having been drawn to any sign of ill health in 

 tbe host. The cysts are formed by tbe areolar tissue, 

 condensed and altered by the presence of the parasite 

 and enclosing it on every side. They may be deeply 

 embedded in tbe substance of the organ or projecting on 

 the surface, and sometimes are in tbe stage of calcareous 

 degeneration. Wounds of the Lungs are not so frequent, 

 for these organs are very elastic. An interesting case of a 

 " Cyst in the lung,^^ due probably to the passage of a 

 foreign body from the stomach, is given by Mr. G errard, of 

 Romford ('Veterinary Journal,^ vol. iv, p. 163). A laceration 

 of this organ leads to baBmoptysis, but repair somewhat 



