DISEASES OF THE LARYNX AND TRACHEA. 437 



These new growths, varying in size and form, produce greater or less 

 difficulty in deglutition ; often after great effort only fluids can be 

 swallowed. Sometimes suffocation and vomiting occur ; wasting is a 

 regular result. Curability depends on the condition and number of the 

 growths, and on whether they can be reached. Polypi with narrow pedicles 

 may be torn off and discharged during violent vomiting. In carnivora, 

 as in man, these usually have their seat in the pharynx or close behind it, 

 and during vomiting may be thrown forward into the pharynx, and can 

 then be removed, as shown by a case reported by Diericx. Where the 

 swelling in the neck portion of the oesophagus can be detected externally. 

 which, however, is seldom the case, it may be removed by performing 

 oesophagotomy. The uncertainty of diagnosis during life generally prevents 

 rational treatment. Lorenz saw a horse die from pleurisy, and found 

 a carcinoma which had led to rupture of the oesophagus. Molni detected 

 a tumour in the left oesophageal furrow in a cow, which, after each feeding 

 time, showed tympanites. He regarded the case as one of goitre. 



VIII. DISEASES OF THE LARYNX AND TRACHEA. 



(1.) INJURIES, INFLAMMATIONS, AND TUMOURS IN THE 

 LARYNX. (LARYNGITIS. PERILARYNGiTTS.) 



Only in carnivora is the larynx accessible to direct inspection. This 

 is effected for clinical purposes by drawing out the tongue and depressing 

 it with some blunt instrument (spatula). The laryngeal mirror used by 

 Nawratil and Schmidt is of little value, and is seldom used on account 

 of the animal's resistance. Until recently, inspection of the larynx in 

 the larger animals appeared impossible, but Polansky and Schindelka, 

 with the assistance of the Vienna optician Leiter, have constructed instru- 

 ments for examining the larynx and pharynx of the horse, and amongst 

 others the rhino-laryngoscope, which affords not only clear but extensive 

 views of this region. Its construction is complicated, its use requires the 

 electric light, and its application in veterinary practice has accordingly 

 as yet been limited ; but it is very serviceable for clinical observation 

 and for teaching. 



On account of its protected position between the branches of 

 the lower jaw, the larynx seldom suffers from injuries from without, 

 though sharp foreign bodies swallowed with the food may pierce 

 and inflame the mucous membrane. Rowland removed from the 

 pharynx of a horse a fish-hook, which had penetrated the larynx. 

 Injuries of the larynx occur oftener than is supposed, but not so 

 frequently as those of the pharynx, and produce either acute or 

 chronic inflammatory processes. The acute are clinically comprised 

 under acute laryngitis, and are considered in the text-books on special 

 pathology and therapeutics. The chronic lead to proliferation of 

 connective tissue in the neighbourhood of the laryngeal cartilages 

 (perilaryngitis chronica fibrosa) or pus formation. 



Kiihnert saw a case of suppurative laryngeal perichondritis in 



