78 THE DISEASES OF THE DOG. 



Filaria sanguinolenta (Schneider and Lewis) has been 

 found by Dr. Lewis in the oesophagus, thoracic aorta, 

 and neighbouring parts of the pariah dogs of Calcutta. 

 Schneider found it (or a closely allied form) in the walls 

 of the stomach. Dr. Manson has found it in Amoy and 

 considers that all dogs there which have attained any con- 

 siderable age are or have been its host. It is debated 

 whether the embryonic filarise in the blood are of this 

 form or of F. immitis; the latter view is most probable, and 

 Rivolta says that when embryos are found in the blood 

 the mature F. immitis can always be found in some part or 

 other of the body. There are no absolutely diagnostic 

 symptoms of their presence during life. " On opening 

 the thorax of an affected animal and drawing the heart 

 and left lung over to the right side, the straight part of 

 the thoracic aorta may be seen studded with small tumours, 

 ranging in size from a small pea to a bean, and the ante- 

 rior and lateral surfaces of the oesophagus bulged out by 

 tumours perhaps as large as a walnut, and where several 

 of these are in juxtaposition a large lobulated tumour 

 may conceal the oesophagus altogether. To the touch 

 these tumours are hard, though at points there may be a 

 feeling of deep fluctuation. If the aorta is excised and split 

 open, its inner surface is found, at the points correspond- 

 ing to the tumours on the outside, to be more or less deeply 

 sacculated, the inner coat roughened and the outer coats 

 thickened. In the latter worms at different stages of 

 development may be found, or perhaps the sacculation 

 and external bulging may only be evidence that a worm 

 has once been there, but has disappeared. When the 

 worm has reached a certain stage in its development a 

 minute orifice can be seen on the inner surface of the 

 tumour, communicating with the cavity containing the ani- 

 mal. Through this hole a purulent fluid can be expressed ; 

 this on microscopic examination is found to be loaded 

 with characteristic ova, and cells resembling those of 

 ordinary pus. The tumours in the oesophagus occupy 

 the muscular wall, and generally are much larger than 

 those of the aorta. On the inner surface of the oesophagus 



