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A MANUAL OF VETERINARY PHYSIOLOGY 



or glossopharyngeal nerves. If the chorda be stimulated, the 

 vessels dilate, the gland becomes red, the blood flowing from the 

 veins is arterial in tint, and the veins pulsate ; in addition to this, 

 there is an abundant secretion of watery saliva poor in solids. 

 When the sympathetic is stimulated, exactly the reverse is 



Fig. 59. — Diagrammatic Representation of the Submaxillary Gland of 

 the Dog, with its Nerves and Bloodvessels (Foster). 



(The dissection has been made with the animal on its back, and is very diagram- 

 matic.) 



The submaxillary gland (sm. gld.) occupies the centre of the figure ; the blood- 

 vessels supplying it, derived from the carotid artery, a.car., are seen on the 

 left, whilst the duct from the gland sm.d., in which a canula is inserted, 

 is on the right of the figure. 



The chorda tympani nerve, ch.t" '., running in company with the lingual branch 

 of the fifth »./'., is seen to the right and below ; after running together the 

 two nerves separate, the chorda tympani, ch.t., running along the submaxillary 

 duct to the gland. Close to where the two nerves separate is the submaxillary 

 ganglion, sm.gl. 



The sympathetic nerve-supply is shown in the figure to the left and above, the 

 fibres being derived from the superior cervical ganglion, gl.cer.s., and 

 coursing along the bloodvessels to enter the gland. 



The bloodvessels leading from the gland fall into the jugular vein, v.j. 



The arrows indicate the direction of the nervous impulses during the reflex 

 act, ascending to the brain by the lingual, and descending by the chorda. 



observed — viz., the vessels constrict, in consequence of which 

 the gland becomes pale, only a small quantity of extremely viscid 

 saliva flows, which is rich in solids, the blood in the veins becomes 

 very dark in colour, and the blood-stream slows to such an extent 

 that if the veins leading from the gland be cut, the flow from 

 them is less than from a gland at rest. That the increased flow 



