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The salivary glands raentioned above form a layer which covers 

 the oesophagus like a sheath. The glands lie in the spaces which 

 are left by the muscular fibres, crossing each other in all direc- 

 tions. From each glaud an excretory duet issues , as we have 

 seen, which in combination with other ducts forms a small bundie. 



As well on longitudinal as on transverse sections , these bundies 

 are met with everywhere ; they find tlieir way to the jaw pas- 

 sing the glands which are situated nearer the mouth. Those small 

 bundies unite successively in order to form bigger ones and finally 

 three equal mainbundles are forraed, corresponding to the three jaws. 



It was this maiubundle, which by former Zoologists was des- 

 cribed as a muscle, whilst the fine buudles were not known 

 as yet. 



The mainbundle enters the jaw between tlie two muscular layers , 

 but spreads out fanlike towards the sharp edge of the jaw (fig. 1 kb). 



The transverse section of the bundie near the basis of the jaw 

 is more or less circular; on its way to the edge of the jaw it 

 becoraes elliptical, corresponding to the shape of the jaw itself. 

 Near the sharp edge the main buudle gets separated into a great 

 uumber of smaller bundies in accordance to the uumber of den- 

 ticules and these small bundies open between the teeth. 



Leuckart states , that the glandducts of the secundary bundies 

 meet into a bottlelike collecting duet, which is situated between 

 two foUowing teeth. 



I have seen nothing of this collecting duet, I believe that the 

 excretory ducts terminate in the spaces between two neighbor- 

 ing teeth. 



In Aulastomum gulo (fig. llh) little holes are found under 

 the denticules, where the glandducts pour out their contents. 



Aulastomum gulo has, as is known, only twelve teeth and 

 thus the mainbundle is divided only into eleven bundies , hence 

 the secundary bundies are easier studied here than in Hirudo 

 medicinalis, which possesses about hundred denticules. 



On cutting the jaw of Aulastomum or of Hirudo longitudinally 

 through its sharp edge the fanlike distribution is very well seen. 



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