DISTRIBUTION OF SUBCUTANEOUS VESSELS IN GANOIDS IO9 



these forks opened separately into the hyo-opercularis sinus ; 

 the only difference on the two sides being that on the right side 

 (Fig. 3) the openings were further apart. In every case the 

 ventral fork followed along the anterior margin of the first 

 branchial levator muscle, and the dorsal fork traveled along be- 

 hind the same muscle. 



The final dorsal termination of the second, third and fourth 

 branchial lymphatic trunks are so different in these three dis- 

 sections that a brief description should accompany each, al- 

 though a far better idea can be obtained by carefully comparing 

 Figs. I, 2 and 3. In Fig. i the third branchial lymphatic 

 trunk unites with the fourth, behind the posterior border of the 

 third and fourth branchial levator muscles, and the common 

 trunk (^r.Z. 7^.(3) and (4)) continues dorsad behind the muscle 

 until the jugular is reached, when it receives from in front the 

 second branchial lymphatic trunk (dorsal fork of the second 

 branchial lymphatic trunk?), and the combined trunk (.r) after 

 crossing over the jugular empties into the cephalic trunk, a short 

 distance behind the hyo-opercularis sinus. In Fig. 2 the fourth 

 branchial lymphatic trunk unites with a rather large branch thai 

 comes up from the pharyngo-clavicularis muscle, and very 

 shortly is joined from the rear by the third branchial lymphatic 

 trunk. The course of this common trunk (^r.Z. 3^.(3) and (4)) is 

 then obliquely dorsad, following along the inner surface of the 

 second branchial levator muscle ; it soon collects the dorsal fork 

 of the second branchial lymphatic trunk, and the combined trunk 

 thus formed (x), discharges itself mesad of the hyo-opercularis 

 sinus in the ventral fork of the cephalic trunk. The remain- 

 ing ventral fork of the second branchial lymphatic trunk 

 (^r.Z. 7^.(2)) travels mesad of the first and second branchial 

 levator muscles, and likewise terminates in the ventral fork of 

 the cephalic trunk, a little below trunk (.r). In Fig. 3 the third 

 branchial lymphatic trunk makes a sharp curve on the outer 

 surface of the arch, where it receives a common trunk, formed 

 from the union of the fourth branchial trunk with a vessel com- 

 ing from the occipito-clavicularis muscle and the region behind 

 the fourth branchial arch. The dorsal fork of the second 

 branchial lymphatic trunk after traveling along the posterior 



