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ALLEN 



work ; so that each branchial arch would have a minute capil- 

 lary network overlying and being connected with a more 

 profundus and coarser network. Whether this outer capil- 

 lary network was also in communication with the branchial 

 arch arteries I am unable to state, any more than to say that 

 no connections were found. A large number of small vessels 

 were received from the gillrakers, the common arrangement 

 being that two minute branches followed along the opposite 

 surfaces of two neighboring gillrakers, collecting a minute 

 network (Fig. 17, G.R.L.IV.) found in the membrane joining 

 the two, and uniting at the bases of the gillrakers to form a 

 slender twig, which terminates in that porion of the branchial 

 arch lymphatic network, overlying the efferent branchial artery 

 (Fig. 17, Br.A.L.N.). 



In the specimen from which Fig. 17 was drawn the arterial 

 system was first filled with a blue mass, and afterward the sub- 

 cutaneous system was injected with the yellow from the cephalic 

 trunk. In certain areas, the minute capillary network found 

 in the outer membrane covering a branchial arch was colored 

 yellow and in other regions blue ; similar colored areas were 

 also found in the more profundus network, and in the superfi- 

 cial network of the branchial filaments. Other places also could 

 be found in the more profundus network of the arch and the 

 superficial network of the filaments, which were colored green, 

 showing that the two injecting masses had fused. It does not, 

 however, necessarily follow from the above, that these capillaries 

 are in connection with arterial twigs. For in almost every case 

 when the blood vessels were first injected, the cephalic trunk, 

 the superficial network of the filaments, and the profundus net- 

 work of the arch were found to be filled ; doubtless through 

 either the connection of the jugular with the cephalic sinus or 

 the inferior jugular with the branchial lymphatic trunks, or 

 through both. Since the profundus network of a branchial arch 

 was found to be in communication with the minute superficial 

 network, it is natural to expect that the mass found its way into 

 this network after this manner, rather than through hypothetical 

 arterial connections, which I have never been able to find, either 

 from dissection or a microscopical examination ; and upon inject- 



