DISTRIBUTION OF LYMPHATICS IN SCORPvENICHTHYS 55 



running along at the base of the fins between the great lateral, 

 superficial, and profundus dorsal fin muscles are evidently the 

 main stems, and might be designated as the lateral dorsal lym- 

 phatic trunks (Figs. I and 4, D.L. V.) ; while the third or 

 median dorsal lymphatic trunk (Figs. 1 and 4, D.L. V. w ) 

 simply passes through the basal canal of the rays and collects 

 the dorsal fin lymphatic vessels. Numerous transverse inter- 

 linking vessels were noticed between the median dorsal and 

 the 2 lateral dorsal lymphatic trunks, and the dorsal Jin lym- 

 phatic vessels (Figs. 1 and 4, D.F.L. V.) were merely small 

 branches of the median lymphatic trunk, that followed along 

 the cephalic and caudal surfaces of each spine and ray and col- 

 lected the network from the fin membrane. Some variation, 

 however, is shown in the anterior region of the first dorsal, 

 where there is but one dorsal fin lymphatic vessel between the 

 first and second, and between the second and third spines, both 

 of which empty directly into the lateral dorsal trunks. In addi- 

 tion to receiving the dorsal fin vessels the median dorsal lym- 

 phatic trunk collects numerous small branches from the super- 

 ficial or extrinsic dorsal fin muscles (Fig. 1). Anteriorly these 

 2 lateral dorsal lymphatic trunks do not terminate directly into 

 cephalic sinus as described by Hopkins for Amia, but through- 

 out their entire course communicate with the lateral lymphatic 

 trunk through the intermuscular or transverse vessels, and with 

 the myelonal or longitudinal spinal lymphatic trunk through the 

 neural or interspinal vessels (Fig. 4, Neu.L. V.). The most ce- 

 phalic neural or interspinal vessel (Figs. 4 and 5, JVeu.L. V. w ) 

 does not empty into the myelonal trunk, but follows along be- 

 hind the skull and terminates in the cranial lymphatic trunk. 



Ventral lymphatic trunk and lymphatics of the ventral fins 

 (Figs. 1, 2, 3, 4, 6, 9 and 10, l V.L.V.). — According to 

 Milne-Edwards (16, p. 473) this vessel has been described by 

 Monro (14) and Hewson (5) in Gadus, and as was the case with 

 the dorsal trunk this canal seems to have been overlooked by 

 Hyrtl and Vogt, although the former states that a ventral fin 

 sinus is filled from a good injection of the lateral trunk. Stan- 

 nius (24, p. 253) describes this vessel as unpaired, running 



1 Figs. 7 to 10 are text-figs, on pp. 73, 74, 76 and 77. 



