LYMPHATICS IN TAIL REGION, SCORP^NICHTHYS 35 



(p. 181) that the longitudinal neural trunk is absent, and in his 

 fig. 84 no longitudinal haemal trunk appears. With Lucius lucius, 

 Favaro noticed both profundus longitudinal trunks; the longitu- 

 dinal neural did not extend caudad far enough to empty into the 

 atrium of the caudal heart; while the longitudinal hsema] trunk is 

 well developed, and after anastomosing with the profundus por- 

 tions of the lateral trunks, the combined trunk emptied into the 

 atrium of the caudal heart. In Coricus rostratus (p. 208) there 

 is said to be no longitudinal hsemal trunk, but a longitudinal 

 neural trunk is represented as dividing and each fork anastomos- 

 ing with a profundus portion of a lateral trunk, the combined 

 trunks thus formed, fuse, and at the point of union, receive the 

 caudal trunk, and the common vessel thus formed does not empty 

 into the caudal heart, but terminates directly into the sinus 

 venosas of the caudal vein. In the eel, Anguilla, Favaro states 

 (pp. 157-8) that the longitudinal hsemal trunk is the only profun- 

 dus lymphatic trunk observed, and it is said to terminate directly 

 in the cephalic end of the atrium of the caudal heart. 



SUMMARY AND GENERAL CONSIDERATIONS 



In the tail region of the Cottids, Scorpsenichthys marmoratus 

 and Clinocottus analis there is a distinct system of longitudinal 

 canals, which has no counterpart in the arterial system. It con- 

 sists of four longitudinal subcutaneous trunks and two longitudi- 

 nal profundus trunks. None of these terminate behind the last 

 vertebra in caudal sinuses, which empty into the caudal vein, as 

 is the case with many fishes. In fact, so far as could be determined 

 there is no direct communication of the lymphatics with the cau- 

 dal vein or with the arterioles in the periphery. It should be 

 noted, however, that in four places, namely, on either side of 

 the last vertebra and at the base of the tail this system comes into 

 close touch with the two forks of the caudal vein, and in one sec- 

 tion of Clinocottus the thin wall separating the profundus por- 

 tion of the lateral trunk and the right fork of the caudal vein was 

 torn in such a manner as to give the appearance of the lymphatic 

 trunk empting into the vein and the orifice being guarded by 



