26 WILLIAM F. ALLEN 



as passing along the side of the last vertebrae, where each collected 

 a lateral and a longitudinal haemal trunk; and one or the other of 

 them, the dorsal subcutaneous trunk. In the tail region of Lep- 

 isosteus the dorsal and ventral subcutaneous trunks are enormous 

 canals, and contrary to the Selachians they do not divide upon 

 reaching the dorsal and anal fins, but pass directly through their 

 basal canals and collect branches from their rays. 



In the teleosts Hyrtl and Vogt noted two caudal hearts behind 

 the last vertebra in Lucius, Leuciscus, and Salmo, which termi- . 

 nated in the caudal vein. Since the dorsal and ventral lymphatic 

 t runks were not described they must have been overlooked Trois 

 described a dorsal and a ventral lymphatic trunk in Lophius (pp. 

 (3_8)^ Uranoscopus (pp. 23-24), and in the Pleuronectida? (pp. 

 40-41). In Lophius and Uranoscopus these trunks were said to 

 trifurcate in the region of the dorsal and the anal fins, one trunk 

 passing through the basal canals of the fins and the other two to 

 either side, and the median trunk was represented as collecting 

 two ray vessels from each ray. Nothing of especial interest 

 was said concerning the caudal ending of these trunks, but in 

 Uranoscopus, according to fig. 4, the dorsal and ventral lymphatic 

 trunks are continued to the tail, where they apparently fuse with 

 the longitudinal neural and haemal lymphatic trunks. They com- 

 nmnicate superficially with the lateral trunk through the inter- 

 muscular vessels, and deeply with the longitudinal neural and 

 haemal trunks through the neural and haemal vessels. In all 

 these fish Trois portrayed the superficial lymphatic trunks to be 

 well developed posteriorly. Sappey (p. 471, and pi. xi, fig. 5, and 

 pi. xii,fig. 2) found a somewhat similar arrangement of the dorsal 

 and ventral lymphatic trunks of the carp and pike to that of 

 Trois for Lophius and Uranoscopus; except that the dorsal and 

 ventral trunks in the caudal region are less important canals, for 

 they did not extend clear to the tail. In Pleuronectes the dorsal 

 and ventral lymphatic trunks were portrayed by Sappey (pp. 

 50 and p. xii, fig. 4) as being continued through the basal canal 

 of the caudal fin, where they anastomosed and thus formed an 

 elliptical trunk about the body, which emptied dorso-cephalad 

 in the jugular and ventro-cephalad in the ductus of Cuvier. 



