DISTRIBUTION OF LYMPHATICS IN SCORP.-EMCIITIIYS 69 



except that no connection is noted with the venous system. 

 According to Sappey (25) there are no cephalic sinuses in the 

 carp or the pike. He states that both the lateral and myelonal 

 or superior longitudinal spinal lymphatic trunks empty directly 

 into the jugular, and with the Pleuronectidie the inferior spinal 

 or longitudinal hcemal trunk likewise terminates in the jugular, 

 while the ventral trunk empties directly into the ductus Cuvieri. 

 No other vessels were mentioned from the head region, doubt- 

 less for the reasons given above. Hopkins represents the lat- 

 eral lymphatic trunk of Aiuia (8, p. 371) as passing under the 

 clavicle and opening into a cephalic sinus at the base of the 

 cranium. This sinus is described as receiving the pericardial 

 sinus from below ; its opening into the jugular is said to be 

 about 1 cm. cephalad and a little ventrad of the dorsal end of 

 the clavicle, and the orifice is guarded by a valve opening into 

 the vein. 



Possibly it might simplify matters somewhat to classify the 

 cephalic sinuses and their connections described in the previous 

 paragraph under 5 different heads. Firsts in Acifienscr, Cy- 

 ■prinus Leaciscus, Fsox, etc., the lateral trunk after passing 

 under the pectoral arch follows the ramus lateralis vagi to the 

 base of the skull, and there expands into a cephalic sinus that 

 empties into the jugular. Second, with Lofhius, the salmon, 

 trout, ray, and shark the lateral trunk immediately after pass- 

 ing under the shoulder-girdle discharges itself in a cervical or 

 cephalic sinus that empties into the precava, and which accord- 

 ing to Vogt in the salmon receives other trunks from the face 

 and the branchial arches. Third, midway between these two 

 extremes comes Aw/a with a lateral trunk which after passing 

 under the clavicle terminates in a cephalic sinus, that also re- 

 ceives the pericardial sinus, and which ultimately empties into 

 the jugular instead of the precava. Fourth, Perca, Tinea, 

 and Cottus are vaguely described as having two communica- 

 tions with the venous system ; probably the jugular and pre- 

 cava connections are the ones referred to. Fifth, with the 

 carp, pike and flatfish there are said to be no cephalic sinuses, 

 the main lymphatic trunks emptying directly into the jugular 

 and precava. 



