266 E. A. BAUMGARTNER 



cords. In tracing such vacuolated cords one can always find 

 a place where the connective tissue is interrupted and the cords 

 are continuous with the nervous tissue. This tissue is reticular, 

 like that of the infundibular wall, but it is questionable whether 

 it can be considered as nerve fibers. 



Various investigators have described nerve fibers coming from 

 the infundibular outgrowth and entering the hypophysis. Sterzi 

 ('09) believed such to be the case in elasmobranchs, and Stendell 

 ('14) accepts this. Johnston ('01) was sure such was not the 

 case in fish; Dendy ('13) found only a sympathetic supply in 

 mammals; while Tilney ('13) states that many nerve fibers he 

 around and are imbedded in the pars tuberalis of the cat. 



Connective tissue and blood vessels 



In all reptiles the hypophysis is separated from the cranium 

 by a connective tissue layer. This is extremely thin in snakes. 

 Staderini called attention to the proximity of two muscle masses 

 at the sides of the hypophysis in Gongylus. These are found 

 also in Lacerta, as noted by Gisi ('07), and in Sceloporus. In 

 turtles two lateral muscle masses are also present, but they are 

 farther removed from the hypophysis. Pigment in the connec- 

 tive tissue surrounding the hypophysis is found only in lizards. 

 Gisi found pigment in Lacerta and noted its absence in turtles, 

 although described as being present by Stieda. 



Layers of connective tissue surrounding the various parts of 

 the hypophysis have been described. Although Tilney states 

 that connective tissue is not present in the hypophysis of snakes, 

 I find it in snakes as well as the other forms studied. In Scelopo- 

 rus at least, the pars intermedia and anterior lobe are not com- 

 pletely separated by connective tissue. There is relatively more 

 connective tissue in the pars tuberalis of turtles and alligators 

 than in the remainder of the hypophysis. 



The carotids border the sides of the hypophysis in all reptiles. 

 Only in alligators and turtles is an anastomosing branch between 

 them present. This is caudal to, or imbedded in, the caudal 

 wall of the hypophysis and, in turtles, first appears in 5 mm. 



