THE PINEAL BODY 



129 



roof. This Beraneck 23 designated in 1892 as the noyau parietal. 

 The prominence thus described can be nothing else than the 

 closely set ganglia habenulae of the interbrain as shown by 

 Studnicka 384 in 1893 in Lacerta, by Klinckowstroem 209 in 1894 

 in Iguana, and by Leydig 239 in 1896 in Lacena. The parietal 

 nerve is made up of fine fibrils; it has a perineurium, a connec- 



* ; 



Fig. 67 The pineal eye of Varanus giganteus, according to Spencer, 1886. 

 Pa., parapineal organ; Npar., parapineai nerve; Bl., blood vessel. 



tive tissue, and glial sheaths. In Iguana it degenerates and 

 disappears in the adults, according to Klinckowstroem ('94). 20<J 

 In some cases Spencer 366 found the parietal nerve divided into 

 two or three strands, for example, in Lacerta ocellata and 

 Varanus gigameus. A similar splitting was found by Studnicka 384 

 in 1893 in Petromyzon. Klinckowstroem 209 in Iguana recognized 

 a second parietal nerve which arose from the left habenular 



MEMOIR NO. 9 



