OP THE CONAEIO-HTPOPHTSIAL TEACT. 133 



To this appeal, Dr. Sapolini, whose treatise issues from a 

 Brussels press, may reasonably look for an affirmative response 

 from the accomplished Professor of Liege. M. Ed. Van Bene- 

 den*, referring to the body in Tunicaries (Savigny's " tubercle," 

 Hancock's and TJssow's " olfactory organ "), which is homologized 

 by.M. Julinf with the "pituitary gland" of Vertebrates, com- 

 pares it to the kidney, and holds that by a communication with the 

 " peribranchial cavity " of the Ascidian it discharges its urinary 

 excretion therein. 



The researches of which I proceed to communicate results have 

 been conducted with a diflferent aim, which has led me to trace 

 both the pineal and pituitary bodies, their appendages and con- 

 nections, or what I have termed the " conario-hypophysial tract," 

 from Man downward, until, in Ampliioxus, where the cerebral ex- 

 pansion of the myelencephalon is too feebly indicated, the horao- 

 logue of any part of the tract in question has baffled my quest — 

 unless the pore leading to the cavity in such expansion may be in 

 relation thereto. 



In the Mammalian series I have to observe that, in the lower 

 and smaller members, as the brain loses in relative size and com- 

 plexity, the pineal or conarial and pituitary or hypophysial bodies 

 and connections show a relatively larger size, with a less paren- 

 chymatous and a less interrupted tubular structure than in the 

 human brain. In the lower, if not lowest, forms of the feathered 

 class I have noted a character of the basisphenoid which seemed 

 to me to bear upon the present topic : it is a median longitu- 

 dinal groove leading to a foramen opening into the seat of the 

 pituitary body J. 



But leaving here the class of Birds in the present summary, 

 the projDortions of the conario-hypophysial tract to the cerebral 

 hemispheres in Eeptiles become greater, and a vascular chord is 

 continued upward from the hollow "pineal" part of the tract, 

 beyond the cleft between the pros- and mesencephalon, to a con- 



* ArchiTesde Biologie, 8to, 1881, torn. ii. fascicule ii. p. 230. 



t Ibid, fascicule i. p. 59 et seq. (I may remark that, regarding the cylin- 

 droid shape as well as position of the neural centre in some Ascidians, I hare 

 viewed it as the homologue of the same part in Amphioxus, and the co-extensive 

 body beneath as that of the notochord.) 



I See ' Memoirs on the Wingless Birds of New Zealand,' 4to, 1878 : Dinornis 

 elephantcypus, pi. IxxtI. fig. 4, 5; i>. crassus, pi. Irxvii. fig. 3, 5 ; J9. inge7is, 

 pi. Ixxxii. fig. 3, 5 ; B. gravis, pi. Ixxxi. fig. 4,— in which the foramen, not 

 eustachian i unusually and significantly large. 



