OF THE VERTEBRATE OVARY. 593 



hesitation in identifying it with the segmental cords (segwent- 

 alstrdnge] discovered by Braun in Reptilia, and described at 

 length in his valuable memoir on their urogenital system *. Ac- 

 cording to Braun the segmental cords in Reptilia are buds from 

 the outer walls of the Malpighian bodies. The bud from each 

 Malpighian body grows into the genital ridge before the period 

 of sexual differentiation, and sends out processes backwards 

 and forwards, which unite with the buds from the other Mal- 

 pighian bodies. There is thus formed a kind of trabecular 

 work of tissue in the stroma of the ovary, which in the Lacertilia 

 comes into connection with the germinal epithelium in both 

 sexes, but in Ophidia in the male only. In the female, in all 

 cases, it gradually atrophies and finally vanishes, but in the 

 male there pass into it the primitive ova, and it eventually forms, 

 with the enclosed primitive ova, the tubuli seminiferi. From 

 my own observations in Reptilia I can fully confirm Braun's 

 statements as to the entrance of the primitive ova into this 

 tissue in the male, and the conversion of it into the tubuli 

 seminiferi. The chief difference between Reptilia and Mammalia, 

 in reference to this tissue, appears to be that in Mammalia 

 it arises only from a few of the Malpighian bodies at the 

 anterior extremity of the ovary, but in Reptilia from all the 

 Malpighian bodies adjoining the genital ridge. More extended 

 observations on Mammalia will perhaps shew that even this 

 difference does not hold good. 



It is hardly to be supposed that this tissue, which is so con- 

 spicuous in all young ovaries, has not been noticed before ; but 

 the notices of it are not so numerous as I should have antici- 

 pated. His 2 states that the parenchyma of the "sexual glands 

 undoubtedly arises from the Wolffian canals, and adds that 

 while the cortical layer (Hulle) represents the earlier covering 

 of a part of the Wolffian body, the stroma of the hilus, with 

 its vessels, arises from a Malpighian body. In spite of these 

 statements of His, I still doubt very much whether he has 

 really observed either the tissue I allude to or its mode of 

 development. In any case he gives no recognisable description 

 or figure of it. 



1 Arbeitcn a. d. Zool.-zoot. Tnstitiit Wurzburg, Bd. iv. 

 a Archivf. mikros. Anat. Vol. I. p. 160. 



