THE SUPRARENAL GLANDS. 219 



organ. I have, hitherto, investigated this only in an embryo 

 of three months, in which, like Ecker, I found the cortex 

 whitish, the medulla whitish-red, and both constituted of cells 

 and fibres. The cells measured 0*012 — 0-02"', had well 

 marked, in part colossal nuclei, with distinct nucleoli, and in the 

 cortical part also fatty molecules. Of the nerves at that period 

 I saw nothing. In a newly-born Rabbit, Ecker observed no 

 appearance of follicles, whilst in a foetal Calf, T-6" long, he 

 found them very distinct, but small (0'05 — 0*15 mm ). 



As regards the functions of the suprarenal glands, in the ab- 

 sence of all physiological indications, and so long as the course of 

 the nerves in them is not much more accurately known, only very 

 general observations can at present be offered. / consider the 

 cortical and medullary substances as physiologically distinct. 

 The former may, provisionally, be placed with the so-termed 

 " blood-vascular glands," and a relation to secretion assigned 

 to it ; whilst the latter, on account of its extremely abundant 

 supply of nerves, must be regarded as an apparatus appertaining 

 to the nervous system, in which the cellular elements and the 

 nervous plexus either exert the same reciprocal action as they 

 do in the grey nerve- substance, or stand in a relation as yet 

 wholly unascertained, towards each other. (For a more detailed 

 account vid. Mikros. Anat. II. 2. zw. Halfte.) 1 



1 [The former and more recent researches of Leydig (' Anatomisch-histologische 

 Unters. iib. Fische u. Reptilien,' 1853), appear satisfactorily to show the identity of 

 the suprarenal glands of the Mammalia, with the yellow, vascular bodies seated, 

 either on the kidney itself and its emulgent veins, or at a greater distance from those 

 glands, on the veins near the epididymis or ovaries, or upon the sympathetic nerve. 

 The study of these more simple forms has also thrown very considerable light upon 

 the structure and true import of the more complicated organ in the Mammalia. In 

 the Salamander, the ganglia of the sympathetic have a very remarkable structure, 

 and contain cellular elements of two very distinct kinds. Each ganglion has a tunic 

 of connective tissue which sends septa into the interior, which is thus divided into 

 distinct and occasionally, perfectly separate compartments. The cells of both kinds 

 are enclosed in these compartments, and are never intermixed in one and the same. 

 In some of the compartments, or as they might almost be termed, vesicles, the cells 

 are large, clear, and finely granular, with a vesicular nucleus and very transparent 

 nucleolus. From some of these cells, nerve-fibres are distinctly seen to proceed, and 

 they would appear to be of the bipolar kind of ganglion- or nerve-cells. The other 

 kind of cells, contained in perfectly distinct compartments, are much smaller and 

 their contents of a peculiar dirty yellow colour, owing to which the perfectly trans- 

 parent nucleus is rendered very distinct. 



These two kinds of cells occur in very variable proportions in different ganglia. 



