284 S- Vincent, 



II. The Suprarenal Bodies in Invertebrata. 



Leydig, [73] in a most interesting passage, discusses the possibility 

 of the existence in some Invertebrata of the equivalents of the 

 suprarenal bodies. He says: "Es sind in verschiedenen Wirbellosen 

 am Nervensystem Zellen beobachtet worden, die von den gewöhnlichen 

 Granglienkugeln differierten. So habe ich schon früher von Paludina 

 vivipara mitgeteilt, dass an den vegetativen Nerven 'eigentümliche 

 Zellen vorkommen, die vielleicht Ganglienkugeln eigener Art sind; sie 

 sind gelblich, haben im Innern verschiedene Bläschen und stehen in 

 keinem directen Zusammenhang mit den Nervenprimitivfasern'. Auch 

 an den Granglien von Pontobdella verrucosa machten sich besondere 

 Zellen mit gelbkörnigem Inhalt auffällig." He quotes also a description 

 of Meissner concerning similar cells in Mermis and concludes: "Meine 

 Meinung bezüglich dieser Zellen von unbekannter Bedeutung an Palu- 

 dina j Pontobdella, Mermis (und wahrscheinlich wird ein näheres Nach- 

 sehen die Zahl der Beispiele sehr vermehren) geht dahin, sie als 

 Analoga der Nebennieren vorläufig zu betrachten." 



I had long considered the possibility of the existence of suprarenal 

 bodies of some sort in the Invertebrata, but had not myself succeeded 

 in finding any organ or tissues which seemed likely to represent 

 them. But recent physiological researches have put it into our power 

 to test any organ to see if it be medullary suprarenal (Oliver and 

 Schäfer [S7], Swale Vincent [-Z5Ö]). Accordingly, I dissected out the 

 nervous system as completely as possible from about a dozen fair-sized 

 specimens of Paludina vivipara. The material (in which of course 

 was included the groups of cells described by Leydig) was then made 

 into a decoction by boiling for a short time with normal saline and 

 carefully filtering. This was then injected into the venous system of 

 a cat while a record of the blood-pressure was being taken. The 

 result was quite negative, there being not the slightest rise of the 

 blood-pressure. 



If these cells of Leydig represented any part of the suprarenal 

 capsules at all, this would be the medulla, since it is the medulla 

 which is found in Vertebrata to bear a close relationship to the 



