310 n. M. BERNARD. 



kept in place witliin sucli meslies was a puzzle to me which 

 became still more perplexing when^ as not seldom happens, the 

 syncytial strands are so scanty that very few can be traced 

 at all, even with the best microscope. 



But before coming to this point, let me say that the 

 a priori improbability of a tissue with simple nuclei not, as 

 a rule, in direct contact with any cytoplasm, led me to test 

 the observation again and again in every possible way. I 

 have studied small slices of nuclei cut tangentially and 

 isolated in the sections with the highest microscopic powers 

 (cf. fig. 4). I can see nothing in such cases but the 

 frequently angular reticulum of the nucleus. Indeed, I have 

 quite convinced myself that, except for the few that become 

 apparently accidentally involved in the " Miiller's fibres" 

 and the spindle-shaped cells at the rim of young retinas, the 

 membranes and strands of the syncytial framework are not 

 normally in contact with the nuclei, but run between them, or 

 if they are in contact, it is of the nature of an accident and 

 due to crowding.^ 



This discovery will certainly help to settle certain long- 

 standing differences of observation. The nucleus has always 

 hitherto been thought of as necessarily embedded within a 

 mass of cytoplasm, and such nuclei only have been studied. 

 Any direct connections between the nucleus and its surround- 

 ing tissues, if any such connections exist, have been obscured 

 by the enveloping mass of cytoplasm, and the prevailing 

 doctrine is that whatever connections it may have with its 

 surroundings are only indirect, namely, through the inter- 

 mediary of its own cytoplasm. But now Ave have a tissue, 

 viz. the retina, in which the majority of the nuclei have no 

 masses of cytoplasm obscuring tliem, and can be studied by 

 themselves, and their connections, if they have any, can be 



> In very younc; eyes the nuclei may be packed so tightly togel.her as to be 

 polyf;onal (fig. 14); in sucli cases they must, of course, be in contact with 

 any syncytial framework whicli happens to be present. As the eye grows 

 older tlic nuch'i move apart from one another, and strands of the supporting 

 framework appear irregularly between them. 



