. Anatomischer Anzeiger. Anatomy, Comparative; Anatomy, Comparative. 195 W henever one of these niacro-nerves is met with on the one side, there is almost invariably a similar, not always identical, one on the opposite side of the body. It was stated that the macro-ganglion cells or their (naked) axis cylinders appear to strive towards the tips of the myotomes: this is the rule, as will presently be evident. In some embryos, but not by any means in all, another interesting and hitherto unheard of phenomenon in Vertebrate embryology is noticeable. An embryo with 83 somites (3 less than that of
. Anatomischer Anzeiger. Anatomy, Comparative; Anatomy, Comparative. 195 W henever one of these niacro-nerves is met with on the one side, there is almost invariably a similar, not always identical, one on the opposite side of the body. It was stated that the macro-ganglion cells or their (naked) axis cylinders appear to strive towards the tips of the myotomes: this is the rule, as will presently be evident. In some embryos, but not by any means in all, another interesting and hitherto unheard of phenomenon in Vertebrate embryology is noticeable. An embryo with 83 somites (3 less than that of fig. 1) illustrates this in a remarkable fashion. A combination drawing of several sections is reproduced in fig. 2. Two nerves (s. e. n.) with applied nerve-form ing nuclei, are seen pro- ceeding from almost the dorsal margin of the cord, one on each side, arching over the myotomes, and running downwards to- wards the haemal aspect of the body, in their course lying just under the epiblast and to the outer side of the myo- tome. A mode of termi- nation , otherwise than as shown in the figure, has not yet been deter- mined either in this or in any other case. If these subepiblastic nerves are met with in any embryo, they occur in numbers, and in this parti- cular series of sections very many such nerves are present. From what will shortly be described, I am quite prepared for the discovery that ganglion cells or, (what is much the same thing) nerve-forming cells may be found to be given off from the epiblast in loco along the path of these sub-epiblastic nerves, but as yet a direct observation cannot be recorded. Regarding the question as to the application (contact theory) of nerve fibres and ganglion cells, as opposed to fusion, about which much has of late been written A) it is of interest to find — and an 1) Vide inter alia Retzius, Zur Kenutnis des Nervensystems der Crustaceen, Leipzig Fig. 2. Transverse section of the trunk of a R. batis of 9 Please note tha
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