. Anatomischer Anzeiger. Anatomy, Comparative; Anatomy, Comparative. 199 were not known long ago, than that -there should be any particular difficulty about them. Given the presence of ganglionic elements in the myotomes, one would naturally enquire what function they fulfilled, and how they got there. A motor function might almost be assumed from the position; but when the point may be solved by diligent observation, any assumption is out of place. The motor function is rendered certain by the following circum- stance. In later stages, i. e. in embryos of 40—45 mm. in length these ganglion ce
. Anatomischer Anzeiger. Anatomy, Comparative; Anatomy, Comparative. 199 were not known long ago, than that -there should be any particular difficulty about them. Given the presence of ganglionic elements in the myotomes, one would naturally enquire what function they fulfilled, and how they got there. A motor function might almost be assumed from the position; but when the point may be solved by diligent observation, any assumption is out of place. The motor function is rendered certain by the following circum- stance. In later stages, i. e. in embryos of 40—45 mm. in length these ganglion cells lie embedded in a mass of muscle substance. Actual instances of this will shortly be described, and evidence adduced for the motorial nature of all the transient nerve fibrils to the myotomes. How came the ganglion cells into the latter? In dealing with the subject matter of this paper I have kept as free as possible from bias, and have held myself prepared for any eventuality. All stages of the wandering of macro-ganglion cells to the myotome were to be found; but it was not so easy to meet with cases in which the ganglion cell could be seen forcing its way into this structure. This can indeed be proved to take place in many instances; but, looking carefully over the sections of younger embryos, other factors were noticeable. • The phenomenon of fig. 5 was remarked in several speci- mens of 22 mm. and upwards; and therefore further light on the matter was to be expected from the examination of slightly younger embryos. In one of 20—21 mm. in length the appearances depicted in fig. 6 were detected. This, again, is not an isolated case. When Fig. 6. Transverse section R. batis of 21 mm. of a. it first met my eye, it reminded me in a striking manner of what I had found to be the mode of origin of the egg-cells in M y z os tom a *)• 1) These results have not yet been Please note that these images are extracted from scanned page images that may have been dig
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