1911] Nervous System of Corydalis 231 



side of the longitudinal fibers which are continued out into the 

 connectives. 



Above this as the cells disappear and we come clearly into 

 the region where there are only longitudinal tracts, these may 

 be followed and they are indistinguishable from other fibers of 

 the connectives. The reason why the lateral tracts could be 

 told from the longitudinal for such a distance was because they 

 seemed denser and stained more deeply. The fibers in the 

 cephalic connectives have about the same arrangement as the 

 caudal ones. 



In other abdominal ganglia, ventral and lateral groups of 

 nerve cells were more clearly seen contributing to the com- 

 missures and the central tracts. Some of the fibers of the 

 lateral trunks end in the central portion of the ganglion, prob- 

 ably in cells. 



The tract of the lateral trunk needs a word of additional 

 comment. In preparations made by a method that removes 

 the cells and all but the denser fibers so that little more than a 

 skeleton of the fibrous framework is left, it is found that a 

 transverse portion connecting the two sides of the ganglion is 

 much denser than other parts of the fibrous mass and under the 

 highest powers of the microscope, this seems to be very finely 

 granular as well as fibrous and is continuous from side to side 

 between the nerve trunks. This same fine granular substance 

 with fibrils in it was traced up into the connectives a short dis- 

 tance, and as many fibers are seen to end in this region it may 

 be due to a dense grouping of their endings that there is a 

 deeper color at such a place. Similar substances to this only 

 in more isolated portions is found in other parts of the ganglion 

 and in other nerve centers. In specimens stained with ordinary 

 hematoxylin there is no differentiation between this substance 

 and the general fibrillar mass. 



The eighth abdominal ganglion is similar to the others 

 except that the connective fibers begin within the ganglion and 

 there are more commissures developed. The first lateral 

 branch can be easily traced out into the connective on the out- 

 side, fibers also deeper in go on up the connective, while still 

 others enter the ganglion and are distributed to all parts of one 

 side and probably also across to some extent, as there are 

 numerous cross connections, by means of at least three of four 

 well marked commissures, besides irregular fibers. Other 



