224 Annals Entomological Society of America [Vol. IV, 



nerve fibers of the connectives when stained in a mass form 

 deep lines apparently running straight through the center of 

 the ganglia, these longitudinal bundles of nerve fibers seem to 

 be a little broader before entering and after leaving the central 

 mass. The nerve trunks in deeply stained specimens send 

 masses of fibers into the ganglia and in the case of most of the 

 fibers, the region where they seem to terminate is in the central 

 part of each ganglion. This is true of all the ventral fibers 

 and of most of those from the lateral trunk, but a few of the 

 latter, and some fibers from the second branch of the lateral, 

 run up into the edge of the ganglion only, and then straight up 

 the connective to the next ganglion above. In the case of the 

 eighth adbominal the four nerve trunks enter the fibrous central 

 mass from below, those most medially placed seem to be con- 

 tinued up through to the connectives and to be largely contin- 

 uous with them in deeply stained specimens, while the more 

 lateral trunks are lost sight of as they enter the central portion 

 of the ganglion, although some of the fibers from the more 

 laterally placed nerve trunks pass through the edge of the 

 ganglion without communication with its cells and pass up 

 the outer side of the connectives on either side to the next 

 ganglion above. There are then two masses of fibers entering 

 each center but the last, those of the connectives and those of 

 the nerve trunks. I will first take up those of the connectives. 

 Beginning with the seventh abdominal ganglion great masses 

 of fibers enter, and it is possible to distinguish; (a) Fibers which 

 run straight through without terminating. There seem to be 

 great numbers of these, but this is due in part to the fact that 

 when fibers do terminate in a ganglion they end at various 

 levels. These fibers can however individually in a number of 

 cases be traced through a ganglion without endings of any sort 

 within it, just how far some of these may run without termina- 

 tion is a question, but there was no difficulty in tracing them 

 through three ganglia and there is no reason to doubt that 

 they may be longer than this. Those most easily followed 

 were usually of larger size than the rest, (b) Fibers from below, 

 terminating within the ganglion. Of these there are several 

 sorts: (1) Those ending in the lower part of the "punktsub- 

 stanz" on the same side. (2) Those ending on the same side 

 above. (3) Those crossing over towards the opposite side 

 from below. (4) Those crossing over to the opposite side above. 



