18 



B. H. BUXTON 



Palpigrades 



Koenenia, the coxal gland of which has been shown to be 

 closely related to that of the Solifugae, also shows a very simi- 

 lar arrangement of the ganglia. In the suboesophageal ganglion 

 there are five swellings on either side, one for each con-esponding 

 appendage, and from the posterior end of the ganglion a nerve 

 cord passes to the abdomen, in the anterior part of which there 



Diagram 5 Evansecent abdominal ganglia of Cliilobrachys. Five ganglia 

 on either side of the abdomen, the first three of which are connected by a nerve 

 cord running through the pedicle from the suboesophageal ganglion. Ent, 

 intestine. 



are tlii'ee distinct ganglionic swellings, beyond which the nerve 

 cord can not be traced. These three ganglionic swellings in the 

 genital region appear to correspond to the abdominal ganglion 

 of the Solifugae, in which they have become concentrated into 

 a single mass (diagram 6, fig. 2) . 



Note on the segmentation of the arachnids. To return to group 

 I, we find in each case that there are eighteen ganglia, and the 

 question naturally arises — to what extent do these ganglia 

 represent segments? 



