POINTS 01' THE ANATOMY OF POLYXENUS LAGURTJS. 27 



On Some Points of the Anatomy of Polyxenus 



lagurus. 



By 



F. e. Heatbcote, m.A., 



Fellow of the Cambridge Philosophical Society. 



With Plate III. 



The following does not profess to be a complete account of 

 the anatomy of this interesting little Myriapod. In working 

 out the development of Julus terrestris, certain questions 

 occurred which led me to investigate the adult anatomy of 

 some other forms, amongst them of Polyxenus, and I con- 

 sidered that the following notes might be of interest to other 

 observers. I found it very difficult to obtain material, and 

 had it not been for the kindness of Dr. St. Remy, who was 

 also working at Myriapods, and who took great trouble to 

 procure a supply of Polyxenus for me, I must have delayed 

 the publication of these notes for a considerable time. This 

 form has been investigated by several naturalists, especially by 

 Fabre and Bode (2, 1).^ I have also availed myself of the 

 excellent work of Latzel (4). 



External Features. 



In comparing the body of Polyxenus with that of Julus, the 

 most striking peculiarity in Polyxenus is the composition of 

 the individual segments. Each body-ring, as described by 

 Bode, consists of a dorsal plate, two lateral plates, and two 



' The figures refer to the list of literature at the end of the paper. 



3 



