and Species 0/ Polyzonidas. 225 



and very little else was known in each case, to assign to the 

 North-American genera a position in the Platjdesmia and to 

 associate Dolistenus with SiplionopJiora in the subfamily 

 Dolistenia. Whether Octoglena^ Petaserpes, and Andro- 

 gnathus be really related to Platydesmus and to Pseudodesmus 

 remains to be shown. 



Family PolyzonidsB. 



Subfam. 1. Plattdesmini. 

 Maxillis secundi paris Juli gnathochilario similibus. 



1. Platydesmus. 



Capite oculis ornato ; numero segmentorum minore quam 

 septuaginta. 



2. Pseudodesmus. 



Oculis nullis ; numero segmentorum majore quam septua- 

 ginta. 



Subfam. 2. PoLTzomm. 



Gnathochilario in laminam antice acutam, simplicem, Juli 

 gnathochilario haud similem mutato. 



1, POLYZONIUM. 



Capite oculis ornato ; numero segmentorum minore quam 

 septuaginta. 



2. SiPHONOPHOEA. 



Oculis nullis ; numero segmentorum majore quam septua- 

 fi-inta. 



Note. — Since sending the above to press I have come across, 

 in the work of Antonio Berlese upon the Acari, Myriopoda, 

 and Pseudoscorpiones of Italy, a figure of the gnathoehilarium 

 of Dolistenus, which shows that, as regards the mouth-parts, 

 this genus is more nearly allied to Pseudodesmus than to 

 Siplionoijliora, and will therefore be classed in the subfamily 

 Platydesmini. 



The form of the mentum, the shape of the body-rings, and 

 the possession of more than one hundred segments are cha- 

 racters sufficient to separate Dolistenus from Pseudodesmus. 



