chamberlin: chilopods from Mexico and west indies. 531 



LITHOBIOMORPHA. 



LITHOBIOIDEA, superfam. no v. 



Proposed to embrace the Lithobiidae sens, sir., Ethopolidae, fam. 

 nov. (Ethopolys, Bothropolys and allies), Watobiidae, and Gosibiidae, 

 fam. nov. (Gosibius, Arenobius and allies) in contrast with the Heni- 

 copoidea, superfam. nov. (the Henicopidae). 



GOSIBIIDAE, fam. nov. 



All but one or two species of the known lithobioid fauna of Mexico 

 belong to genera of this family, which ranges into the southern United 

 States, extending in California as far northward as Oroville and north- 

 eastward to Tennessee and North Carolina. 



Atethobius, gen. nov. 



Head without distinct lateral marginal breaks much as in Bothro- 

 polys. 



Antennae composed of numerous articles, numbering above forty. 



Eyes composed of seriate ocelli. 



Prosternal teeth 2 + 2. Spines ectal in position; stout and tooth 

 like. 



Posterior angles of the seventh, ninth, eleventh, and thirteenth 

 dorsal plates, strongly produced, these plates appearing deeply mesally 

 excavated posteriorly, processes broad and rounded. The four- 

 teenth dorsal plate greatly enlarged, being distinctly wider than any 

 of the more anterior plates and completely extending over and con- 

 cealing the reduced fifteenth plate and the anal coxae. 



Coxal pores uniseriate. 



Claw of female gonopods large, strictly entire. Spines stout, 

 conical. 



Tarsi of all legs biarticulate. None of posterior coxae armed either 

 laterally or dorsally. 



Anal legs with two claws, dorsal spines 0, 0, 3, 2, 0. Dorsal spines 



