162 bulletin: museum of comparative zoology. 



439. Dimerogonus perkinsi Silvestri. 

 Fauna Hawaiiensis, 1904, 3, p. 337, pi. 12, fig. 57-12.1 

 Locality. — Hawaiian Islands: Maui: Haleakala.^ 



440. Dimerogonus koebelei Silvestri. 

 Fauna Hawaiiensis, 1904, 3, p. 338, pi. 12, fig. 63-65.1 

 Locality. — Hawaiian Islands : Maui : Haleakala.^ 



Eumastigonus, gen. nov. 



Differs from Dimerogonus in having the first legs of the male with 

 strongly developed claws and otherwise also similar to the succeeding 

 pairs. Third joint of legs not spined. Posterior gonopods two- 

 jointed as in Dimerogonus. Anterior median plate well developed. 

 Anterior piece of first gonopods at distal end with a finger-like inner 

 process as in Dimerogonus and an outer lobe bearing a series of stout 

 spines or pectinae or not. 



Genotype. — E. kaorinus, sp. nov. 



441. Eumastigonus kaorinus, sp. nov. 



Type.— M. C. Z. 4,867. Paratype.— M. C. Z. 4,868. New 

 Zealand: Kaori Forest, near Swainson (W. M. Wheeler). 



The anterior median plate of the male gonopods broad; anterior 

 border broadly and deeply excavated; proximal end on each side 

 extended out across base of gonopod. Distomesal process of anterior 

 or coxal piece of first gonopods in ventral view a little enlarged distad, 

 rounded, slender; membranous lobe broad; pectinate lobe below level 

 of mesodistal process, the spines stout and blade-like, not reaching to 

 level of tip of mesodistal process; telopodite with a series of setae 

 across its distal end. Distal joint of posterior gonopods angled on 

 mesal side near middle of length, distal portion slender and acutely 

 pointed. 



Eyes transversely narrowly elliptic, each composed of numerous 

 ocelli in four or five long transverse series. Antennae short, scarcely 

 widening distad, but each joint separately, strongly clavate. A sul- 

 cus across vertex; frontal region evenly convex, smooth and shining. 



