100 THE CANADIAN ENTOMOLOGIST. 



bb. Claw of the anal legs armed wiih one spine. 



c. Claw of the penult legs armed with one spine. 



Spines of first legs i, 3, 2 ; of penult, i, 3, 3, i ; of anal, 

 I, 3, 2, I ; length, 8-1 1 mm . . . . Z, politiis McNeil. 



cc. Claw of penult legs armed with two spines. 



Spines of first legs i, 3, 1-2, 3, i ; of penult, i, 3, 3, 2 ; 

 of anal, i, 3, 2, o Z. niimius^ sp. no v. 



bbb. Claw of anal legs armed with two spines. 



c. Claw of penult legs armed with two spines. 



Prosternal teeth 2>'^?i\ articles of antennae 20 ; spines of 

 penult legs 1,3, 3, 2 ; of anal, i, 3, 2, i ; coxal 

 pores round, 3, 4, 5, 3 Z, bins, sp. rov. 



aaa. Posterior angles of none of the dorsal plates produced. (Metalitho- 

 bius aut.) 



b. Claw of anal legs unarmed. 



c. Claw of penult legs armed with two spines. 



d. Claw of gonopods of female entire. 



e. Articles of antennae 20-23 ; prosternal teeth 

 2 + 2 to 4 + 4. 



f. Spines of penult legs i, 3, 3, i ; of anal, 

 I, 3, 2, o; anal legs of male with 3rd 

 and 4th joints produced mesad into 

 conspicuous lobes, the corresponding 

 joints in female also usually bearing 

 lobes Z. hilabiatus Wood. 



ff. Spines of penult legs i, 3, 3, 2 ; of anal, 



^ ■:?)•< Z^ I ? 3^^ ^'^^ 4^^^ joints of anal 

 legs not thus produced into lobes, the 

 5th joint in some males with a small 

 keel at distal end 

 dorsad Z. jowensts Meinert. 



ee. Articles of antennae 24-29 ; ]"»rosternal teeth 

 5 + 5 to 6 + 6 Z. proridens Bollman. 



dd. Claw of gonopods of female tripartite. 



e. Length, 9-1 1 mm Z. pullus Bollman. 



ee. Length, 15 mm. or above. 



