—62 — 



The Scolopendridae may be readily distinguished from all other 

 Chilopoda in the possession of either 21 or 23 pairs of legs. The body 

 segments being so similar the essential characters are drawn from the 

 head and its appendages, the first body segment (basilar segment), and 

 the last segment with its so-called anal legs ; other characters are drawn 

 from the spiracles, the armature of the femoral joints and of the tarsi; 

 sexual characters have never been used in classification. A vast amount 

 ol work must be done in studying the early stages of not only this family 

 but all other families of the Myriapoda before specific lines may be re- 

 garded as settled. 



The reported occurrence of a tropical genus in the Southern States 

 necessitates an enlargement of the synoptic table given in the first volume 

 of this journal. 5 



The genera may be distinguished as follows : 

 A. —With 23 pairs of legs, all 5 -7-jointed ; ocelli wanting ; antenna; 17-jointed. . . 



Scolopocryptops Newp. 



With 21 pairs of legs B 



B. —With nine pairs of simple: stigmata ' ; C 



With ten pairs of stigmata, which are inclosed in a deepened, wrinkled, gill- 



like integument ; antennae 17— 2l-jointed Branchiostoma Newp. 



C — Ocelli four each side ot head ; cephalic segment overlapping the first dorsal. . , 

 t Scolopendra L. 



< )celli inconspicuous or wanting D 



D. — Last dorsal scutum enlarged ; prosternal teeth present ; Iabrum one toothed. . 



Opisthemega Wood. 



Last dorsal scutum not larger than the others ; prosternal teeth wanting : 



labium 3 — 5-toothed Cryptops Leach. 



In the following enumeration of species those represented in the 

 National Museum are marked with an asterisk ; localities from whence 

 species are represented in the same collection are followed by a point of 

 exclamation. 



I. SCOLOPOCRYPTOPS Newp. 



Seven nominal species have been described which are here reduced 

 to three, and it is possible that two of these are separated by characters 

 that will not prove constant.- 



The species may be thus distinguished : 



A.— Anal legs (except the femoral joint) more or less densely pubescent; prosternal 

 teeth present lanatipes W I 



•"' The North American Myriapoda, Entomologies Americana, I, 141 — 151, 

 (1885). 



'• In the common Scolopeodra heros these stigmata appear as horizontal slit-like 

 openings above the legs on the 3rd, 5th, 8th, 10th, 12th, 14th, 16th, iSth and 20th 

 body segments. In Branchiostoma the 7th segment bears stigmata in addition to 

 those above named. 



