ON THE CHILOPODA OF NORTH AMERICA. 17 



S. fi i \ i, Sieger. — S. fulvo-aurantiaoa, polita; corpore antice attenuate ; capiteparvo; segmento cepha- 



lico subtriangulare, impunctato; antennis 1 lice longis, filiformibus, haud acumiuatis, sparse pilosis, 



articulis obconicis; mandibulis brevibus, crassis, singula dcnticulo modice magno conico; labio breve, 

 arjtice medio valde emarginato, impunctato; scutis interdum linea media ol una; pedibus modice 



longis, pilosis, gracilibus, cylindricis, utrinque 17, pari postremo (in marry; robusto, breve acuminato 

 articulis obconicis, (in femina?); sternis suturis stemo-episternalibus e( suleo mediano lato impressis. 

 S rigamiafulva, Sieger, Proc. Acad. \ it. Scien. vol. viii. p. 109. 



The color of this graceful little animal is an orange, approaching somewhat to 

 fulvous. The antennae are very thread-like; but the posterior feet, in our only speci- 

 men, are very thick, being more so in the middle than at either end. The median 

 linear depressions in the sterna are often dilated in their centre. The type of this 



species is in the Museum of the Academy. 



Specimen belonging to tin Smithsonian Institution. 



349 | 1 | South Illinois. | R. Kennicott. | Una 1 | • | 



S BIDENS, n. sp, — S. aurantiaca, venuste polita; segmento cepbalico triangulare, anticc truncato, sparse 

 late punctato, margine antico postico nonnihil latiore; antennis brevibus, filiformibus, articulis ob- 

 conicis; labio sparse late punctato, sulco obsoleto, margine antico denticulis duobus obsoletis obtusis 

 armato; mandibulis intus miuute unidenticulatis ; suturis scuto-episcutalibus nullis; pedibus utrinque 

 Tii, cylindricis, pans postremi coxis niagnis, foveis signatis; sternis suturis sterno-episternalibus et sulco 

 median impressis ; squama prcanali infra convexa. 



The coxae of the las! pair of feet are very large. Their inferior surface is convex, 

 and indented with from twenty to thirty small, round pits, irregularly arranged in rows. 

 The remainder of the feet are. in our specimen, slender. We presume that the ahove 

 character is persistent in both sexes, but cannot be certain on this point. There is a, 

 single specimen in the Museum of the Academy, labelled as having been found near 

 Philadelphia by Joseph Leidy,M.D. We have never met with it whilst collecting. 

 The length is about tin inch and a half. 



S. Whitei. — S. " capite aurantiaco, corpore flavo-virente. segmento cepbalico brevi subcordato, antennis 

 nudis, moniliformibus. labio levitcr longitudinaliter cristato, utrinque oblique sulcato, pedum paribus 

 74. Long. unc. 1 \." 

 phUus Whitei, Ncwp., Linn. Trans, xix. p. LJ'i ; Grervais, Apteres iv. p. 321. 

 "Eab. — In America Boreali." 

 Species niihi ignota. 



S. bidens \- closely allied to this species, but almost the only point of agreement is 

 the number of pairs of legs. Mr. Newport's description is, however, meagre, and we 

 have never seen a specimen entirely corresponding with it. 



G. attentates, Say, Journ. Acad. Xat. Sci. 1st series, vol. ii. p. 114. 



We have not been able to learn any thin- as to what species Mr. Say referred in 

 his description, which throws no light on the subject; possibly it belonged to the 

 genus Meeistocephalus. 



