22 



ON THE CHILOPODA OF NORTH AMERICA. 



S. viridis, Say. — S. viridi-brunnea; segmento cephalico late ovato, sparse leviter punetato ; pedibus flavis ; 

 antennis 23 articulatis, plerumque haud pubescentibus ; dentibus labialibus 8, duobus intiinis utrin- 

 que arete coadunatis, externo aeuto, sejuncto ; lauiinis dentalibus elongatis ; pedibus prostremis sub- 

 cylindricis, rnodice robustis; articulo basali tibiali longiore, supra subconvexo, margine haud elevato, 

 intus 2 — 5 spinis, subtus 7 — 12 spinis in serie vel triplici vel quadruplici dispositis, processu angulari 

 1 — 2 spinis; appendicibus analibus lateralibus profunde densequo punctatis, iuterduni elongatis, sin- 

 gula spinis apicalibus 2 — 5, et interdum altero marginale armata. 



S. viridis, Say, Proc. A. N. S. 1821, p. 110 ; (Euvr. Entom. Ed. Lequien t. i. p. 23. 



S. punctiventris, Newp., Ann. and Mag. Nat. Hist. xiii. p. 100; Linn. Trans, six. p. 386; Catal. Brit. 

 Mus. Myriap. p. 33. 



S. punctiventris, P. Gervais, Apteres t. iv. p. 277. 



S. viridis, P. Gervais, Apteres t. iv. p. 277 ; et Tabl. des Myriap. (Exp. Amer. du Sud, part, sept.) p. 30. 



S.parva, Wood, Proc. A. N. S. 1801, p. 10. 



The antennas are generally, but not invariably, without pubescence. The first seg- 

 ment of the body is the smallest, the third the next. The sutures between the true 

 sterna and episterna are well marked, those between scuta and episcuta barely trace- 

 able. The cephalic segment is slightly depressed. The dental lamina have their 

 margins rounded in some specimens. The scuta are frequently bordered with very 

 dark green posteriorly. The dorsum in some individuals has a dark central stripe, 

 vanishing posteriorly. This is, without doubt, the species intended to be indicated 

 by Mr. Say, although his description is exceedingly indefinite and scarcely agreeing 

 with the facts. "We have, however, seen one specimen with its posterior feet tipped 

 with blue, and another in which the posterior margination was yellowish. Neither 

 have we any doubt in referring Mr. Newport's S. "punctiventris to this species, although 

 the number and arrangement of the spines on the posterior feet differ somewhat from 

 those given by that author. One specimen (No. 329) approximates to his description. 

 Besides the specimens of the Smithsonian Museum, we have the types of S. 2>ci>'va in 

 the collection of the Academy, brought from the mountains of Georgia by Dr. Le Conte. 



Table showing variations in specific characters. 



: The labial teeth in this specimen are very small and much coadnate. 



