Sellards — Structure of Paleozoic Cockroaches. 213 



Art. XXVI. — A Study of the Structure of Paleozoic Cock- 

 roaches, with Descriptions of New Forms from the Coal 

 Measures ; by E. H. Sellards. 



[Continued from p. 134.] 



Etoblattina coriacea sp. no v. Text-figure 29 ; and Plate I, Fig- 

 ure 1J. 



Tegmina long, very slender, pointed at the apex, costal bor- 

 der slightly arched, inner border full, very thick ; nervation 

 obscure. Subcosta extending to the apex. Cubitus compara- 

 tively short, reaching only a little beyond the middle of the 

 wing. Anal area of medium extent ; anal veins about ten in 

 number, simple or forked. 



The wing is of especial interest, because of its coriaceous tex- 

 ture in which the veins are almost obscured. Only a few ter- 

 minal branches of the radius and media can be made out. The 

 branches of the subcosta are entirely obscured. A noticeable 

 feature of the w T ing is the sharp angle made by the anal area. 



Formation and Locality. — TJpper Coal Measures, Lawrence, 

 Kansas. Type in the University of Kansas collection. 



Etoblattina Hilliana ? Plate I, Figure 4. 



Scudder, Bull. IT. S. Geol. Surv., No. 124, 1895, p. 99, pi. viii, fig. 11. 



The wing of Figure 4, Plate I, is doubtfully referred to E. 

 Hilliana. The subcostal area is broader than in the type, and 

 the media apparently is not so sinuous. 



Formation and Locality. — Coal Measures, Mazon Creek, 

 Illinois. 



Spiloblattina. 



Scudder, Proc. Acad. Nat. Sci. of Philadelphia, p. 35, 1885 ; Mem. Boston 

 Soc. Nat. Hist., vol. iv, p. 461, 1890. 



The genus Spiloblattina was proposed by Scndder to include 

 four species of cockroaches from Fairplay, Colorado. The 

 essential characters of the genus are the wide divergence of 

 the radius and media, and especially of the media and cubitus 

 beyond the middle of the wing, and their subsequent conver- 

 gence enclosing an elongate or ovate area, the " stigma." 

 Associated with these are other well-defined characters, as 

 the thin tegmina marked with light and dark patches,- and dark 

 bands accompanying the veins. The relative distribution of 

 the veins and their areas in this genus are practically the same 

 as in some species of Etoblattina. Nevertheless, the Spiloblat- 

 tina group of species, with thin variegated front and hind wings, 

 is evidently a natural one, and without doubt merits generic 

 rank. The sterna of Spiloblattina appear from some Kansas 



Am. Jour. Sci.— Fourth Series, Vol. XVIII, No. 105. — September, 1904. 

 15 



