1 84 AXEL LEONARD MELANDER 



can be surmised from the imperfect fossil remains. Like many 

 archaic or young types, its body-chitinization is not complete, 

 and its frailer structure is represented but vaguely in the same 

 rocks that bear such excellent witness of the rulership of the 

 scorpion and the Anthracomart. 



Order SCORPIONES. 

 Family Eoscorpionidae Scudder. 



6. Eoscorpius carbonarius Meek and Worthen. 

 Geol. Surv. III. Vol. Ill, p. 560, text figure. 



This specimen is the reverse of the one illustrated by Meek 

 and Worthen, being the opposite portion of the same ferrugi- 

 nous concretion. 



Cotype. Pal. Coll. No. 8949. 



CLASS INSECTA. 



Division PAL^ODICTYOPTERA Goldenberg. 



Section ORTHOPTEROIDEA Scudder. 



Family Palaeoblattariae Scudder. 



7. Mylacris Gurleyi Scudder. 



Bull. U. S. Geol. Surv., No. 124 (1895), p. 43, Plate I, Fig. 5. 



Type. Pal. Coll. No. 6389. 



8. Mylacris Mansfield! Scudder. 



Mem. Bost. Soc. Nat. Hist., Vol. Ill, p. 47, Plate 5, Fig. 15. 



This is the specimen mentioned by Scudder as coming from 

 Vermilion county, 111., the original type of the species being 

 from Cannelton, Pa. 



Pal. Coll. No. 9237. 



Q. Promylacris ovalis Scudder. 



Proc. Ac. Nat. Sci., Phila., 1885, pp. 34, 35. 



Type. Pal. Coll. No. 6387. 



Another well-preserved specimen of slightly smaller size 

 appears to belong with this species. It comes from the same 

 locality and the same formation. 



Pal. Coll. No. 9238. 



10. Lithomylacris simplex Scudder. 



Me7n. Bost. Soc. Nat. Hist., Vol. Ill (1879), PP- 5i. 52, Plate 5, Fig. 5. 



Type. Pal. Coll. No. 6390. 



