Palaeozoic Araclinida of N^orth America. 



45 



The abdomen is torn in the middle, as shown in the text figure 

 and on the photograph. If straightened out, it would measure about 

 35 mm. 



Found in the Pennsylvanic (Lower Allegheny) of Mazon Creek, 

 Illinois. 



Eoscorpius granulosus n. sp. 

 Plates II, fig. 10 ; III, figs, ii, I2 ; text fig. 9. 



This species is represented by three specimens in the possession 

 of the Peabody Museum, labelled respectively as Nos. 128, 129 and 130. 

 I designate No. 128 as 

 the holo type, it being 

 the best preserved. 

 Only the obverse of 

 the nodule containing 

 the type specimen is 

 in existence (PI. II, 

 fig. 10; text fig. 9). 

 It shows the cephalo- 

 thorax with the median 

 eyes, abdomen, three 

 and a quarter segments 

 of the post-abdomen, 

 mandibles, left pedi- 

 palp anf fragments of 

 right pedipalp and of 

 two legs, one on each 

 side of the body. 



Thecephalothoraxis p.^ 



somewhat like that of p^„^^^ g.-Eoscorpius granulosus n. sp., holotype, 

 the precedmg species. Peabody Mus. No. 128. Nat. size. 



It is 9.5 mm. long 



and 12 mm. wide at posterior edge which is slightly recurved. 

 The oval eyes are almost their diameter from the anterior edge. 

 A median ridge runs from the edge of the semicircular decli- 

 vity anteriorly, dividing almost in the middle of the cephalothorax 

 and surrounding the depression representing the mould of the eye 

 tubercle. The anterior angles of the cephalothorax are quite rounded, 

 while the posterior ones are scarcely blunted. The abdomen is 30 mm. 

 long, the tergites considerably separated from each other showing that 

 the specimen was a gravid female. The length of the tergites increases 

 gradually backward, so that the first is the shortest and the seventh 



