XX. SUPPLEMENTAKT NOTE ON FosSIL MtRIAPODS. By SaMUEL H. ScUDDER. 



Read Oct. 20, 1875. 



\V HEN my paper upon these insects was published by this Society,^ the drawings with 

 which it was intended to accompany it were unfortunately mislaid. Having recently 

 been found, and no further material having been discovered since they were drawn, 

 I publish the figures for the assistance of any one endeavoring to study these very obscure 

 remains. AH the species described in the memoir referred to are illustrated here. 



Fig. 1 represents two contiguous segments of Xylobms sigillarice., showing the shape of 

 the segments and frustra, with the position and form of the lateral pores and legs, those 

 only of one side being shown ; in this and the two subsequent figures the anterior end 

 of the segment is at the right hand. 



Fig. 2 shows corresponding segments of Xylohius similis, with the omission of the lat- 

 eral pores and legs, these being unknown. 



Fig. 3 gives the same parts of Xylohius fraetus, with the legs and the lateral pores, the 

 former of their supposed length. 



Fig. 4 exhibits a single segment of Xylohius Dawsoni ; here the division lines of the 

 frustra are represented as strongly curved, only to exhibit the prominence of the anterior 

 ridge ; in this figure and the next, the anterior end of the segment is at the left hand ; the 

 slight divarication of the division lines of the frustra in this figure represents the appear- 

 ance they present at the anterior exti'emity of the body. 



Fig. 5 represents a similar segment of Arckiulus xylohioides, showing its shape, the 



'Memoirs, Vol. II, Part, ir, p. 211, Ou the Carboniferous Myriapods preserved in the Sigillarian Stumps of Kova Scotia. 



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