150 S. H. SCUDDER ON SPINED MYRIAPODS 



Order MYRIAPODA. 



Suborder ARCHIPOLYPODA. 



Paleozoic myriapods, with a fusiform body, largest near the middle of the anterior half 

 or third, the head appendages borne upon a angle segment ; each segment behind the head 

 composed of a single dorsal and two ventral plates, the dorsal of nearly uniform length 

 superiorly and inferiorly, occupying most of the sides as well as the top of the body ; desti- 

 tute of foramina repugnatoria, and divided into a ridged anterior and flat posterior portion, 

 the anterior provided with longitudinal rows of spines or tubercles ; the ventral plates occu- 

 pying the entire ventral portion, each bearing a pair of long jointed legs, and furnished 

 outside of them with large spiracles, the mouth transversely disposed. 



Family Euphoberidae. 



Archipolypoda armed with very large forked or branching spines, occasionally reduced 

 to tubercles, running in several uniform rows along the back or sides of the body, and 

 attached to the dorsal plates ; the legs compressed, the second joint much longer than any 

 of the others and the whole adapted to swimming ; those of opposite sides well separated at 

 base, and having between their insertions a pair of branchial appendages. 



GenUS ACANTHERPESTES {3.xav0ajpt:w.) 



Acantheriiestes Meek and Worthen, Geol. Surv. 111., Ill, p. 559 (hypothetical). 



Spines bifurcate at tip and arrayed in subdorsal, pleurodorsal and lateral rows. Segments 

 three or more than three times as broad as long. 



The name Acantherpestes was suggested for one of the species which* falls within this 

 group by Messrs. Meek and Worthen, in case it did not agree with the genus Euphoberia 

 (to which the species itself was referred with question marks) in having two ventral plates 

 corresponding to each dorsal plate. This it does possess, as indeed the very figure they pre- 

 sent shows, two pairs of legs being pictured as corresponding to each dorsal plate. Not- 

 withstanding this, and notwithstanding the impropriety of suggesting hypothetical or con- 

 ditional names for animals whose affinities are not clearly understood, the name is a good 

 one, and rather than burden our heavily taxed science with synonymy, it is brought into 

 requisition. 



Acantherpestes major. 



PI. 10, 11, figs. 1-4, 6-8, 10, 11. 

 Euphoberia ft major Meek and Worthen. Amer. Journ. Sc. Arts, [2], XLVI, 25-27 ; 



—lb., Geol. Surv. Ill, III, 558-559, fig. (1868). 



The figure was reproduced by Woodward in the Geol. Mag., X, p. 105 (1873), and also 

 in his Monograph of the Merostomata, p. 172, fig. 62 (1872). 



The specimens upon which this species was founded were very fragmentary, the one fig- 

 ured consisting of only seven segments with a part of one spine, the spine-bases and sev- 

 eral imperfect legs. Two other specimens have been placed in my hand by Mr. J. C. Carr, 



