CARBONIFEROUS MYRIAPODA OF ILLINOIS. 433 



scui'cly, and where preserved do not always show the longitudinal carina on adjacent 

 segments; legs are found at entirely eqn\l intervals up to the head, but the state of ])re- 

 servation of this general region does not permit further statement; the legs are a little 

 shorter than the width of the body. 



Length, 51 mm.; breadth, 2.75 mm.; length of legs, 2,4 mm.; of antennae 1.75 mm. 



Mazon Creek, III. Mr. W. F. B. Gurley. 



The species is peculiar for its slender form and relatively long segments combined 

 with short sharply pointed spines. In general appearance, except for its slenderness 

 and general form, it reminds one most of E. carri. 



Euphoberia tracta sp. nov. 

 PI. 36, figs. 1, 4-6. 



The first specimen seen (fig. 1) is only tolei-ably well preserved, shows both obverse 

 and reverse, and exhibits a lateral view of the greater part of the creature from the 

 head backward over about thirty-four segments. The body is gently carved, the back 

 convex, and near the head end more strongly arched, exceedingly long and slender, of 

 nearly uniform size throng'hout, there being no sign of tapering anteriorly, and it is 

 barely perceptible on the posterior fourth pi-eserved. The head is larger than the seg- 

 ments behind, and droops considerably, the larger size being indicated by the amount 

 of this droop, since the top of the head is continuous with the upper surface of the 

 body; it is well rounded in front, but nothing can be made of any appendages. Unfor- 

 tunately also none of the spines are preserved, and the only indication of their presence 

 is in occasional pits, especially at the anterior end. The segments are unusually long, 

 bringing the legs of succeeding pairs much farther apart than usual. Excepting in the 

 anterior part of the body, they are of about equal length and breadth, — a feature which 

 at once distinguishes this species from any other; the anterior part of the segments is 

 narrowly ridged, and across the middle is a less prominent and more rounded transverse 

 elevation dividing each segment into two equal subsegments. This has not been made 

 to appear in the figure. In places where best preserved the surface of the segments 

 shows a veiy delicate granulation. The legs are, as stated, far apart, a little longer 

 than the width of the narrow body, slender, tapering regularly and pointed. They show 

 slight or no signs of any unusnal basal expansion, and their joints are indistinguishable. 



Length of body, 46 mm.; width of same, 1.6 mm.; length of legs, 2.5 mm.; their basal 

 width, 0.3 mm. 



The specimen comes from Mazon Creek, 111., and is numbered 1838ab, in the collec- 

 tion of Mr. K. D. Lacoe, from whom I received it. 



The second specimen (fig. 5) is in a similar state of preservation, and was not seen until 

 the preceding was described. It shows both obverse and reverse and represents the lateral 

 view of the entire animal, if the tail end is complete, and though difiicult to determine 

 by its obscurity in certain parts, appears to be composed of about thirty-five segments 

 behind the head. The body is long and slender, tapering very inconsiderably in its pos- 

 terior half. The head appears to be still partly buried in the stone, and consequently does 

 not show its size or form, but it evidently droops very much below the lower level of 



MEMOIRS BOSTON SOC. NAT. lUST., VOL. IV. 68 



