164 S. IT. SCUDDER ON SPINED MYRIAPODS 



is equal in length to the remainder of the leg (though this point is obscure and doubtful), 

 slender and compressed, with only a faint sign in one of any carina, equal in width through- 

 out, and about six or seven times as long as broad ; the rest of the leg tapers to a bluntly 

 rounded p int, with no possibility of making out distinct joints from the obscurity of its 

 preservation ; on two, a tapering, curved claw appears to be present, not sharply pointed, 

 less than 0.5 mm. long ; the entire leg is 5 mm. long and its greatest breadth 0.4 mm. 



The next specimen referred here, and which was received from Mr. Worthen (PL 12, fig. 6), 

 presents a nearly straight and uniform ventral view. There is no apparent sign of taper- 

 ing toward the head, the anterior half being nearly uniform in size ; behind this it tapers 

 gradually and uniformly, so that the hinder end is about two-thirds the width of the 

 anterior half. The length of the creature is 98 mm., its greatest breadth 6 mm., narrowing 

 to 4 mm. at the tail. The head and first segment (PI. 12, fig. 5) are together represented 

 by a deep and large, well rounded depression, in the intaglio half, as broad as the segments 

 behind it, and together much more than equalling two of them ; the head would appear 

 to have been much broader than deep and higher than broad, drooping and passing below 

 to a lower plane than the rest of the body, and with the next segment forming a compact 

 globe ; next the lower front edge of this globe is a slight rounded depression (indicating a 

 slight boss in the living creature), on which are half a dozen ovate wartlets or granules 

 which may indicate the eye, but it is too vague for any assertion. 



The segments are many of them obscure, but appear at first sight very numerous, 

 numbering some sixty or seventy, but as these are the ventral plates the real number is 

 only half of this ; the whole body is blurred in parts, rendering it difficult or impossible 

 to be more precise ; these ventral plates average 1.5 mm. in length, and where they are 

 distinct, as in the broadest part, they are four times as broad as long ; they are well 

 arched transversely, indicating a well rounded body, and have their anterior half stoutly 

 ridged. They show in places series of short, longitudinal, slightly oblique, slight and 

 irregular corrugations. Traces of the insertions of the legs can be seen on many segments, 

 situated in the centre of the front margin of the depressed portions ; above them (that is , 

 toward the spined margin) there is a slight trace here and there of stigmata, but I have 

 not been able, so poorly preserved is the fossil, to detect any of the crateriform bran- 

 chial cups, described in Acantheiyestes major. The subdorsal spines of a single row 

 are present on many of the segments, but poorly preserved, and are small, being only 

 about one-third the length of the width of the segment on which they occur, rather stout 

 at base, beyond this tapering, and curving slightly backward, and at first sight apparently 

 simple ; one, however, faintly shows a part beyond the apparent tip, indicating that the 

 others have been broken ; and as this is provided also with a slight anterior spinule in 

 the middle, and a basal posterior thorn, it agrees entirely with the last specimen described. 

 There are a couple of fragments of legs just beneath the junction of the first and second 

 ventral plates behind the head, situated side by side and touching ; they apparently rep- 

 resent the basal joints. We have here new proof that the first segment, represented by one 

 dorsal plate behind the head, bore two pair of legs in these myriapods, and the additional 

 evidence derived from the presence of the complete ventral segments to which they were 

 attached. There is besides only a single indication of what may be a leg, which appears at 

 about the eighth ventral plate behind the head, on the side opposite to that to which the 



