FROM THE CARBONIFEROUS FORMATION. 177 



striate surface of the body may be mentioned. It would seem in some of its features to 

 have closer resemblances than other Euphoberiae to the genus Amynilyspes. 



Euphoberia anguilla, nov. sp. 

 PL 12, fig. 20. 



The single specimen upon which this species is founded is very obscure, but differs so 

 much from all the others in the parts that can be made out that it must be referred to a 

 distinct species. It is probably a complete animal preserved so as to show a dorsal aspect, 

 bent laterally but not abruptly behind the middle, and the whole, besides, curved in a 

 sinuous manner. The body is remarkably long and slender, broadest from the seventh to 

 tenth segments, tapering in front somewhat rapidly, so that the head, which is somewhat 

 narrower than the segment behind it, is scarcely more than half as broad as the broadest 

 part of the body ; behind the tenth segment it tapers very gradually indeed and with great 

 uniformity over considerably more than half the body, so that the hinder end is only 

 two-fifths the width of the broadest part ; this and its serpentine position give it an eel-like 

 appearance ; the length of the body is about 50 mm. ; its greatest breadth 3 mm. ; its 

 breadth at posterior extremity 1.2 mm. The head, as stated, is narrower than the following 

 segment and of the same length, subquadrate in form with a flatly rounded front ; no 

 appendages can be made out. The segments of the body are difficult to enumerate, owing 

 to the obscurity of certain parts, and especially at the bend of the body, but there are 

 somewhere between 32 and 36 and probably the number is 34. The body, although almost 

 completely flattened in preservation, does not wholly conceal evidence of a former trans- 

 verse ridging of the anterior part of each segment, not shown in the figure ; probably also 

 the body was cylindrical. The segments themselves vary considerably in their proportions, 

 those at the posterior end being much longer in proportion to their width than in the other 

 parts of the body. The last six or seven segments for instance show a gradation from an 

 almost perfectly square form, in the last segment, to a quadrate segment twice as broad as 

 long ; while directly in front of this, and also in the broadest part of the body, they are three 

 times as broad as long. 



Marks of the position of some of the subdorsal spines can be made out with difficulty, 

 showing that these were not distant from each other. There its also on one side of the 

 broadest part of the body a faint indication of a simple, straight, short, conical, outward 

 directed, lateral spine, next the anterior margin of two or three successive segments ; it is 

 scarcely more than one-fourth as long as the width of the same segments. No legs are 

 visible. 



This species is remarkable for its extreme slenderness and the delicate tapering of the 

 body, and the length of the posterior segments. In all these respects it differs strikingly 

 from all the species described. 



The specimen is from Mazon Creek and was submitted for study by Mr. J. C. Carr, of 

 Morris, 111. 



Genus Amynilyspes, nov. gen. (i/iuvto, ttoandoiiai.) 



Spines so far as known simple, conical and pointed, arranged in dorsolateral rows only ; 

 segments nearly four times as broad as long, the dorsal plates terminating below in prob- 

 ably free rounded flaps ; the extremities and perhaps the whole of the body more or less 

 onisciform. 



MEMOIRS BOST. SOC. NAT. HIST. VOL. III. 23 



