25 



Cryptonymus caudatus. Anff., 1852. 



Pal^ontologia Scandinavia, P. 88, Pl. iv. Fig. 2. 

 "Pygidium triangular with a raucronated tail, smooth, 

 with 5 or 6 j^leuras on each side. 

 Locality : Regions T>. and E., Norway, Brevig." 



Cryptontmus steietus. Anff., 1852. 

 Pal.eontol. Scandinavia, P. 80, Pl, iv, Fig. 13. 



"Pygidium smooth and pointed ; pleurae ten ; axis 

 with about seventeen notches, which are obliterated in 

 the centre. 



Locality : Regions D. and E., Dalecarlia." 



Cryptonymus sexcostatus. Salter, 1848. 

 "Length about an inch and a half, breadth an inch. 

 General form broad-ovate ; the head and tail convex, 

 the body rather flat. Head about equal in length to 

 the tail, but shorter than the thorax ; its shape triangu- 

 lar, the lateral angles produced, the front rounded gib- 

 bous, and overhanging. The glabella occupies full one 

 third of the width of the head in front, where it is much 

 inflated and more than hemispherical ; it overhangs the 

 margin, which, as is usual in the genus, is not distinctly 

 separated from it in front, but within the margin and 

 above it on the glabella, there is a strong furrow which 

 runs quite across the glabella, separating from it a thick 

 prominent ridge (fig. 3, a) so completely that it apj^ears 

 not to form a part of the glabella, but to belong to the 

 thickened front margin.* The entire glabella is pyri- 

 form, constricted behind to half its width, and separated 



* This singular furrow is probably the place of the facial suture- 



25 " 2,forPL.iv,FiG.2,readPx.xLi,FiG.ll. 



" " 6, " STRiETUS, read striatus. 



" •' 7, " P. 80, Pl. IV, read P. 89, Pl. xli. 



