raiLOBiro. 



- li;i\f tin' -.mi.: rel.i'i ii /'. in' 'lit (lit- -epaiatm- fur 



are ver> -hori. deeplj inoiaed .it their inner extremities, while tin- lol.e- tin 

 are all continent along the dm--al fun. 



\ ringlt -t-|. further 111 tin- obliteration of tJ ,il furrow-, causing 



the Hr>t ami second loin- to iiecomo. wholly continent. \voiilil produce that condition 

 of the glahella which Schmidt has (.generic value. proposing for 



specie- of tin- structure the name Mm ( Moiiorm'liux eiueini.). \\ith t he 



i-vidtMice of closi- specific relationship Between P. >> and /'. intrnitxlius. it 



would ho inalmis..aMo to employ this term here, though the former may l>e reganle.! 

 as a stepping stone from the typical />!? to that condition of extreme 



scence of the glahellar Iol>e8 exempli; >ius. 



'. I'terj/yvutftoptu eboracftu, fnnu th<- san, ii.il rentorcd. 



The occipital ring of / ler than in /'. i>if?nm;lii and bears a 



conspicuous tul-eicle at its center. Genal spines are also present The surface of 

 the glabella is generally tubercled. and on the free cheeks there are faint. ramif\ 

 minutely punctated grooves. The general form of the thorax is somewhat less 

 tapering than in /'. interim <i 



The pygidiuin is scarcely triangular, the lateral slopes gentle. The axis bean* 



about ten annui and the pleura; eight rilis which are quite flat, separated by 



narrow furrow-, the tir-t of which i- shorter than the rest, becoming obsolete 



at a con-ideral' ice from the margin: six of the rihs hear line, oblique linear 



i. 



itiiiii and locality 



i IIMIHTI. n. 



This name i- p. - whose foatup together character! 



thoiigb no single example has been o which retains all the parts. Mo 



imens ;ire heads and tails, and the he-t of them a cephalon with nine 

 thoracic segment- A- the cliaracters of the more common species of the .Minn, 

 rock-. /'. /'/ i. it \\ill he -utlicient to point out the 



(lilFerential characters of /'. .Inch does nut vary from the former in gei 



. neoe wulbi- :> Sclcnc dc 81. 



if*. -).* 



