ft) 



-t; 

 O 



•- i 



Pm 

 O 



w 



© g 



2.5 



.X3 O 



Outer wall of 



sicula slightly 



curved, inner wall 



straight ; first 



theca very long. 



Proximal end 



curved 



backward. 



Apex of sicula 



on a level with 



the second thecal 



aperture ; first 



theca short. 



Length of 

 sicula. 



.5 s 



l—V 3 



-8? 



.5 s 



|soX) 

 Ah 



No. of 

 t he eye 



(distal). 



24 in 1 inch 

 (9 to 10 in 10 



mm.). 



24 in 1 inch 



(9 to 10 in 10 



mm.). 



24 in 1 inch 



(9 to 10 in 10 



mm.). 



No. of 



thee® 



(proximal). 



iH o 



28 to 32 in 



1 inch (11 to 13 



in 10 mm.). 



30 to 32 in 



1 inch (12 to 13 



in 10 mm.). 



g 



• - -3 

 3 



-S5 



00 A 

 O rtf rH 



1+3 ■£ ci 



*8 . 



.5 """ 3 



1 5 oo 

 O !-" l © 



-a "IT 



o S 



.5 3 



j*8 



Tec* 



bo 

 0) 



.a o^r 



<a >'o 



^ n S 



CO 



o 



O 



K 



Zone of Cyrtograptus 



Murchisoni to zone of 



C. Lundgreni. 



s 



Si I 



8 



S3 



Zone of Cyrtograptus 



Murchisoni and possibly 



higher zones. 



03 



O 



i-5 



Pencerrig, 



Trecoed, River Irfon, 



etc. 



o 



Pn 



P 



o 



p 



03 

 > 



a 



03. 



*» 



