CARADOCIAN CYSTIDEA FROM GIRVAN. 



463 



Fig, 65. — P. squamosa. 

 Brit. Mus. E 15925. 



Fig. 66. - P. robvsla. 



E. Billings' figure 



and description. 



Fig. 67.— p. elegans. 

 Brit. Mus. E 7683. 



Fig. 68. —P. filitexta. 

 Brit. Mus. E 16041. 



Fig. 69.— p. Rugeri. 

 Holotype. 



Fig. 70. — P. anglica. 

 Holotype, restored. 



Fig. 71.— p. gihha. 

 G172. 



Fig. Ib.—P.foriolus. 

 G135. 



YiG. li,— P. procera. Fig. 73. — P. quadrata. i^'iG. 74. — P. foriolus. 



Holotype. G 142. Holotype. 



Tkxt-figs. 65-75. — Pectinirhomb 10-14 in various species of PUuroeystis. These lia%'e all, except fig. 66, been drawn with the 

 aid of the camera, to the same scale, approximately x 5 diameters. Plate 14 is on the left, plate 10 on the right. A few 

 species are not represented in these figures because their pectinirhombs are not yet known well enough. 

 TRANS. ROY. SOC. EDIN., VOL. XLIX. PART II. (NO. 6). 61 



