PLATE XVII. 



LAOTIRA CAMBRIA (p. 32). 



Figs. 1, la. Exumbrella view of an irregularly lobed specimen, the subumbrella side of which (fig. 



la) has 5 strongly marked lobes; three of these show the termination of a canal at x, x, x. 

 Figs. 2, 2a. A broken specimen, the exumbrella view of which is somewhat similar to fig. 9 of PI. 



X. On the subumbrella surface (fig. 2a) there are two oral arms remaining, one of 



which shows a canal aperture at x. 

 Figs. 3, 3a. Exumbrella surface of an irregularly lobed individual, the interior canals of which 



are shown by fig. 3a. The latter view may be compared with fig. 4; also with fig. 7 of 



PI. XXIII. 

 Fig. 4. Natural section of a slightly irregular specimen, preserving seven of the interior radial 



canals. 

 Fig. 5. Portion of a complex specimen in which a constriction has begun that may indicate the 



origin of another individual by fission. 

 Fig. 6. Four-lobed individual in which the cast of the 4 radial canals and the central cavity are 



strongly defined, the size of the canals being greatly increased by a deposit of siliceous 



matter about their original casts. 

 Fig. 7. A flattened individual in which the terminations of the lobes are outlined. 

 Fig. 7a. View of the inturned lobes of the upper portion of fig. 7, the lettering of the lobes of fig. 



7a corresponding to the lettering of fig. 7. 

 Fig. 8. Exumbrella view of an irregularly lobed specimen which is somewhat flattened on the sur- 

 face of a concretion. 



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