PLATE IX. 



LAOTIRA CAMBRIA (p. 32). 



Fig. 1. View of an exumbrella in which the lobes are but slightly indicated. 



Fig. la. Subuinbrella view of fig. 1, showing a tendency to irregularity, which is indicated in a 



somewhat different type by fig. 6 of PI. VIII. 

 Fig. 2. Subumbrella view of a very rotund specimen, which, though obscured by adhered siliceous 



matter, shows a slightly transverse arrangement. 

 Fig. 3. A well-preserved individual having 5 principal exumbrella lobes and 2 small interradial 



lobes. 

 Fig. 3a. Subumbrella view of fig. 3. The subumbrella lobes are strongly defined. An irregularity 



of the meeting of the lobes at the center is shown, which is carried still further in figs. 



5a, 6a, and 7a. 

 Fig. 4. Exumbrella view of a more rotund specimen than fig. 3. 

 Figs. 5, 5a. Exumbrella and subumbrella views of an individual in which the bilateral arrangement 



of the subumbrella surface is indicated, but not so strongly as in fig. 6a. 

 Figs. 6, 6a. Exumbrella and subumbrella views of a specimen in which the bilateral arrangement 



of the lobes is strongly marked. 

 Figs. 7, 7a. Exumbrella and subumbrella views of umbrella lobes still more irregularly arranged 



than in figs. 5 or 6. 



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