PLATE X. 



LAOTIRA CAMBRIA (p. 32.) 



Figs. 1, la. A specimen having well-defined exumbrella lobes that may be compared with figs. 1 

 and 10 of PI. V. It differs in the introduction of some small irregular lobes. This 

 difference is further shown in the suburnbrella surface represented by fig. la. 



Fig. 2. Suburnbrella surface having 1 principal lobes and several small, indistinct lobes. 



Fig. 3. Same type as fig. 2, with more robust lobes, and a large interradial lobe, x. 



Fig. 4. Small specimen with slightly irregular suburnbrella lobes. 



Fig. 5. Exumbrella surface of an irregular character. 



Fig. 5a. Suburnbrella surface of fig. 5, in which the tendency to a transverse arrangement, shown 

 in figs. 5a and 6a of PI. IX, is developed into two centers connected by a transverse lobe. 

 One of the oral arms is shown at x. 



Figs. 6, 6a. Exumbrella and suburnbrella surfaces of a specimen in which the two surfaces cor- 

 respond quite closely in arrangement. 



Fig. T. A strongly convex suburnbrella surface. 



Fig. 8. Suburnbrella surface in which the lobes are arranged along a transverse, irregular central 

 lobe. 



Fig. 9. Exumbrella or suburnbrella surface; probably the former, showing the transverse arrange- 

 ment of .the lobes. 



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