Ph Aw ext. 
LAOTIRA CAMBRIA (p. 32). 
Figs. 1, la. Exumbrella view of a 4-lobed specimen that is fairly regular. The irregularly lobed 
subumbrella surface, fig. 1a, should be compared with the regularly lobed subumbrella 
surface of fig. 1 of Pl. V. The transition between the latter and the former is shown 
by various figures on Pls. [IX and X. 
Fias. 2, 2a. Fig. 2 is of the exumbrella surface, in which there are 6 strongly defined lobes and 
several minor lobes. The exumbrella lobes a, b, c, d correspond to the subumbrella 
lobes a, b, c, d of fig. 2a. 
Fic. 3. Exumbrella view of a large specimen in which are 7 principal lobes and several minor 
lobes. 
Fig. 4. Subumbrella view of a specimen in which the lobes are inturned very much as in the 
similar forms illustrated by figs. 3 and 4a of Pl. VII. 
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