EXPLANATION OF PLATE 17 



Fig. 1. Aiuria sp. No. 11258, Coll. Invert. Palae. Univ. Calif., loe. 1173. A 

 cross-section showing the long funnels reaching from one septum to the other 

 and somewhat beyond; this is characteristic of this genus. 



Fig. 2. Scliizaster calif omica Weaver. No. 11259, Coll. Invert. Palae. Univ. 

 Calif., loe. 2755. Natural size. 



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