Plate 28. 



Fig. 1. Pcrscplioiuister Ji(i1ij-(>(i< iiiik : iictinal view of type, eiiliir.i,'ed, p. 131. 



2. Dipsdcastcr diaplionis ; !il);ietinal view of type, enlarsed, p. 152. 



3. Pdlac/iastcr HplmcriopJax ; abactinal view of type, enlarged, p. 154. 



