mud form and some almost smooth, Orthi sinuata and P. ponderson also occur here for the P. lynx make of 95% of the fronds. Hydan come in blue shales with more li. and in thicker beds than Talar for about 11 feet. The li. are replace with P. ponderson and here they usually seem piled together like canews standing on edge. This same species also record in the shales but here in far less abundance. In other words where P. ponderson has clear waters they grow in such abundance as to make li., but when the waters muddy they are far less nu- mmerous. On the other hand P. lynx grows in somewhat muddy waters and do not make li. beds. At the deeper and thickly grown of P. ponderson I laid the dividing line between the Orth. Autumn formation and the Arenheim. There certainly is no fault to be seen here for the Ratios again continue upward