1913] DicJcerson: Fauna of Eocene at Marysville Buttes 285 



fifth rib is stronger than the three above and a persistent riblet 

 is found between it and the fourth rib ; the space between it and 

 the suture is twice as great as the space between the ribs above. 

 The lower whorls are flattened between the first rib and the 

 suture. 



University of California Localities 1853 and 1855. Named in 

 honor of Professor J. C. Merriam, University of California. 



The upper whorls resemble T. uvasana somewhat in apical 

 angle and ribbing, but their shape is slightly different. The 

 lower whorls bear a superficial resemblance to T. chicoensis in 

 that the suture is impressed and is bordered by a rim on the 

 whorl below and sometimes by one above. The rib below the 

 suture is much more developed in T. merriami than T. chicoensis. 

 The number of ribs in T. chicoensis is only three with four or 

 five minute revolving lines between, while there is only the one 

 mentioned above between the fourth and fifth rib in T. merriami. 



This species also occurs in the Eocene of Oregon. 



Mr. Bruce Martin collected the following "under bridge at 

 mouth of Little River, North Fork of Umpqua River, 18 miles 

 northeast of Roseburg, Umpqua Formation," California Academy 

 of Sciences Locality : 



Oliverato californica Cooper 

 Cyliebna costata Gabb 

 Morio tuberculatus Gabb 

 Loxetrema turrita Gabb 

 Fusus mathewsonii Gabb 

 Turritella uvasana Conrad 

 Amauropsis alveata Conrad 

 Turritella merriami, n.sp. 

 Pseudoliva volutaeformis Gabb 

 Phos(?) martini, n.sp. 



Eimella eanalifera Gabb 

 Cerithium carbonicola Cooper 

 Tapes eonradiana Gabb 

 Glyeimeris cf. sagittata Gabb 

 Cardita planieosta Lamarck 

 Cardium breweri Gabb 

 Crassatellites grandis Gabb 

 Modiolus ornatus (Gabb) 

 Corbula parilis Gabb 

 Lueina eumulata Gabb 



Turritella merriami is in a collection made by Mr. Vance 

 Osmont at the Tesla coal mines. 



Dimensions: Length of broken specimen (see figure 6b, plate 

 13), 30mm. 



