252 PALEONTOLOGY. 



or even quite sharp on their upper edges. The specimen is in such a state 

 of preservation that it is impossible to detect the specific characters, and is 

 chiefly interesting on account of the association in which it is found. The 

 genus Miclielina is not common in this country in rocks above the Devonian, 

 although very abundant in many of the formations of that series, and has 

 been recognized in several species in the Carboniforous rocks of Europe, 

 This species, therefore, furnishes another instance of the mingling of 

 Devonian and Carboniferous forms in the rocks of the age to which we 

 suppose these to belong (viz, Waverly group), showing intimate relations, 

 if not absolute transition without break, from the Devonian to the Lower 

 Carboniferous in several widely distant parts of the country, 



BRACHIOPODA. 



Genus STREPTORHYNCHUS King. 



STREPTORHYNCHUS EQUIVALVrS. 

 Plate IV, figs. 1-2. 



Orthis equivalvis Hall, Geol. Eept. Iowa, vol. 1, iJt. 2, p, 490, pi. 2, fig, 6, 



Specimens of a species of Streptorhjnchus, having characters very 

 similar to many of those occuringin the Burlington sandstones, occur in the 

 rocks of this formation at Ogden and Logan Canons, Wahsatch Range, 

 Utah. The shell is at all times a very variable one, and not easily deter- 

 mined with satisfaction. The specimen representedby fig. 1, plate IV, is 

 rather wider than most of those above referred to, but resembles them in 

 form except in this particular, and in want of the sinus which often marks 

 them. The alternations of coarser and finer striae is a common character. 

 The specimen represented by fig. 2 of the same plate is also a not unusual 

 form, although shorter than the generality of individuals. The specimen 

 fig. 1 is from Ogden Canon, and fig. 2 from Logan Canon. Collected by 

 S. F. Emmons, esq. 



STREPTORHYNCHUS INFLATUS. 

 Plate IV, fig. 3. 



StreptorhyncJms inflatus White & Whitfield, Troc, Bost, Soc. Nat, Hist , vol. viii, 1862, 

 p. 293. 

 The specimen fig. 3, plate IV, possesses the character of the above-cited 

 species in all particulars as far as can be ascertained from the specimen, except 



