70 RECONNAISSANCE IN NORTHERN ALASKA IN 1901. 



instance of which is shown ;it Crag Peak. In miles >outh of Hunt Fork and -ii miles 

 west of John River. Hero the cleavage trends N. 35 K. and dips northwest at an 

 angle of 85°. Four miles north of this point, on the wes( side of John River, 

 occurs another good instance, in which the cleavage trends N. 70 K.. with dip to 



the north at an angle of 45°. Also where the river crosses the sixty -eighth parallel 

 a cleavage is found trending east and west, with dip south at an angle of 30 . 



Age. — No fossils have been found 'in place in this series, but on the basis of 

 abundant Lower Carboniferous forms obtained in the stream pebbles of the region, 

 and the lithologic resemblance of these pebbles to the rocks of the series, and also 

 from the relation of the series to the Lisburne formation (which is considered 

 Devonian and seems to underlie it), the Fickett series is provisionally assigned to the 

 Lower Carboniferous. Following is a list of the fossil forms collected by the writer 

 within the area occupied by the series, largely on the headwaters of John and Anak- 

 tuvuk rivers. They have been identified by Mr. Schuchert, who reports as follows: 



Fossils from the Fickett series. 



Locality 493. Lithostrotion (of the group in which the corallites are not in close embrace). 



Locality 495. Spirifer striatus Martin, Productus scabriculus Martin, and Spirifer near S. neglectus 

 Hall. 



Locality 513. Productus scabriculus Martin. 



Locality 520. Productus seniireticulatus Martin. 



Locality 521. Spirifer striatus Martin; Productus, a very small undetermined species, and Cysto- 

 dictya nearest to C. lineata. 



Locality 522. Spirifer striatus Martin and Fenestella. 



Locality 525. Spirifer striatus Martin and Spiriferina cristata Schlotheim? 



Locality 534. Streblotrypa near nicklesi Vine; Fenestella, several species, one of which is near F. 

 cestriensis Ulrich; Cystodictya, Pinnatopora, and Rhombopora. 



The above eight localities represent one formation, in the upper portion of the Lower Carbonifer- 

 ous. This fauna, however, is unlike that of the Mississippi Valley in that it does not have its charac- 

 terizing fossils, as the screw-like bryozoan Archimedes and the Mastoid genus Pentremites. 

 parisons must be deferred until larger collections are at hand. 



Localities 497 and 529 have a Syringopora much like S. multattenuata of the Upper Carboniferous. 

 This genus, however, has little stratigraphic value, but the development of the species present is 

 indicative of Carboniferous. 



Localities 511, 518, and 454 are represented by a crinoidal limestone, apparently the same as at 

 localities 525 and 521 and probably from the horizon of the latter. 



Localities 463 and 464 represent another horizon, since the lithology is quite different from any of 

 the other localities. The only fossils present are large crinoidal columns like those of the Lower Car- 

 boniferous. 



Locality 461 also has large crinoid columns and may represent the Lower Carboniferous. 



The above localities probably all represent the same Lower Carboniferous formation as that of 

 the specimens from localities 493, 495, 513, 520, 521, 522, 525, and 534. 



Locality 519 has Fenestella, Cystodictya f and crinoid columns. The material is unsatisfactory 

 and all I can do is to state that it indicates either Devonian or Carboniferous. 



