528 Raymond — Succession of Faunas at Levis, P. Q. 



CI, the lowest, is characterized by horizontal species of 

 Didymograptus, such as D. nitidus and D. gracilis. 



C2, the next higher, contains D. bijidus in abundance. 



C3 is a thin zone containing that variety of I). bijidus in 

 which the two branches at an angle of about 90°. 



D is the highest zone, characterized by Diplograptus den- 

 tatus and other Diplograptids. It may be subdivided into two 

 zones, the lower one being that in which the strata are mostly 

 limestone, and the upper in which the strata are shale. The 

 total range of D. dentatus on Davidson Street is about 80 feet. 



Dl is the lower sub-zone with Shumardia granulosa, other 

 trilobites, brachiopods, and a great abundance of Dictyonema. 



D2 is the upper one, with numerous graptolites, Diplo- 

 graptus dentatus, Cryptograptus antennarius, and Climaco- 

 graptus pungens being especially abundant. 



Comparison with the section on Deep Kill, N. Y. 

 Dr. Ruedemann has described in detail the section on Deep 

 Kill, N. Y., and it w 7 ill be seen that our section agrees in 

 general with that in New York. Raedemann found in his 

 section three zones, the upper one with Diplograptus dentatus 

 and Cryptograptus antennarius, a lower one with Didymo- 

 graptus bijidus and Phyllograptus anna, and a still lower one 

 which he called the Tetragraptus zone, with " horizontal " 

 species of Didymograjjtus. These zones correspond to our 

 D2, C2 and 3, and CI, but Cl does not appear to be nearly so 

 well developed at Levis as at the Deep Kill, and most of the 

 large specimens of the " horizontal " species of Didymograptus 

 are, at Levis, found in the sub-zone of D. bijidus. At Deep 

 Kill, the lower zones, A and B, are not exposed, but Ruede- 

 raann predicted that the zone with Clonograptus flexilis and 

 C. rigidus would be found below the Didymograptus zones 

 at Point Levis. For comparison with the foreign sections, the 

 reader is referred to Dr. Kuedemann's excellent papers. 



Range of Species. 



As will be seen from the subjoined table, some of the Species 

 have a long range, Tetragraptus serra and Phyllograptus 

 ilicifolius being found in almost every zone. It must be 

 understood that the identifications are only preliminary, as the 

 bulk of the specimens have not yet been submitted to experts. 



In addition to those forms which the writer has himself col- 

 lected there have been appended to the list those forms which 

 Ami listed, which can, from their geographical locations, be 

 placed in the present section, and also species which Hall men- 

 tions as definitely associated on slabs with species whose 

 horizons are now known. These lists are kept separate from 

 the main one. Species marked with an asterisk (*) in the table 

 were listed by Hall as coming from St. Anne, Que. 



