REPORT OF THE CHIEF ASTRONOMER 519 



SESSIONAL PAPER No. 25a 



hint of a top to the series was anywhere visible and the total thickness may be 

 several times 2,500 feet. 



In the field the writer was much struck with the extreme similarity of the 

 dominant (highly feldspathic), characteristically green sandstone with the 

 sandstones which make up so much of the great Pasayten series farther east. 

 Messrs. Smith and Calkins also note a similarity between ' Mesozoic ' rocks 

 occurring at Austin Pass some twenty miles southeast of the locality now being 

 described, and the sandstones of the Pasayten* In 1S9S Dr. Stanton reported 

 on some fossils collected by Mr. W. H. Puller on Cowap creek which lies imme- 

 diately south of the Tamihy creek area. Dr. Stanton wrote : — 



' The fossils are evidently all from one horizon, which I believe to be 

 upper Jurassic, this opinion being based chiefly on the distinctly striated 

 form of AuceUa, identified with A. erringtoni (Gabb) of the California 

 upper Jurassic Mariposa beds. This species was collected at both localities. 

 The collection from Canyon (Cowap) creek includes also a fragmentary 

 Pleufomi/a and the impression of a small belemnite. 



' The collection from the divide between Canyon creek and the waters 

 of the Praser river contains the AuceUa erringtoni, a fragment of an 

 ammonite apparently belonging to the genus Stephanoceras, a small slender 

 belemnite like that from the last-mentioned locality, and the phraffmacone 

 of a large robust belemnite/ f 



It is possible that these fossils were collected from beds which belong in the 

 Tamihy series as here defined, or they may have been taken from beds more 

 directly associated with the Cultus Triassic formation. Though the text and 

 map of the report of Messrs. Smith and Calkins imply that those authors regard 

 the green sandstones as of probably Jurassic age, their statement of the litho- 

 logical resemblance of the sandstone with that of the Pasayten series suggest 

 also that the Austin Pass rocks are really Cretaceous. The present writer is 

 inclined to take the view that the Tamihy series, as represented on the Porty- 

 ninth Parallel, should be referred to the Shasta division of the Cretaceous. 

 This tentative reference has naturally little value; it invites criticism as a 

 result of much additional field work in the region. 



No other occurrences of the Tamihy series have been proved in the Boundary 

 belt, but in the floor of Cultus lake valley above the lake, and, again, on the top 

 of Pyramid ridge near the contact with the Chilliwack granodiorite batholith, 

 certain conglomeratic and sandy beds have strong similarity with certain phases 

 of the Tamihy series. 



Huntingdon Formation. 



The southern end of Sumas mountain is underlain by a cover of stratified 

 rocks which pretty clearly belong to a period much later than any other group 

 of consolidated sediments so far seen in the Boundary belt west of Osoyoos lake. 



* G. 0. Smith and F. C. Calkins, Bull. 235, U.S. Geol. Surv., 1901, p. 27. 

 t From Bull. 235, U.S. Geol. Survey, 1904, p. 27. 



