r60 NEW YORK STATE MUSEUM 



point, and to urge the consideration of a modified classification 

 as an alternative working hypotheisis. 



Recent work of Kemp and Smyth 



At this writing the latest published reports on the Adirondack 

 work embody the results reached up to the close of the field work 

 of 1897 only; the more recent results not being available, unfor- 

 tunately, for comparative purposes, because unpublished. This- 

 is more specially true of Prof. Kemp's work, a recent consulta- 

 tion with Prof. Smyth having made him and the writer familiar 

 with each other's results. But in the 17th annual report of the- 

 state geologist appear papers of great importance by both Kemp 

 and Smyth, which have bearing on the subject under discussion. 



Kemp's report deals mainly with the extreme southeast por- 

 tion of the region. He shows the presence of considerable bodies 

 of augite syenite which he classes with the general group of 

 gneisses, series 1, as the "Whitehall type" of gneiss. He classes 

 them thus, since they are gneissoid and involved with other 

 gneisses, and since no opportunity was afforded for determining 

 their relations to the anorthosite,that beingabsent in thedistrict. 

 He remarks also the abundance of crystalline limestone and the 

 various gneisses, in large part of probable sedimentary origin^ 

 which are everywhere associated with it. He also shows that 

 much of a granitic rock, sometimes quite massive but more often 

 gneissoid, occurs, and describes it as the " Horicon type " of the 

 gneiss group (series 1). The writer is disposed to correlate these 

 granitic rocks with the granites described in this paper as asso- 

 ciated with the syenite in the Tupper lake region, but, as he has 

 not seen the specimens, the reference is, of course, merely tenta- 

 tive. Kemp does not seem to have come across any exposures 

 which would throw light on the question of the relations of the 

 " Whitehall " gneiss (augite syenite) to the crystalline limestones 

 on the one hand, or to the granitic rocks of the " Horicon type " 

 on the other; at least no reference to these relations has been 

 noted in a careful reading of the paper. On p. 540, in describ- 

 ing the rock succession at the graphite mine in. Hague, Kemp 

 mentions an acid, titanite gneiss as forming the lowest rock seen,. 



