EDITORIAL 97 



apparent purpose of introducing a high-sounding Greek name in 

 place of the term used by me. 



In discarding the evidence of the plug-like character of the 

 intrusions near the Black Hills, Iddings states that it is probable 

 they are central remnants of small laccoliths, for the reason that 

 the prismatic columns of which they are largely composed are 

 vertical, " whereas they should be horizontal in the body of a 

 volcanic plug." Unfortunately for this dictum, the prisms in 

 many true volcanic plugs or necks, like those about Mt. Taylor, 

 New Mexico, described by Dutton, are vertical. 



In the same spirit in which Iddings discards the evidence of 

 the plug-like form of the intrusions under consideration, and 

 with equal justice, one might use his own language in reference 

 to the account he himself gives of Mt. Holmes, the new type- 

 example brought forward and of the accompanying, largely 

 ideal diagram; " He has mentioned nothing that demonstrates 

 or even indicates that it possesses the character of a plug;" it 

 might just as well be a laccolith eroded down to the feeding 

 conduit. 



The term bysmalith which Iddings seeks to substitute for plu- 

 tonic plug, means simply plug-stone, and maybe used with equal 

 propriety for both volcanic and plutonic intrusions, of plug-like 

 form ; if one wishes to make this convenient distinction the 

 terms volcanic bysmalith and plutonic bysmalith would have to be 

 used. I fail to see any advantage in such a clumsy nomencla- 

 ture. The word bysmalith is so similar to bathylith, already in 

 the field and also used by Iddings in the article referred to, that 

 confusion must arise if this rechristening is permitted. It seems 

 to me that American geologists should use their mother tongue 

 whenever it can be made to serve, and usually it will be found 

 rich enough to express all the ideas they may have, instead of 

 searching the dictionaries of the dead languages for more or less 

 accurate translations of plain English terms. 



Israel C. Russell. 



[The use of the term volcanic instead of plutonic in referring to the intru- 

 sions in question was inadvertent ; much of the assumed distinction in the use 



