Correspondendence. 281 
The study of the "Mediai Tertia?'i/" is far less complex than that of 
the "■Fossil Shells'' &c., owing to the facts that copies of it are much com- 
moner, and the worlv seems never to have had but one edition in any of 
its parts except of course the covers. There are, to be sure, several un- 
settled points relating to this work, but, no one is more capable to deal 
with them than is Dr. Dall. 
Washington, D. C. Feb. 25, 1893. Gilbert D. Harris. 
Geological Society of Washington, — A Geological Society has re- 
cently been organized in Washington, D. C, for the presentation and 
discussion of topics of interest to geologists. The constitution and 
standing rules were subscribed to by 109 founders at the first public 
meeting, March 8th, 1893. Its members are of two classes, active and 
corresponding. The annual dues of the first are $2.00, and of the sec- 
ond, $1.00. Meetings will be held on the second, and generally also on 
the fourth Wednesday of each month, from October to May, inclusive. 
The journals and bulletins of the various societies appear to furnish 
sufficient opportunity for the publication of papers read before the soci- 
ety, so that for the present the society will not undertake to publish the 
papers presented. It will probably issue one bulletin each year contain- 
ing the address of the retiring president and such other matter as the 
council directs. 
All publications, and if desired, notices of the meetings also, will be 
sent to corresponding as well as active members. 
This circular letter, with the accompanying pamphlet containing the 
constitution, standing rules, lists of founders and officers of the society, 
is issued for the information of members and all other persons who are 
interested in the progress of geological science. 
Washington, T). C, March 18, 1893. J. S. Diller, Secretary. 
The fauna of Tucumcari. — In an article in your March number, p. 
213, "Remarks on a part of the Review of the Third Texas Report," by 
Prof. Jules Marcou. I have been quoted as having said "the fauna 
(meaning that of the Tucumcari region) is an upper Jurassic fauna." 
This quotation is correct, but as stated by professor Marcou, it was a 
verbal opinion given in 1889. I do not see why this should be consid- 
ered of any value, but since it has been twice quoted and is evidently 
being used in this controversy, it is only proper to state that I do not at 
present consider myself qualified to give any opinion upon this question. 
Professor Hill showed me at Ithaca, in the summer of 1891, his superb 
series of fossils collected in Texas some years before, and demonstrated 
to my satisfaction that it would be essential for me to study his local- 
ities in the field or his collection, and perhaps both of these sources 
of information, before publishing anything about Tucumcari. I have 
at present absolutely no opinion about the age of the rocks of this re- 
gion, the evidence on either side being very conflicting and my Informa- 
tion at present far too limited. 
Boston, March 16, 1893. Alpiieus Hyatt. 
