654 



SCIENCE. 



[N. S. Vol. XIV. No. 356. 



collections. Following this is the ' Review of 

 Recent Geological Literature' and the 'Author's 

 Catalogue of Recent Geological Literature.' 

 The September number contains a valuable dis- 

 cussion of 'The Basic Rocks of Northeastern 

 Maryland and their Relation to the Granite,' 

 by Alfred Gray Leonard. The author describes 

 several rocks, all from a limited area, ranging 

 from acid to ultra-basic. He attempts ' to 

 show that these types are intimately associated 

 in their geological occurrence and closely re- 

 lated in composition ; that many of the types 

 graduate into others by intermediate varieties, 

 and that they probably represent facies of one 

 original magma.' The article is accompanied 

 by four plates of microphotographs illustrating 

 rock structures, and a map showing the distri- 

 bution of the varieties in the area studied. 'A 

 Preliminary Geologic Section in Alpena and 

 Presque Isle Counties, Michigan,' by Amadeus 

 W. Grabau, has a plate showing a geological 

 section at Thunder Bay accompanied by a de- 

 scription of the various outcrops. This is fol- 

 lowed by ' Editorial Comment on the Archsean 

 of the Alps.' 



The October number of the American Jour- 

 nal of Mathemathics (Vol. XXIII., No. 4) has 

 the following articles : 



Memoir on the Algebra of Symbolic Logic, 

 by A. N. Whitehead ; Secular Perturbations of 

 the Planets, by G. W. Hill ; Representation 

 of Linear Groups as Transitive Substitution 

 Groups, by L. E. Dickson ; A Class of Number 

 Systems in Five Units, by G. P. Starkweather. 



The Osprey for August contains articles on 

 'Birds about Lake Tahoe,' by Milton S. Ray ; 

 ' Life History of the Prairie Warbler,' by Jno. 

 W. Daniels, Jr. ; ' Camping on the Old Camp 

 Grounds,' II., by Paul Bartsch ; 'Cage Birds 

 of Calcutta,' by Frank Finn, and the seventh 

 instalment of ' The Osprey or Fishhawk : Its 

 Characteristics and Habits,' by Theodore Jill. 



DISCUSSION AND CORRESPONDENCE. 



DIFFERENTIATION OF SUBJECTS AND TITLES IN 



COLLEGES. 



In your last issue Professor F. W. Rane 

 makes objection to the all-comprising title of 

 professor of agriculture, and very properly 



points out that the subject is now so differen- 

 tiated that the nomenclature in professorship 

 should follow suit. While the claim is per- 

 fectly proper, I cannot suppress a smile in read- 

 ing the signature of the ' Professor of Horticul- 

 ture and Forestry.' Why should not Mr. Rane 

 begin differentiation at home ? Horticulture and 

 forestry are two so widely different subjects 

 that the man who proposes to teach them both 

 must, indeed, be able to turn his coat most 

 readily. Both, to be sure, have to deal with 

 trees, being both branches of the wider field of 

 arboriculture ; but each deals with entirely 

 different classes of trees, for entirely different 

 purposes by, entirely different — I might almost 

 say opposite — methods. The forester is after 

 the substance of the tree ; the final object of his 

 efforts is attained by the cutting, the removal 

 of the tree. The horticulturist's object is not 

 the substance but the fruit, or, if he be a land- 

 scape gardener, the form and beauty of the 

 tree, both aims being only fulfilled by the pres- 

 ence of the tree. These different objects are 

 attained by entirely different methods, as could 

 be readily pointed out, did space permit. 



I would not wish to discourage any laudable 

 attempt to make students of horticulture and 

 of other agricultural branches know something 

 of forestry, but it is a question whether they 

 can get much professional knowledge of either 

 the one or the other subject from an undiffer- 

 entiated professor of horticulture and forestry. 

 As we have now two fully organized colleges of 

 forestry, the one at Yale with two, the other at 

 Cornell with three, professors of forestry, with- 

 out any other branches to teach, it would ap- 

 pear quite time for other colleges, who find it 

 necessary or desirable to educate foresters, to 

 realize the wide difference between the various 

 branches of arboriculture, and not mix up 

 botany, horticulture, landscape gardening and 

 forestry in their courses and professors' titles. 



B. E. Fernow. 



New York State College 

 of foeestky. 



a final word on discord. 



To The Editor of Science : Mr. Max Meyer, 

 in his criticism a ie\f weeks ago, implied that I 

 had made a mistake in a book review. This, 



