366 



THE POPULAR SCIENCE MONTHLY. 



maux have no kindred on the Eastern Con- 

 tinent. 



As the philosopher of the nineteenth 

 century claims that " in his hands theory 

 is never divorced from fact," we who are 

 not philosophers complain, as we have the 

 right to do, when they fiatly contradict each 

 other and furnish no evidence to fortify 

 their statements. We accept their dicta so 

 long as they agree, but we object to a dic- 

 tum which contradicts another dictum equal- 

 ly respectable. D. A. Hdlett. 



New Toek, May 12, 187T. 



EDIBLE MUSHROOMS. 



To the Editor of the Popular Science Monthly. 



Sir : In the paper on " Mushrooms," etc., 

 in the last number of your Monthly, I think 

 Mr. Julius A. Palmer, Jr., uses the name of 

 *' Dr. Curtis, of South Carolina," for that of 

 the great mycologist, Dr. Moses A. Curtis, 

 of North Carolina, in connection with let- 

 ters written to Mr. Sprague on " Mush- 

 rooms." Whether that is so or not, I am 

 safe in saying that during our late war Dr. 

 Moses A. Curtis wrote a work on "The 

 Edible Fungi of North Carolina," illu.trated 

 with colored drawings by his son (I believe 

 the Rev. Charles Curtis), and this manu- 

 script work is still in existence. It is the 

 result of Dr. Curtis's botanical investiga- 

 tions, as well as of his personal experience, 

 as to which of the mushrooms are fit to eat. 

 Many times, I am told, the good doctor had 

 uncomfortable symptoms after trying a new 

 mushroom, but you may be sure he did not 

 stop until he learned more about it. His re- 

 searches were begun in the war with a view 

 to furnish such information to his people as 

 would enable them to recognize edible 

 mushrooms, and so supplement the poor 

 diet so universal among even the better 

 classes, but I believe he never cared to pub- 

 lish the work. I deem it but justice to 

 the memory of Dr. Curtis to make this 

 statement. Thomas F. Wood. 



"Wilmington, North Carolina, April 80, 1877. 



To the Editor of the Popular Science Monthly. 



Sir : Will you permit a suggestion as to 

 Mr. Herbert Spencer's descriptive term 

 "negatively quantitative," and his specifi- 

 cations under it ? It appears to me to be- 

 long to an undesirable class of definitions, 

 because its defining part consists not only 

 in asserting the absence of something, but 

 in so asserting it as to require just as much 

 the assertion of all the other absences that 

 exist. That is to say, Mr. Spencer's defi- 



nition, and his explanations of it, as cited 

 in the Monthly of March, page 611, appear to 

 me to necessarily imply the following pre- 

 liminary proposition (which I do not think 

 Mr. Spencer meant to imply) : "A definition 

 may consist of a statement that a single 

 quality or characteristic is excluded from 

 the thing defined." Now, of course, a defi- 

 nition, to be a good one, must accomplish 

 two things, neither of which the above is : 

 it must specify the qualities which the thing 

 defined does possess ; and it must exclude 

 not some one other, but all others.. 



Further : is not the term " negatively 

 quantitative " liable to be misunderstood 

 from ambiguity? It seems to me that it 

 may honestly be taken to mean either of 

 the two following : 



1. Being such as to exclude deahng with 

 quantity or quantities. 



2. Being such as to include, so far as it 

 does deal with quantities, only what are 

 called "negative quantities." 



These are, of course, quite different 

 meanings. It appears to me that Mr. Spen- 

 cer applied the former, and that Mr. Halsted. 

 in his communication to you, had in his 

 mind the latter. If so, a misunderstanding 

 was pretty likely. 



I need not explain the benefit of avoid- 

 ing the use for one purpose of terms already 

 employed for another. And as I am a sin- 

 cere admirer of Mr. Spencer, and of his great 

 contributions to the advancement of sound 

 thought, I hope you will not suppose I want 

 to do anything in the way of attacking or 

 fault-finding. F. B. P. 



Boston, April 8, 1877. 



THE HABITAT OF THE GAR-PIKE. 



To the Editor of the Popular Scienpe Monthly. 



Sir : Since the publication, in the May 

 number, of the first part of my article " Gar- 

 Pikes, Old and Young," I have had informa- 

 tion as to the occurrence of Lepidosttus in 

 Black Lake, near Ogdensburg, New York ; 

 in the Patapsco River, Maryland, and in the 

 Edisto, Ashepoo, and Combahee Rivers, 

 South Carolina. 



It being commonly supposed that Lrpi- 

 dosteus is rarely found outside of the Great 

 Lakes or the Mississippi River and its tribu- 

 taries, I shall be much obliged to your 

 readers for any information as to its occur- 

 rence elsewhere. Particularly valuable 

 would be facts as to the time and place of 

 spawning; and the eggs or newly-hatched 

 young are greatly desired. 



B0RT G. Wilder. 



Ithaca, New York, May 10, 1877. 



