654 



SCIENCE. 



[N. S. Vol. II. No. 46. 



the tailings, awaiting more perfect methods 

 of treatment. 



Much may be learned from the systematic 

 habits of the astronomer, dividing his work 

 among the several observatories in a spirit 

 of helpful cooperation, and assigning the 

 labor of computation to those who are 

 fitted thus to follow the lead of others. 

 What better service can we do for the Uni- 

 vei'sity student than to set before him some 

 of the problems in mathematical or physical 

 chemistry that require patient toil, and give 

 him the pleasure of assisting in their solu- 

 tion by the use of logarithms and squares ? 

 "What is more practical than to utilize any 

 service he can render ? 



In conclusion, I beg leave to suggest the 

 appointment of a joint committee (repre- 

 senting Sections A, B and C of the Ameri- 

 can Association) to consider the feasibility 

 of sti'iving towards the following ends : 



1 . The compilation of all reliable data of 

 physical chemistry in convenient form for 

 reference, distinguishing those detei-mined 

 directly from those calculated indirectly. 



2. The calculation of empirical formulas, 

 to combine any series of data, when some 

 better form of generalization is not already 

 at hand. 



3. The preparation and use of rational 

 formulas, wherever possible, to deduce the 

 natural constants from series of observa- 

 tions, and to express the conditions that 

 may be expected to hold between observa- 

 tions of different kinds. 



4. The organization of a band of volun- 

 teer compilers and computers from among 

 advanced students, who (with the counsel 

 and aid of their instructors) may assist in 

 the woi-k of compiling data and computing 

 formulas. 



8^° While the time did not seem ripe for 

 the appointment of such committee at the 

 late meeting of the A. A. A. S., the writer 

 would be pleased to receive any further 



suggestions from those interested, regard- 

 ing the points noted above. 



EoBT. B. Waedee. 

 Howard Univeesity, Washington, D. C. 



REMARKS ON SOME RECENT FUNGI EXSIO- 

 CATI. 



It is still a favorite mode among mycolo- 

 gists to distribute exsiccati, or series of 

 specimens of fungi collected from time to 

 time by various persons and in different lo- 

 calities. In times past these exsiccati have 

 served a very useful end in enabling collec- 

 tors to acquaint students with any new dis- 

 coveries, and it has not been unusual to find 

 many new species described in them. Even 

 at the present day this habit prevails to a 

 greater or less extent, and diagnoses of new 

 species frequently occur in these collections. 

 In the writer's mind, however^ the custom, 

 although sanctioned by long usage, is rep- 

 rehensible,especially in those cases in which 

 the species are not also described in some 

 botanical journal. At a period when such 

 journals were few, and when their circula- 

 tion was limited, the distribution of exsic- 

 cati with these new species was j ustifiable ; 

 but now, with the great increase in means 

 of publication and the facilities for illus- 

 tration, the necessity for this has passed 

 away. It is, indeed, questionable whether 

 such species can be regarded as published 

 in the strict sense of the word. Exsiccati 

 are from their very nature ephemeral. 

 They are easily destroyed by insects and 

 other pests. They have no place on the 

 shelves of the library. They are very lim- 

 ited in their circulation, and their limited 

 numbers and relatively high price practi- 

 cally place them beyond the reach of the 

 majority of students. Only a small num- 

 ber of persons, therefore, have access to 

 them, and they must be sought for in the 

 larger herbaria of the country. The ma- 

 jority of botanists are therefore seldom cog- 

 nizant of the new species described in 



