18^2.] MICROSCOPICAL JOURNAL. 163 



interpietation. Small as this book seems, it is actually only 

 half as big as it looks, every second page being a duplicate, 

 repeating in French the substance of the opposite page in Dutch. 

 In this very practical way the little book appeals to a greatly 

 enlarged circle of readers. 



Among the larger exhibits were several works by Dr. Wm. 

 Rehrens ; and seven volumes by Dr. J. Pelletan, of Paris, in ad- 

 dition to the fifteen volumes of his '■'■ Journal de jMicrograpic^'' 

 the whole representing an extraordinary amount of able work. 



Dr. Henri Van Heurck exhibited the four editions of his trea- 

 tise on the microscope, the two grand volumes of his " Synopsis 

 dcs I)iatoj?iccs de Bclgiqtie" with its atlas of 3,100 figures, and 

 seventeen pamphlets. These, in connection with his large col- 

 lection of interesting antique microscopes, his apparatus for 

 electric lighting, for photomicrography, for micrometric ruling, 

 etc., his unsurpassed photomicrograms of diatoms and other test 

 objects, and his preparations of type specimens of the diatoms of 

 Belgium, on which his " synopsis" was founded, rendered him 

 by far the most important exhibitor at the exposition. The fourth 

 edition of his book on the mici'oscope was brought out on this 

 occasion, and it was so freely rewritten from the former edi- 

 tions as to be essentially a new book. The modern optics and 

 present construction of the microscope are adequately discussed, 

 the latter, naturall}', most fully from continental experience. The 

 general management of the microscope and preparation of objects 

 is included, photomicrography and the staining and slicing of 

 tissues having prominence according to the fashion of the time ; 

 but the application of the microscope to the study of plants, and 

 especially of diatoms, is omitted, to appear as a special volume 

 hereafter. Desiring to make the present volume worthy and able 

 to serve as a '■'' livre de luxe" commemorative of the occasion 

 without the natural impediment of a proportionally high cost, the 

 accomplished author secured its publication In a grand volume at 

 his own expense, and had it sold at a price that could scarcely be 

 believed to cover the cost of printing. Even to those fortunate 

 enough to have received the beautiful "diploma of honor," this 

 souvenir volume by Dr. Van Heurck will be second to nothing 

 as a keepsake of the Antwerp Exjoosition. 



EDITORIAL. 



Priority in Giving Scientific Names. — Much stress has been 

 put upon this topic because serious confusion has been caused in 

 many branches of science by two or more scientists putting dif- 

 ferent names upon the same form. In order that confusion may 

 be avoided it has been generally held that when one proposes a 

 new name, he shall give it and the description reasonable pub- 



