460 THE POPULAR SCIENCE MONTHLY. 



similar to those of my bird, and after having adojited several of the 

 peculiarities which had made ray machine successful. He then suc- 

 ceeded in giving sustained flight to his machine, which we have our- 

 selves seen fly horizontally nearly seven metres, after having been 

 started by a slight impulse from the hand. M. Tatin, also, in 1874, 

 made two very curious artificial birds, vising twisted caoutchouc as a 

 motor. M. Marey has told us that he saw the first named fly in his 

 garden, last November, from eight to ten metres. We have seen 

 the second, nearly identical with our bird, fly in a still more satis- 

 factory manner. 







A MUSEUM EXCHANGE.' 



By Prof. BURT G. WILDER. 



ripHERE are in this country three institutions more or less available 

 JL for the distribution of material for Natural History instruction: 

 the Smithsonian Institution at Washington, District of Columbia ; the 

 (Agassiz) Museum of Comparative Zoology, at Cambridge, Massa- 

 chusetts ; and Prof. Ward's establishment at Rochester, New York. 



The first is especially rich in American forms, the collections of 

 government surveys, and the types of Baird's descriptions. There 

 are many duplicates, but these are required for the elucidation of the 

 extent of variation within the species, so that they are available for 

 exchanges in only a limited degree. 



The peculiar value of the Cambridge Museum comes from the im- 

 mense amount of material fiom all j^arts of the world, upon which 

 zoologists are enabled to pursue extended investigations, either at 

 the museum, or, under certain conditions, elsewhere. 



Agassiz also desired to prepare collections for educational insti- 

 tutions in Massachusetts, and to provide for teachers an opportunity 

 for summer instruction and for the collection of specimens. 



But it is evident that the above-mentioned establishments and 

 arrangements are not yet able to meet a rapidly-growing want of the 

 whole country ; namely, the immediate formation of museums for the 

 illustration of the courses in natural history which are now generally 

 demanded, in not only the colleges and universities (whether real or 

 so called), but also the normal schools, and even those of lower grade. 



Such selected collections need not be either very large or very 

 costly. They should embrace mainly typical forms, but contain also 

 some of the peculiar or aberrant species of each large group. 



It would be well if some one would make out a list of what are 

 desirable in larger or smaller collections. Meantime, the information 



' Presented at the Detroit meeting of the American Association for tlie Advancement 

 of Science. 



