1344 BULLETIN OF THE BUREAU OF FISHERIES. 



other vertebrates and the primary divisions within the class, might well be 

 introduced here. 



The systematic series of fishes is to form the principal portion of the col- 

 lection and is to include typical examples of the various subclasses and orders. 

 It should not be too large and it should as a rule be confined to the more char- 

 acteristic forms. The object of this series is to show the main divisions of fishes 

 and give the observer an idea of their general appearance. To multiply forms 

 and individuals would therefore be confusing and defeat the very object in view. 



In selecting specimens to represent the various groups, preference should -be 

 given to the more characteristic and better-known species and, so far as possible, 

 to species common in the vicinity " where the exhibit is to be displayed. The 

 more common the species the more familiar is it to the observer, the more readily 

 will he associate it with the fact illustrated, and the more forcibly will that fact 

 be impressed upon him. The educational value of a specimen does not depend 

 on its rarity but on the clearness with which it shows the fact it is intended to 

 illustrate. 



The larger extinct groups should be represented both by their fossil remains 

 and by models or pictures, and important or readily obtainable fossil forms 

 should be introduced in their proper places among existing species. In no way 

 save by the use of fossils can a proper idea be given of the relationships of various 

 groups and of their relative importance at the present time and during past 

 geologic history. 



As an adjunct to the systematic series there should be groups or pictures 

 illustrating important or interesting points in the habits of fishes, such as the 

 sargassum fish and stickleback with their "nests," the sunfish and its nest, the 

 remora clinging to a shark, etc. 



Small series or assemblages of fishes peculiar to certain localities or habitats 

 could be introduced to advantage ; thus a series of deep-sea forms would empha- 

 size the peculiarities of the abyssal fauna and the remarkable modifications 

 for life at great depths. Examples of deep-sea fishes should also be shown in 

 their respective groups to illustrate the facts that the deep-sea fauna has been 

 derived from that of the shallower seas and that resemblances that exist between 

 them are largely due to adaptations toward one end — life in the depths of the sea. 



One of these "supplementary series" might be devoted to the brilliant 

 fishes of tropical waters, attention being called to the contrast they offer to the 

 modest colored but important food fishes of temperate regions. In such "sup- 



a For example, a museum located near the Atlantic or Pacific coast should draw for its examples, so 

 far as possible, upon the salt water fishes, while an inland museum should select as many examples as 

 possible from the lakes and rivers. This naturally would be practicable only to a limited extent, owing 

 to the fact that even the most scanty representation of the principal groups of fishes calls for many 

 species. 



