300 ANNUAL OF SCIENTIFIC DISCOVERY. 



in which the flexor tendons of the fingers exceed the flexor ten- 

 dons above the wrist by 14.4 per cent. The bearing of the fore- 

 going results in the habits of locomotion of the several animals 

 will suggest themselves at once to naturalists who have carefully 

 studied those habits. I shall merely add that the subject admits 

 of being carried into the details of the separate or combined 

 actions of the several fingers and toes, and that the habits of 

 various kinds of monkeys in the use of certain combinations of 

 fingers or toes may be explained satisfactorily by the minute 

 study of the arrangement and several strengths of the various 

 flexor tendons distributed to the fingers or toes. Nature. 



THE VOLCANO FISH. 



A paper having appeared some time since in a contemporary, 

 from the pen of the Rev. W. W. Spicer, in which the phenomenon 

 of the expulsion of fish from volcanoes was spoken of as strange 

 and astounding, and the idea being conveyed that the fish must 

 have " lived in the line of fire " before being expelled, Mr. Scrope, 

 F.R.S., writes to "Scientific Opinion," February 23, as follows: 

 * ' This sensational version of a very simple fact is one only of sev- 

 eral which, on the authority of ' the great Prussian traveller,' have 

 been repeated by compilers of treatises on volcanic phenomena. 

 The simple fact, I conceive, is that the fish in question lived in the 

 open air in crater lakes, such as are frequently found at the sum- 

 mit of trachytic volcanoes, for the reason that the fine ash, which 

 is usually the last product of their eruptions, and therefore forms 

 the lining of their craters, is very retentive of moisture, and con- 

 sequently occasions the production of lakes at the bottoms of these 

 hollows. Of course, in these lakes the same kind of fish will prob- 

 ably be found as, by Mr. Spicer's own statement, are met with in 

 other lakes at an almost equal elevation on the outer sides of these 

 very volcanoes." 



CHANGES IN FISHES. 



In the "American Naturalist," Charles C. Abbott, M.D., gives 

 some account of the changes in the fishes of New Jersey within a 

 few years. A slight local disturbance sometimes quite alters the 

 fauna. Thus, in 1867, a small, never-failing brook, emptying into 

 the Assumpink, was populated by chubs, dace, and minnows. In 

 July a heavy, sudden fall of rain caused a rise of water, but did 

 not alter the brook enough to attract the attention of those who 

 lived near it. After the subsidence of the water not one of these 

 fish could be found there, while their place was taken by roach, 

 mullets, and red-fins, which are now abundant, while not a chub 

 can be found. 



Dr. Abbott mentions several fishes that were not inhabitants of the 

 New Jersey streams 25 years ago, which are now quite abundant ; 

 and he is greatly at a loss to imagine how they can have reached 

 these streams. He mentions the interesting case of the gizzard 

 shad, which is sometimes carried by freshets into inland streams 



