slight snapping noises produced by the sudden 

 closings of the little lower jaw — which are sup- 

 posed to represent speech, are not conscious or pur- 

 posive utterances, but they are secondary effects of 

 a primary but undecipherable cause also mani- 

 fested in a series of slight trembling movements of 

 the entire body, a quivering which usually makes 

 its appearance at some time just preceding the 

 animal's death. This quivering may occur within a 

 few hours or a few weeks of the time that the sea- 

 horse expires; but, so far as my tanks bear witness, 

 these paroxysms are invariably the prelude to the 

 end. 



Notwithstanding that the real mechanism of 

 this pathological condition is yet unknown, there 

 is reason to believe that it is in some way connected 

 with the functioning of the air bladder, the organ 

 which stabilizes the buoyancy of the sea-horse and 

 enables it to maintain its characteristic upright po- 

 sition in the water. The air bladder, comparatively 

 larger in the liippocampids than in most other 

 fishes, is distended with gas, the quantity of which 

 is so nicely adjusted that the entire body of the 

 individual is, in short, a very sensitive hydrostatic 

 apparatus. So delicate is this adjustment that if a 



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