The Senses and the Nervous System 105 



And from a noted German physiologist there came in 

 1938 reports of experiments along the same lines as those 

 just described. Working with a European minnow {Phox- 

 inus laevis) and with one of the common catfishes (Ameiurus 

 nebulosus), he corroborated in general the earlier findings 

 and, with improved techniques and more sensitive methods, 

 proved that the range of hearing was even greater than had 

 been thought. The upper limit of his minnow's ear was at 

 7,000 vibrations per second (A^), while his catfish reached 

 13,000 — almost as high as in human beings. Furthermore, 

 in conditioned response experiments, the minnows showed 

 tone-discriminating ability, intervals as small as. one-half 

 tone being distinguished by the most musically gifted of 

 the subjects! If, without the cochlea, such fine distinctions 

 are possible, what purpose does our beautiful spiral serve? 

 Possibly the quality or timbre of the sound, regardless of its 

 position in the diatonic scale, is what this organ registers j 

 possibly without it the high C in the most gifted soprano's 

 aria would sound no better to us than the same note in a 

 donkey's bray. 



The German investigators also found out that hearing 

 was more acute in those fishes in which the ear is connected 

 in one way or another to the air-bladder, but this matter 

 will be treated in the chapter to be devoted to that organ. 

 Suffice it to say at this point that we have incontrovertible 

 proof that at least certain species of fish, including the cat- 

 fish, minnow, eel, goldfish, and weakfish, do hear. The 

 sacculus with its lagena plays the important part, and this 

 is borne out by analogy with the amphibians. And a con- 

 clusion that we may permit ourselves is that if these species 

 can hear without a spiral cochlea, it is perfectly possible that 

 trout, bass, tarpon, and tuna hear without a spiral cochlea 

 also. 



The question which inevitably arises at this point is, why 



