3 i2 POPULAR SCIENCE MONTHLY 



I recall the living IcMhyophis, the curious burrowing salamander, 

 which I once had the opportunity of observing in Ceylon. This is 

 surprisingly like a worm in many regards, yet a mimic it can not be, 

 since it could derive no profit from the resemblance, the worm being 

 infinitely less protected than itself. If any mimicry could exist in this 

 case it is clearly in the opposite direction, the worm mimicking the 

 salamander, but this possibility is precluded since the mimicking form 

 is infinitely more plentiful than the mimicked, and, most significant, 

 neither form is apt to expose itself in a light where the resemblance 

 would have any value. None the less the mutual resemblance is quite 

 striking — in shape, proportions, size, color, annulation, movements, 

 position of vent, etc. Yet we can only interpret it as due to parallelism. 

 And if this is the case, may not parallelism, i. e., similarity in struc- 

 tures due to similarity in habits, not mere accidental resemblance, be 

 taken as a further clanger in interpretation. 



For the rest we may query, as others have done, whether the 

 importance of protective coloration and mimicry may not be still 

 further diminished when we eliminate our anthropomorphic conception 

 of the senses of the lower animals. For we may reasonably harbor the 

 suspicion that colors and patterns, which to man seem protective, are 

 by no means as valuable as protection against the keener and more 

 specialized visual impressions of the lower animals. For just as 

 " scent " perception in certain invertebrates, as in various moths, is 

 immeasurably refined, far more so than we are in the habit of con- 

 ceiving the scent-sense, so also there may have been developed a special 

 sense for detecting- the most subtle differences in color, texture, form 

 in those animals which prey upon mimetic and protectively colored 

 forms. Indeed, such a view is the less unreasonable when one con- 

 siders the condition of the optic centers and end organs in those verte- 

 brates, teleosts. reptiles, amphibia, birds, which have most to do with 

 creatures in which protective coloration and mimicry is supposed to 

 occur most abundantly. And it is not beyond the pale of possibility 

 that the predatory forms have evolved habits in connection with sense- 

 organs which would cause them to distinguish more promptly the pro- 

 tected forms than those having bright and obvious colors. It is in 

 this direction that we have need of close observation and critical 

 experiment. 



