320 LESSONS FROM NATURE. [CHAP. X. 



But, indeed, what are the grounds on which Mr. Darwin 

 builds as regards birds? As before said, they are &quot;display&quot; 

 by the males, their &quot; greater brilliancy and ornamentation,&quot; 

 and the &quot; occasional preference &quot; by females in confinement 

 for particular males. What value is there in this founda 

 tion for such a superstructure ? In the first place, in insects, 

 e.g., butterflies, we have often many brilliant males crowding 

 in pursuit of a single female. Yet, as Mr. Wallace justly 

 observes, &quot; Surely the male who finally obtains the female 

 will be either the most vigorous, or the strongest-winged, or 

 the most patient the one who tires out or beats off the 

 rest.&quot; Similarly in birds strength and perseverance will, no 

 doubt, generally reward the suitor possessing those qualities. 

 Doubtless, also, this will generally be the most beautiful or 

 most melodious ; but this will simply be because extra 

 beauty of plumage, or of song, will accompany supereminent 

 vigour of constitution and fulness of vitality. What has 

 been before said as to the fierce combats of cock-birds must 

 be borne in mind. 



But that internal spontaneous powers are sufficient to 

 its sum- produce all the most varied or bizarre sexual cha- 

 ciency. racters which any birds exhibit is actually demon 

 strated by the class of insects, especially caterpillars, which 

 from their sexless undeveloped state can have nothing to do 

 with the kind of selection Mr. Darwin advocates. Yet 

 amongst caterpillars we not only find some ornamented with 

 spots, bands, stripes, and curious patterns, &quot; perfectly definite 

 in character and of the most brilliantly contrasted hues. We 

 have also many ornamental appendages; beautiful fleshy 

 tubercles or tentacles, hard spines, beautifully coloured hairs 

 arranged in tufts, brushes, starry clusters, or long pencils, 

 and horns on the head and tail, either single or double, 

 pointed or clubbed.&quot; Mr. Wallace adds : &quot; Now if all these 

 beautiful and varied ornaments can be produced and ren 

 dered constant in each species by some unknown cause quite 

 independent of sexual selection, why cannot the same cause 

 produce the colours and many of the ornaments of perfect 



