OBJECTIONS TO EVOLUTION 169 



the eyes of spiders. Most spiders have six or eight 

 eyes. 



Some of the Tunicata have ocelli " placed between 

 the oral tentacles." 



Scorpions have six, eight, or twelve simple eyes. 

 Among the Myriapoda, Lithobius Melanops " has 

 twelve large black eyes on either side of the head," 

 while Lithobius rubriceps has fourteen small black 

 eyes on each side. 



Among the Planarida, " Pigment spots, or rudimen- 

 tary eyes, from two to sixteen in number, are often 

 present, and are always placed in the prse-oral region 

 of the body," 



Many insects have two compound eyes, containing 

 from a few facets up to many thousands of facets in 

 each, and they also have three simple eyes on top 

 of the head. The facets in the eyes of insects are 

 six-sided, while those of crustaceons are four-sided. 



Darwin says of compound eyes: "But these 

 organs in the Articulata are so much diversified that 

 Miiller formerly made three main classes of compound 

 eyes with seven subdivisions, besides a fourth main 

 class of aggregated simple eyes." 



The cuttle-fish has the most highly organized and 

 perfect eye found among the invertebrates. It 

 approaches the eyes of vertebrates in structure. 



Finally, in the eyes of vertebrates we find organs of 

 the most wonderful structure and powers. 



The above are some of the many kinds of eyes and 

 eye-spots found in living beings. To enumerate 

 them: There are the eye-spots of microscopic plants, 

 of certain protozoa, of the jelly-fish, of the star-fish, 

 of the sea-urchin, of the Tunicata and the eyes of the 

 pecten in the edge of the mantle, of the snail on 

 stalks, the median eye of Nauplii, which disappears 

 and is followed by two compound eyes, the single eye 



