tions of chromatic contrasts; and during the mat- 

 ing season, the affectation of conspicuous colora- 

 tion is most marked, particularly among the males. 

 As a rule, however, Loligo, unless under sexual in- 

 fluences or strong emotional stress, remains for the 

 most part pallid. Its prevailing color is a peculiar 

 pearly paleness which confers upon it a translucent 

 appearance. 



As may be suspected, the sight of the squid is 

 keen. The fixed forbidding stare which distin- 

 guishes its large eyes, is really the result of a 

 marvelous adaptation in so lowly a mechanism of 

 sight. Notwithstanding their seeming structural 

 likeness, the eyes of this animal bear but a close 

 accidental resemblance to those of backboned crea- 

 tures. They are lidless, though they have a lens, 

 transparent cornea, and retina; but the latter, lin- 

 ing the eye-cavity, is not turned inside out, as in 

 the case of vertebrates — it receives the light 

 directly. 



For purely protective purposes, for concealment 

 from, and the confusing of its enemies, Loligo 

 relies on its ink bag. The duct of this organ opens 

 into the intestine near the vent. When the squid 

 is startled or takes alarm, it ejects through its 



[339] 



