Purchase of this book includes free trial access to www.million-books.com where you can read more than a million books for free. This is an OCR edition with typos. Excerpt from book: organisms of the sea. "It might be supposed at first thought that these phosphorescent organisms are not observed to emit light during the day because of the pressure of sunlight, and that if taken into a dark room they would be found to phosphoresce just as brilliantly as at night. Such is, however, not the case, not a spark can be elicited from them even by vigorous shaking, so long as there is daylight in the outer world. But if one stands by and watches in the dark room, as twilight is falling outside, although the organisms have been exposed to light all day, one observes the little lamps light up and flash out one by one like coruscating diamonds in the darkness till the whole fish is studded with flashing and disappearing light, a glorious sight in the darkness and stillness. . . . Regularly every evening the lights come out, and as regularly every morning they are extinguished, although all the intervening time the tiny living creatures have been kept in darkness." 36 It should be noted that changes within the body may make a fixed environment act as a stimulus. Animals change in many ways when physical maturity is reached. Thus the queen ant remains quietly in the dark nest while young. On the advent of maturity she leaves the earth, flies toward the light and keeps away from the ground. When fertilized she again seeks the earth, burrows into it and starts a new colony. The rhythm of nature can hardly fail to impress the observer. The revolution about the sun, the ebb and flow of the tides and the waves of light and sound illustrate rhythm in the purely material world. Birth, youth, maturity, old age and death, show the cycle of life. The alternating periods of rest and activity, thepulsations of the heart and the inhalation and expiration of the breath display it i...