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THE AMERICAN NATURALIST [Vol. XL 



maintained by many, e. g., Brown. But as Finsch has stated, 

 observations on this point are lacking, and we ourselves observed 

 nothing of the sort. It is not known by the old Queensland dugong 

 fishers to enter brackish water, and that it seeks the fresh water 

 of the river itself is out of the question. 



During the day the dugong remains in the deeper waters of 

 the outer ocean and only at night comes in through the channels 

 previously mentioned to feed in the bay. This observation is 

 corroborated by those of Klunzinger in the Red Sea, and by the 

 statements of Semon and Finsch. With regard to its appear- 

 ance at night, Klunzinger makes a noteworthy statement based 

 on the accounts of the Bedouins. According to them the dugong 

 is recognized at night not only by its "blow" and by the phos- 

 phorescence of the disturbed water, but also, they asserted, by 

 three shining spots on the back, a fact of which he was repeat- 

 edly assured but which he found it difficult to believe. Krauss 

 attributed this to the luminosity of the sea, but by Brehm it is 

 explained as due to the sparkling in three places of the water 

 that is disturbed in swimming, and thus made luminous. These 

 three places would correspond well to the rounded ripples that 

 would be made by the head, the middle of the back, and the cau- 

 dal fin. Langkavel also cites Klunzinger's statement. No such 

 phenomenon was observed in the Australian waters, a fact that 

 may have been in part due to the slight degree of phosphores- 

 cence of the surface water at that time of the year (the Australian 

 wmter). However, in spite of the bright light of the tropical sea, 

 It is highly probable that this is a faulty observation, and untrue 

 of the dugong. For as it swims, its head first appears above 

 water to take breath, rarely the back follows, while the tail is 



vements 



might very well produce a 

 more or less clear flashing when the water is strongly phosphor- 

 escent. but it would seem quite as impossible to identify the ani- 

 mal by this as to tell it by the noise it makes in breathing. Dexler 

 lunted the animals in waters inhabited by both dugongs and 

 dolphins, an<l ui the tropical nights made careful observations 

 for many hours while lying in wait at the nets in their pursuit. 

 At no time, however, was it possible to distinguish the two by their 

 resounding "blow" though often they were extremely near at 



