PARKER — THE FLORIDA MANATEE 
135 
longer it breathes at the surface^ and the more breaths it takes while 
breathing. A small manatee, less than 2 meters long, had an average 
breathing period of 49 seconds during which it averaged 1.7— breaths. 
A large manatee, three meters long, had an average breathing period 
of 1 minute and 17+ seconds during which it averaged 2.6 breaths. 
The small manatee had an average submergence period of 4 minutes 
and 37— seconds with a maximum of 9 minutes and 30 seconds. The 
large one had an average submergence period of 12 minutes and 1 — 
seconds with a maximum of 16 minutes and 20 seconds. These sub- 
mergence periods far exceed those of diving birds and terrestrial mam- 
mals, but are not so long as those of cetaceans. 
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Andrews, R. C. 1916. Whale Hunting with Gun and Camera. New York, 
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Pick, F. K. 1907. Zur feineren Anatomie der Lunge von Halicore dugong. 
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Zoological Laboratory^ Harvard University, Cambridge, Massachusetts. 
