No. 469] 



BIOLOGY OF THE DUGONG 



63 



that the eye Hds as in case of the whales cannot be opened nor 

 approximated. The copious secretion of the conjunctival sac 

 has already been mentioned. In our captive the strinjj of slime 

 was of the consistency of the white of an egg, was as thick as 

 one's finger, and flowed over the entire eye and down to the 

 ground. That this secretion might be due to the irritation caused 

 by the atmospheric air or the unaccustomed light immediately 

 suggested itself, but in all the animals taken the secretion was 

 similar without any difference in regard to mass, thickness, con- 

 sistency, nor transparency and thus possessed properties not 

 present in a catarrhal flow. The corneal reflex was easy to demon- 

 strate and the eye lids were always held open. 



The eyes of the dugongs that were dead when taken, were 

 always injured even if they had hung in the nets onlv six or eight 

 hours. In such cases there were uneven scratches with finely 



brana descemeti. Tiny were alwavs interior To the poles of the 

 cornea, which lay free in dcalh. The lens nsnally showed star- 

 more pronounced the lonutM- the Ixxlv was allowed to remain in 

 the water. These spots were doubiUvs-^ plieiionieiia incident to 

 death, 'llie secretion of so great a (piantitv of slimy viscous 



the surface of the eye from injuries from the sea water or its platd<- 

 ton fauna. If the slimy covering fails dien the bulb of the eve 

 is without protection. In this way are caused the scratches above 

 mentioned, of whose traumatic nature there can b(> no .lonht. 



abraded iLt they bleed freely. 



The presence of a slimy protective coat for tiie vyv lia> al>o 

 })e<-n demoiiMiaied for the whales, only in them it i^ not watery 

 and imicoii> i,, the dugong, but oilv for otherwise it would he 

 too easily washed away bv tlie sea water (Putter, :()3, p. .">70>. 

 Thus in the Cetacea a clianirc of function has taken place in the 

 glands of the vyv as an a(la|)tation to the conditions of a(]|uatic 

 life, and their products are likewise changed. 



The copious secretion of mucus from the dugong's eye has 

 long been known to many of the islanders of the Malay archi- 



