Oh. XXII.] CHINA SEA CONFEEVA. 331 



-^because a second blood-red species, T. Hindsii, had been 

 found off the west coast of S. America. It is somewhat 

 singular that both these species should have the charac- 

 teristic red tint — a tint which I have never seen assumed 

 by any of the vast quantities of Trichodesmium which have 

 passed under my notice. 



I saw none of this red appearance in my passage down 

 the Eed Sea, nor any indication whatever of the existence 

 of Trichodesmium therein; but first observed it in the 

 Indian Ocean in lat. 5° N., and long. 70° E., when I entered 

 the remark in my journal that the sea had a dusty appear- 

 ance, as though mjTiads of minute bodies were floating in 

 it — an appearance rendered very distinct when the sun 

 shone upon it. I fancied these motes might be minute 

 animals, which perhaps produced the luminous sparks 

 so often visible at night ; but having succeeded in getting 

 some of the water, I found that the objects in question 

 were little bodies, which under a lens presented the appear- 

 ance of sheaves of minute fibres, constricted m the middle, 

 but loose at the ends, like sheaves of corn in miniature. 

 It was not, however, tOl we were east of Singapore, and 

 fairly in the China Sea, that this peculiar phenomenon be- 

 came visible in aU its remarkable features. Nearly everj^ 

 day, while traversing this sea, more or less of Trichodes- 

 mium was to be seen, and not unfrequently the sea was 

 covered with a thick scum like that which settles upon a 

 stagnant pond, only of a yellowish brown colour. In very 

 calm weather this scum formed a regular, smooth peUicle 

 in the water, thrown up here and there into folds and rugo- 

 sities. Such a scum would sometimes cover the sea more 

 or less for nearly the whole day with little interruption. If, 

 however, a moderate breeze was blowing, and the sea raised. 



