178 Cruise 0/ the "Alert." 



These rods, which seemed to represent the adult plant, measured 

 uwu '"'^''' '" width. On careful examination of many specimens, 

 some filaments were observed, portions of which seemed to have 

 undergone a sort of varicose enlargement, having a width two or 

 three times that of the normal filaments. These propagating 

 filaments (if I am right in so calling them) were invested by a 

 delicate tubular membrane, and were filled with a granular semi- 

 transparent matter, in which were imbedded a number of discoid 

 bodies which were being discharged one by one from the ruptured 

 extremity of the tube. These bodies measured -^^qj^ of an inch 

 in diameter : when viewed edgewise they presented a lozenge- 

 shaped appearance, and they were devoid of cilirc or stri.e. A jar 

 full of the sea-water was put by until the following day, when it 

 was found that the confcrvoid matter had all risen to the surface, 

 forming a thick scum of a dull green colour, while the underlying 

 water was of a pale purple colour, resembling the tint produced 

 by a weak solution of permanganate of potash. 



From the 24th to the 29th of November, during which time 

 the ship traversed a distance of three hundred miles, we were 

 surrounded by these organisms ; during the first three days the 

 large patches were frequently in sight, and for the rest of the 

 time the sea presented a dusty appearance, from the presence of 

 finely-divided particles. On the evening of the 25th an unusually 

 dense patch was sighted, and mistaken for a reef, being reported 

 as such by the look-out man aloft. 



On the 28th November I encountered among the proceeds of 

 the tow-net another minute alga, of quite a different appearance 

 from that just described. It was composed of vermiform rods 

 To'oo '""^^^ '" width, and breaking up into cylindrical segmcHts 

 with biconcave ends. 



We returned to Levuka on the 4th of December, and stayed 

 in harbour for ten days. At this time we had dismal wet weather, 

 and consequently little was done in the way of exploration. I 

 received a visit Uom a Mr. IJojd of W'aidou, a colonist, who has 



