THE VOYAGE OF H.M.S. CHALLENGER. 
Station 100 . 
I >RT.ANISMS PROM 
Surface- Nuts. 
At 1.30 p.m. shortened and furled sails, and got up steam to sound. Sounded in 
_ ! .5 ft thorns. Attached dingey by line, and sent cutter away to try current, which was 
running it the surface at the rate of half a mile per hour eastward. At 3 p.m. obtained 
serial temperatures down to 1500 fathoms. The carbonic acid was determined in the 
•■'Urface water, and amounted to 43 - 2 milligrammes per litre. At 4.30 p.m. picked up line 
from dingey ; line carried away in heaving in, and a thermometer was lost. At 5 p.m. 
utter returned. At 6.20 p.m. completed temperature observations, and at 6.30 p.m. 
made all plain sail. At night sea phosphorescent. 
Distance at noon from St. Paul’s Rocks, 879 miles. Made good 145 miles. Amount 
of current 28 miles, direction S. 45° E. 
Surface Organisms. — The following species are recorded from the surface in this 
locality : — 
Schizopoda (Sars, Zool. pt. 37). 
Euphausia pelludda, Dana. 
„ gracilis, Dana. 
Ni DIBRAMHIATA (Bcrgll, Zool. pt. 26). 
Ph ylliroe atlantica, Bergli. 
Acura pelagica, Adams. 
Pthropoda (Pelseneer, Zool. pt. 65). 
Cavolinia uncinata (Rang). 
Tunicata (Herdman, Zool. pt. 76). 
Pyrosoma atlanticum , P^ron. 
„ giganteum, Lesueur. 
Fishes (Gunther, Zool. pt. 78). 
Young Pleuronectids. 
Leptocephalus morrisii (young). 
Will- mocs-Suhm writes: “The sea was more luminous than ever, due chiefly to 
ill* presence of innumerable specimens of Pyrocystis, which made the water quite 
yellow. Foraminifera were also very abundant, and Peridinium ( tripos and another 
-jh . ks), which is known to cause phosphorescence when in great quantities, was present. 
Cope pods, Stpiillerichthus, and various other Crustacea, were taken in the tow-net, 
n . ; it quite slimy when hauled in. I think that Corycseus , Acura, Pneumonod erma, 
C -rmr' l<i, and the Pleuronectids do not belong to the North Atlantic surface-fauna, but 
‘ In i w< have now entered within the limits of the South Atlantic fauna.” 
August 16, 1873. 
Th« phosphorescence was not so brilliant, and the tow-net procured only some 
J' fr< ' /.-f< •, Fonminifera, and a few Crustacea. Some large sea-birds with white 
j lum.igc (Sula fusca) were soaring about, keeping very close to the water ; they were 
not following the ship, but fishing. 
