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Rotalinse. Large quantities of ooze and white clay, which 
proved to be only the white chalk in different stages of com- 
pression, also came up in the trawl. If the conditions now 
existing at that depth at all resemble those of the time of the 
white chalk, I could readily understand how perfectly sea- 
urchins or molluscs would be preserved if once enclosed in 
this homogeneous substance, to be gradually compressed into 
solid white chalk. 
In one of the hauls taken between Cape May si and Jamaica 
(1,200 fathoms), we obtained the first specimens of Phormosoma 
I had seen alive. I was much astonished to find them, fully 
blown up, hemispherical or globular in shape. This was the 
shape they always took in subsequent hauls, and on several 
occasions, when they were obtained from comparatively shallow 
water, near the 100 fathom line, they came up fully alive and 
retained their globular outline. The alcoholic specimens I had 
seen in the Challenger collections came up as flat as pocket- 
handkerchiefs, from great depths, and were naturally regarded 
as flat sea-urchins, although of course endowed with great mo- 
bility of test. These Echini, with their globular flexible tests, 
recall vividly the Perischoechinidae, with which they have also 
points of resemblance of great interest in the structure of 
their ambulacral and interambulacral plates. 
In the dredgings taken off the south-eastern end of Jamaica, 
we did not bring up anything of great importance. From 
Jamaica we were obliged, owing to the strong trades, to keep 
on towards St. Thomas, without either sounding or trawling, till 
off Porto Rico. During the winter months the trades blow 
sufficiently hard to make dredging and sounding quite uncom- 
fortable on a vessel of the size of the Blake. We had, there- 
fore, no opportunity of adding anything to the hydrography of 
that part of the Caribbean Sea. 
On arriving at St. Thomas’s we made a programme for our 
season's work. This we were fortunate enough to carry out to 
the letter, as far as the dredging and sounding were concerned. 
With the exception of the time required for coaling and over- 
hauling the engine at Martinique and St. Lucia, not a single 
day was lost. Although Lieutenant-Commander Sigsbee, U.S.N., 
did not command the Blake , yet the improvements which were 
made this year in the dredging and sounding apparatus were 
all carried out under his supervision, the vessel having been 
fitted out for sea before he was relieved by Commander J. R. 
Bartlett, U.S.N., who commanded the Blake during this winter. 
It was also my good fortune to find on board the majority of 
the officers with whom I sailed in the winter of 1877-78. We 
thus started under the very best auspices. In the use of the 
improved machinery, suggested by our former cruise, the ex- 
