134 
REPORT— 1847 . 
atralus; a, central medulla of areolar structure; 1,1,pillars of first* 
innermost growth; 2,2, pillars of second layer; d, extremity of first- 
formed spine; c, extremity of second layer;/, g, h, i, extremitiej of 
third, fourth, fifth and sixth layers; It c, line of sertion across huo; 
kl, line of section across middle. Magnified 7 diam. 112,113).- 
Fig. 74. Portion of transverse section of stem of pMtamviitet BriartMt 
Magnified 20 diani. 120)., — Fig. 75. Portion of transverse scctioRol 
stem of (species unknown). Magnified 25 diam. ISO) 
j section of stem o( Pentacrinm Captl 
Medusa. Magnified 15 diam. 120)_Fig. 77. Portion of tlieettcnal 
part ol the same section more enlarged. Magnified 150 dim (§ ISP) 
Flate aX. Fig. 78. Section of the siiperfirioJ layer of llie shell of 0^ 
parallel to the surface, showing the reticulated appearance, and the pa- 
pilkry elevations of the subjacent layer. Magnified 75 diam. (§ liTv 
rig. 79. 1 ortion of the samo section rimre eulai^ed, shovini da 
which the layer is composed. Magnified 400 diaa 
(.§124). Fig. SO. Portion of transverse section of claw of Crab,DfafiB 
extremity, showing the fibrous appearance which passes in a radiatuit 
manner from oun surface to the other j and the parallel lines imlicalivi 
0 successive growths. Magnified 50 diam. (§ lilS).—Fig. 81. Porliott 
ot the same section more enlarged, showing that the fibrous appe»^ 
ance is given by radiating tubuli. Mugoified 400 diam. (§ 125). 
;Zn Ti '^hewell, D.D. and Sir James C. 
ZLni of an Expedition for the purpose of 
plehng our knowledge qf the Tides. 
t^hrphmnomeS possess of the tides, looking at the connexi 
at present and surface of the ocean, is extremely impi 
any finite time l.v finniplcted in any material degr 
objects will aiimilv 'yhit'h voyages maiiily directed to i 
waters of the t-oasts and islands which surround or bred 
'“""Of 
the time of tide on the 
with the rise anil fall of i^^aland ; but cannot connect liu 
centre of the ocean We L ^ ° j coasts of the smaller islands« 
land; but cannot trace on the eastern coast of 
coast of China,_thoutrli PhilippuJ^ ‘ 
ago supply a valuahlo^ i r.- ** °^®®‘‘''^bonn of Admiral Liiikemadcai^’^) 
of the fhlltL o knowledge on this subject. The « 
Observations made ''‘lands of the Indian Sea is iikevrise uokui 
little likely to sunnlv tl aiatnly guided by other purposes, ap: 
»i.h »■ our knovrIedV ; for'rvrn rbena 
connected w’ith eurli «tJ ^ ''**'^^8 at. detached places, they arc » 
that while w ar^S,.^ I'laoi 
sl'ull ever he abb. ll n v "" '‘kance for our tidal kno*)ed^> 
Pacific does or does 'T‘ xvhetlier the tide-wave m 
p out on purpose to observe the tides would very soon aa 
