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I

I

Organic Siliceous Hcmis in t LaKe

§1

Bv A. H. MACKAY.

[FiaiM THi:('A\AI>IAN I'lECMlUi "F SCIENCE. VoL. 1. No. 4.0CT.. IsS.",.]

• t

■ • • ■ • • «

. * * ■ * .

> It I

111 *

VII. OHCAXi.: SiMCKOUS RkmaIXS IX THE LaKE DEPOSITS

OF Nova Scotia,

i!v A. M. MacKav, I'u'toi; Acadkmv, N. S.
The silicc.„us .Jcpusits in tlir lakes referred to are, fir.t aud
Qiost abundantly, of vegetal.U. nriuin, consisting of the ex<,ui!sitely

Hcndptured e,.ll-walls<.ftl.euniccilular plants, con^^titutino- theorder
Ihatonwaa : and, secHnlly. ..f animal on>in. consi>t^in..' of the
..pieulrs whu-h H.rni th,. sk.l.tons ..I' that group of the fresh-water
sponges k'nown a.^ S/»>,i(ji//i/iu.

''^''*' '"^-^^^f^-^"' 'ft'H- ehara.tev r,f tlu^ lake deposits of Nova

Sootn. has nniy i, en cuimuieod and much is yet expected to be
brought to iigir, The ..xploratinns made during the last two
summ.rs uudude a la,-e nnnd.r of lakes throughout the province
jaryn.gtron. five n,il, > in length to less than one half of a mile, and
from KiO fe.t in deptl. of water (o that of only six or seven
Deposits of.ume nf th. I.uger lak.s have been examined, but no
systematic survey orrhem has yet been made.

. • •• . • . • •

* ***** •.•*• •.• ■ ■ a

*.*«:•: :,.*••: .•* ••* : .•.••• .«.

** *• . . *,* • , .' ... •; »«♦*,.• .
* * •• ••• ..' .... *,•«•• ' •• •*•,..
**• *... *•*•. *,' *.'..: •••..: •,•

*•• . .• •*, .> **
*.. ....*.,, .

... ,.,
.: • *

> O • . . . A . .J
. * • . . .*

Orcf(UK'!c Sil/rciui.s RcniHiiis.

L';:7

Tlic's*! (I(!|M its may lif loiiulily classilicd as I'oUdws : —

First J I'arthy muds.

Srri)n<fh/, black oi' hniwtiisli slimy tiimls.

ThlnJfi/, whitish silictcmis muds, consist itij; m-arly entirely (il'tlic
cell walls of'th(MiiatoinMce;o and the spicules of fresh-watiT sjion^es,
which are lliuii 1 ti» he jirescnt in class(\s /list and si mm/ n\>i\
althuuj;!) in less comiKirative ahundance.

These three classes, dI" course, shade oil" into caeli other with-
out :iny distinct line of dcmarkatiou.

In the first class there is a variable (juantity (»!' fine sand or
clay introduced in times of Ireshets when the water becomes dis-
colored from the earthy matter Ixtrne into it. Deposits ol' this
class abound in lakes into which lari;t'. streams that readily be-
<-<ime turbid flow; and liny form more rapidly, it is presumed,
than tliosc^ of the other classes. Soundinirs in the upper portiotis
of thr li.icliabrr, (iaiden of Kden, Forbes, A ins lie and (Jrarid
Lakes, for instance, briuLi up inaterial of this class, all ab(uindini^;
to some extent with <liatnm valves ami s])oni:»! spicules. The
tlepths of these a<'('umuIations otir primitiv(! boriuu,- apparatus
would not allow us to fathom.

The second class (d'de|tosits is found in abundance in lakes fed
by small stri'ams in the l()rest. Tii ('aider and iMacKay liakes,
Pictou County, the fctrmer beinj;- a full mile in lenuth, the water in
no plac(! appears to hv o\{'V 1) or 10 feet \n depth, the average
being 5 or (I feet. Tn the central portions of these; p(»nds a pole
was driven down by the hand from a raft t^) the depth ol' jJO feet
without striking hard bottom. Nearer the margin, the l)orer
after passing through this deposit, generally took up a stiff clay,
which has als(» been found underlying some peat swamps in the
neighlxtrhood. Tn some ol' tliese swamps analysis lias shown a
large percentage of tlu; incondmstible residue to be comjtosed of
diatomacecuis and sponge remaiiis, thus demonstrating their lacus-
trin(! «u-igin. When the hard l)ott(»m of the above-named and
oth(!r lakes was found to be undulating, the light slimy diatoma-
ecous mud was found to be deej»est in the dej)ressions, — tin; nnid
surface being more conffu'mable to the surbice of the water tlian
to the surface of its bed. In MacLean J>ake, less extensive but
nearly iiO feet deep, the same characters ol' the bed of the deposit
wer(! observe<l. In most of the other lakes, soundings, but no

m

238

Onjdnic SUiccirus Ri/if tains.

borings through thu deposits, were made. The typical mud of
thiH clans in <fonovally of some .shade of a dark grey -brown color,
having aome times nearly the couwintenoe of a very tremulouw jelly,
but paHty to the touch. Some specimenH of this, dried so as to be
so firm as to retain a moulded form, contracted to one tenth of its
volume when perfectly dried, nearly 50 per cent, of which was
estimated to be organic silica. While pieces of decaying W0(kI,
leaves, mosses, etc., are found in this material, its carlxmaceous
organic matter appears to have been to a great extent of algoid
origin. The wat^TS of these lakes are gejierally (colored by the
presence of organic matter in .solution.

The third class of deposits has not been observed in such abun-
dance as the other cl'.is.st!.s. In many cases it may have been formed
i'rom material of the second class, as is suggested by the deposits
often shading oif into each other in th(! same body of water. For
instance, in Ma(;intosh Lake, someof the purest white material did
not come from the greatest depth of the water, but from the
vicinity of shallows, between an i.sland and the mainland. A
gentle motion of the water from an exposed side of the lake is
produced by the wind over this flat, and the deposit alluded to is
iunnediately to the windward of the said flat. This suggests the
hypothesis that the change from the slimy mud to the purer siliceous
deposit may have been, at least partly, due to the solvent action
of the water on the decaying vegetable material. This solvent
action has been plainly demonstrated to exist by the analysis of
the waters of the lakes which supply the city of Halifax with
water, made by George Lawson, professor of Chemistry in Dal-
housie College and University. The waters of Long Lake, the
largest and liighestof the series, was conducted for a time through
the lower Chain Lakes, in which there is a large deposit of diato-
mac/cous slime. The analysis gave 2.13 grains of organic matter
per gallon in the water of Long Lake, and 2.08 in that of the
lower Chain Lake. This shows that each gallon of water may
have dissolved out of the Chain Lakes about half a grain ol"
vegetable matter.

Those lakes, so far as observed, which lie in the midst of granite
drift, and have clear water, have also purer silieious deposits, the
percentage of silica in the dried material a})proxinuitiug in some
uses to betweeu 90 ami 100. Folly Lake is an instance in which

()i(Hin'ii) Sil'"'t'i>'i.'< Jhnid'nis.

230

lie

niiii'li iiiiit('ii:il nl" \\\'\ti kind is sul>iii(ri;o(l, and JU'iir an afflui-nt
of MaiiH-y HivtT is ii ixood cxiinijile of a do}K)sit. wlii»'li is ik^w
left liii^li and <lry.

Tlif liTcatiM- |ir()j)i)rti<tn of this siliwoiis niatrrial is niadc iij)
i>f till- frustulcsor »'})i<lc,rins of about, one liundri'd sjtcrit's ol" tlic
diatonnu^c.'v. Tiic followini; have boon pr(»visionally determined
by eoniparisoji with the mounted types of Mt)ller. {\w. plates
of Schmidt's Atlas. Van ll(>urek's Atlas witli :}.0()() fiirures ..f
Belgian forms, liijures and descriptions by Hrun of (jeneva in
his " Diatomdes des Alpes et du Jura," and tlie deseriittioiis of
RahtMih(»rst in his '' Flora Kurop.'ua Al,!i;arum A(|a;i', Duleis et
Snbmarinai.''

1. CoeeoiM'is pcibculus, Khr

2. C. plaoeiitnla, Ehr.

3. CM)ii(i)lKiiieina iieiunitsatuiii, Khr.

4. " '* rnr . (^ordimtuin, Ktz.
r>. "■ " rar . laticcnM, FJn

Ci. (!. cristaliini, luilf's.

7. (i. iznicile rar. iiavicMiloidis. (irun.

5. (}. al>l>reviatnMi, A(/.
It. (i. capitatniii, Khr.

10. (}. jiiti'icMtMin, Kfz.

11. (i. eistula, Jlcmprr.

12. Kpitliciiiia turi^iila, FJn.
i;{. K. i^ibha, /<;/(/•.

14. " " rnr. parailfla. (inin.

15. Vj. ar!j;us, Ehr.

IC). Iliiiiaiitidium arcus, Fjhr.
17. " " rar- inajns, W. Sm.

IS. "■ " rar. tciielluni. <f'iin.

1!). 11. f'onnica, Khr.

20. II. jieetiriale, Ktz.

21. " " oar. vetitrieosuin, Grun.

22. " " var. minus, Ktz.

2;^. " " rar. undulatain, Rn'fs.

24. U. soloirolii, Kfz.

25. H. bidens, W. Sm.

2r». " " var. diodon, Khr.

27 H- prieruptum rar. intlatuui, Grun.

28 H. polyodon, }irn7i.

29. H. poiydentuluin, Rrvn.

30. Amphora ovabs. Ktz.

31. A. afiinis, Ktz.

240

Oiyiuiir Sfflicniis lii'itudnfi.

'.VI

:!l
;!r.
.Id

;i7.

.'i.S.
10.

•II,
II'.
i.i.
II.
1."..
III.

17.
4S.
4!).

:a).

5;{.

r)4.
r)(;.

57.

r):>.
<;o.
(ii.

r.4.

Ho.

67.

()!>.
70.
71.
72.

7;{.

74.
75.

76.'

<'\ Milirlla L'iistioido, l\tz.

<' ••ll>|ii,l;itii, AVs.
('. fliiciilpciL'ii, Klz.
<'. l.'uiccdIuiH, I'^Jir.
(". <l('li('t!i., ./. ,SV//.
C. cisliilu. III iiijti I .

«'. llCl«T,,|,|,yll!l, /,V,//.V.

<V Mlliiidii, />y(//.

Niiv iciilii cr.'issiiicrvir, Unit.

N. -riicilis, /;///•.

N. CllSllidul;!, A72.

N. iiiiihiiiiiii, I'Uir.

M. ii|i|(ciidiciilulii, AVa;.

N. iillinis luir. iuii|)|iirliyii(:u.-, I'^iir.

N. Iiaiisvrrsu, .1. ,S'r//.

N. ;iiii|»liii;oin|>liiis, /•;//;•.

r,n- '

N. liiiKtsji, A72.
N. lirtiiji, (nun.

" " rar. liil(s)clifuc.l<ii, /.;///•.
N. Icirmiicii, FJn:
N. ilicct.l.:il;i, Ktz.
N. flliplji;:), Klz.
N. nididsa, Klz.
N'. sciiU'lliiin, O'Meata.
I*inmiliiri;i ohlcjii^a, Rah.
I*. \ iridis, /(\/,/>.

'* " r((r. liemipU'ia, AV6.

I*. |»rri'j;i'iiia,, Klir.

P. iiohilJH, a;///'.

P. inajoi', li<tl).

P. dactyl us, AVs.

I', ^iliba. A'A/'.

I^. divcrirciis, W. Sm .

P. iiitt'rni|)ta, IF. Stn.

P- iiK'solopta, A7A/'.

P. iiudo.sa, Kkr.

Staiirorieis plKciiiciMitoroM, Kkr.

St. gracilis, W. Sm.

St. ance|)8, f]/n:

St. t'lilinen, 7^re/>.

St. punctata, Kfz.

St. stauropheria, Elir.

Surirella robusta, Uhr.

[S. spleudida, E/ir.

Onjdiiir SilitrAius Rrvuiins. 241

77. S. liiHi'iiiilu, lin;h.

7H. S, hitroiiH, K/z.

1'.). S. tiifiziilii. U'. Sill.

so. S. Imcaris ror. ctniHtrii.tu. W. Sm.

s|. S. slcvKM-iisiiJ, (,'nin.

i^'l. S. i'l«"j-iinH, f'!/ir.

H'.i. S icii.'ia. <in<f.

XL S. ranliiiulis, Kiltoii-

Hh. Nil/scliiii ain|)lin>xv.<, FjIii',

S(>. N. I'luiiLriilii, ilnin.

87. N. spt'ctjiliilis, Hull's (?)

SS. N. ^iiiiiioiilfiu Silzxrli.

HK, St('Iln|tt(I-ulii!l illlC.t'ps, Hill}.

DO. Ffii;_'illiiri!i <'oiiN(nH'iis, dnm..

j)I. '« " *"?>•. ItinutJiH, Oriin.

1)2. I"'. ( apiKiiia, l)isiii.

:>:{. !•' lata, ir. Ny//.

tH. SviH'dra nliia, M/ir.
'.).'"). Mcriiliiiii ♦•ircMilai'i', .(//.
l>t). 'I'uliellaria tlDc.iilosa, Hoik.
'.)7. T. fViu'Htrata, Li/nj/h.
98. Cyclutclla oppniulaU, J//.
9I>. C. coiutii I'll)-, alfiiiis, <7/v/H.
ion. Melosiiii.li.'^taiiP, Khr.

101. M. arcnaria, Moor.

102. M. (iriclialci'a, Martenn.
W^. M. <,'ramilata, ^vV/r.

104. M. crt imlata i^ir. vuliila, Uniii.

This lint is not oxhaustivc. of all the forms found in any <;iv('n
locality, much Irssof all the sptjcies iu the lacustrine denosit.s of
the jtrovinee. Until (he siuicies havy been more fully determined
in the whole; range of deposits there will bo little u.^c in attompt-
inji; tin compare the forms of the lower deposits with those of the
upper or more modern. Great variations are observed in many
Mpecies of the diatomace.t), concomitant with their stage of develop-
ment, and also probably with their different eavi'-onments. The
conditions oi' I'nvironment also affect their distribution. It is
ren'.arkabie in the Nova Scoti an species, so far as observed, that
v/hile most of the forms di'tcrmined are also found in the dis-
tant waters of the Alps and the Jura, some of the depositis taken
from lakes but a few mikis apart can be distinguished by the pre-
sence or abseuee of certain lorms or by their relative abundance.

Oi'U

ItlhW,

S'l

n rniis

n

r)iiii.i us.

This iiiiliict inn \^ n-^ yet ha-^nl on Ikh I'tu i nuTiilur i»t nltscrv-

atioiiH to In! oCimv sciciitifir viiliK

Hut

KiU'h Mistiiin'CiJ as

rnl|((wiil'_' llilV(3 been obNTVi*! : Mthmhti nnnniid

( Mdor

till'

:iltuiHl:mt in till) Kiirltowti liiikos iitvir tJif snnmritof'ilic ('HlHcpiiij
raii!^!' (if iiii>ii»'t:iiiis , wliilr <Jiillry Ijiiko. a I'rw lllil('^ on the otlitT
sidr oI'iIh' \vat(!rsli('(l, is (list"m;:nislu'(l liy the pri'siiici (\\' Sh nnp-
Irrnhii niici i)s (Jjrwis) Mivl). , and Ma<'l\iiitosli Ijakc. S('|Kirali'tl
only l)y a Ccw miles oC uionnt.ain ri(lt;c ami toroht, from liotli, con
ta ins, a|i|»a rent ly noitlicr lliis spccirsof JA /'(.s//v( nor Slmniih rithiu ■
ami tilt" deposits of Loeliaber lake aro characteri/.eil by t.lie rela-
tive abundance o\' (^i/flii(i//i. Of course tbese laki' de|»osit>* eon-

liicli li

but

tain, not only trie or<;anismM wtiieii live in tJieir own waters, tii
tliose wbieli are swept'into lliem by tlieir tributary streams.

In addition to tlie I'l'iiiains of the diatomace.'v, tbe silieeou5
spicules ofsponi^es abound in all tbese (leposits, especially llie loiin
skeletal s|)icules. In some few places, tbe silica from this source
is in excess oftbat from tbe diatomace.'i'. A seandi for tbe orii^iii
of tboBC bavini^ been ma<U' last suiiiukm' no less tbaii niiir speclt-s
in /our j:;(>nera liavc boon Tjund, and two of tbese are con-
si(U>r(!d as new to science. Tbese fresli-watir spon<j:es i^row on
submeri;'e(l wood, ]>lauts, stomas and oav.u on sand, Tbey are. all of
some luie of i^retMi wben livinu; and exposed tot.be influeiute of
li^bt. 'I'bcy vary in size from very small up to a speeiiiKMi of
.\I(i/ini(i jfiivhifilis, :.',rovvlnu; in (Janbni-of-Kiden Lake, wliieb mea-
sured twi>iity-seven iiiebes ir; li'nijtb by lour iiudies in diameter.
Hurroundinn a small brancli as a core. In tlu; winter st>ason tbe
flo.sb of tbese generally decays, and most of tbe skeletal
spicules scatter and aci^umulate in tbe adjacent deposits. Tbe
reproductive gemmules vvitli tbeir cbaracteristic spicules, also, in
the course of time float away, or germinate next spring on the
orie;inal site. The fbllowini;- are the species oi' siliceous sponges
which have been identified as living in the lakes at present, and
whose spicules abound in tin; (b'posits under consideration. These
sponges, like the diatoms, have certain spiicies characteristic of
certain waters, while others are more generally distributed.

1. Sjwngilla fragilis, Leidy.

2. S. lacufitris var. dawsoni, Hk.

3. S. mackayi, Carter.

4. Meyenia fluviatilis, Carter.

'•I nliscrv-
'••'.^ .IS fll,'

(.M<M)rj is
''"lH(|iiiij

III"' n(||,.,-
'1 >S/( nnn.
••^''IIItl-ilM'd
'I'tll, ('(111
fill inhin ■
flic n-lii-

Ills.

■^iliccdu."!

(Ilf luiii^

is source
i»> (iri^iii
'' species
iro ('ori-
i^row oil
in; Jill of
i('ii(!e ,,/'

illKMI of

I'll uiea-
ameUir,
sojj the
skeletal
. The
Jso, in
oil the

JXIIl^OS

t, and
Those
■itic of

.'». M. even 111, /'«//.sun«l )fills.
t(. lleieioineyeiiiii ryileri, I'oHh.
7. n. iir;^\ ru,-j|K'riii!i, /'»<//.v.

S. II, |>i*:l(>Ve||MIH, /'(f(//.s',

"J. 'riiliellii |»eriiiMylviviiifu, I'litts,

'I'hi! first ol'tlieso was deserilieil by |{ovv(irl»!iiik as S.lon/ii. The
s|>(ciii)eii ciiiih' IVoiii Uritisii ('oUuiihiii. It was first dise(»vt;n'd
ill Kii;^hiiid last suiiiiiier, .iccordiiii;' to (artcr. It turned out on
exaiiiiiiatioii, that lA^idy, ol' IMiiladi-iphia, first di'scrilted it as .S'.
JriKjilis. Mo. 'J wasdeM'.riluid by HoworbaiiU over twiiiity years aj^o
as »S'. (/iiir.soiii ; iiext, by IVitts as »S'. btcualroidts. I (rallttd
Mr. Potts' attention to Uowerbaiik's dos(;ri[)tion, and it lias boeii
j:;cntwally eoneeded ^inee to be an Anieri(Mii variety (d' the Kuro-
jteaii S. liu:iiHtria. No. 3 was described by (barter, of Kiit:,land, in
the January niuiiber of tlie ''Annals and iMat;a/.ine of iNatural
History,' London. I'otts chiinis that it is the same as his »S.
iij/noi/urmisy a description of which, we think, has not yet bi^eri
published. No. r> is reuiarkabh!, as the species has never been
observed before except in a p(»nd upon Mt. Kverett in Mass.,
U.S.A., at an elevation of 1,800 or 2,000 feet alxjve the sea. It
apjiears to be pi' ntiful in Nova iSeotia. No. S, provisionally named,
is remarkable for the paucity of its .'• .,atoblasts, wiiich for some
tiuio prevented its cla.-sitieation, although its skeletal spicules are
very distinctive. Further investigation is neeessa.y for the elucichi-
tion of the character and life-history of this spe(^i(!s. This
classilieation and nonieiiclature has the a[»{)H»val oi' II. .1. (barter,
th(! i-reatest living l<]iiglish writer on sponges.

K. I'otts of lMiil.i<lel[>liia, our l»est American authority, has
observed that the s|»icules of spongi's undergo variations within a
very considerabk; limit, and that, these variation.s arc; geniu'aliy
concomitant with the variation of the altitude of their habitat.
The spicules of several of thcH; Nova S(u)tian s{»oiiges he con-
siders as varying Irom the usual type, but considers them a.-, con-
forming to his hypothesis. The extensive deposits of these
siliceous remains must have eoiue proximately from silica in
solution in llu; water. The analysis of the waters of lljilifax
lakes by Prof. Lavvson sliows the preseiict; t»f soluble silica as well
as of alumina, lime and Iron, all ol' which have Iteeii found to
exiht in diatomacuous earth.-? analy.scd by Zeigler, Iloliiuau, aud

1

244

Organic Siliceous licrtmUis.

LoHMier. N„ less than from 2.13 .ntii.s io 2.44 per ^^aWuu of
t.iese inor-anK! Hub.stunees were fbuiul in .solution in the waters
of theHc lakes. ''^

Hum paper wan writtoiMM annwcT t... a n.pK-st for tl.e Author'n
oh.s(Tvat.io„H on tlw .Jiafon,ae,.ous .l.-posits of Nova Scotia. It was
Mnnpy^Mvcnasan.pnrtof the pn.j,r,es,s ,.(• tlu- Autl.or'H own