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INDIANA UNIVERSITY BIOLOGICAL STA
Hydrographic Map of
TURKEY LAKE,
OR LAKE WAWASEE, KOSCIUSKO CO.,INDIAI
BY
CHANCEY JUDAY,
From
The Government Surveys and Surveys ar
soundings ,made during the summer of 1895
CHANCEY JuDAy, D.C.RIDGLEY and THOMAS LAF
Contributions From the Zoological Laboratory of the Indiana Un
under the direction of CARL H.EIGENMANN,No.15c.
48 42 3V( 62 SEATION UT
ee \
SN
Ht
( |
°
RSQ ooo 1890 ge90/t
220 mato2 £90 7.
Scale 1:10560.
Vertical Scale
for
CROSS SECTIONS:
i
s1524
Scale of Depths
ies
a
——-10-60, BoTTOM ConTOoURS
_—~___- 10 Ft ELEVATION LINE
MARSH
UR ay Lat
Sun CAT TAIL SWAMP
% SPRING
=== ROAD
3-69,FEET IN DEPTII
INDIANA UNIVERSITY BIOLOGIGAL STATION.
Hydrographic Map of
TURKEY LAKE,
OR LAKE WAWASEE, KOSCIUSKO CO.,INDIANA.
BY
CHANCEY JUDAY, '
From
The Government Surveys and surveys and
soundings ,made during the summer of 1895, by
CHANCEY Jubay, D.CRIDGLEY and THOMAS LARGE.
Contributians From the Zoblogical Laboratory of the Indiana University.
under the direction of CARL H.EIGENMANN, No. 15¢
P_sap_ ope __isgeapgo/?.
20 to Op0 Tm
Seale 1:10560.
Vertical Scale
for
CROSS SECTIONS:
s
ped .U-BIQLOGICAL STATION
T
4 . * = ——
Di _\/ VAwrer PARn j
\o
1sIsze
Scale of Depths:
i L,
—— 10-60, BoTTON CONTOURS
10F¥ ELEVATION LINE i
203
FIRST REPORT OF THE BIOLOGICAL STATION.
ConTEnts.—Drrecrors’ First Report or BioLoGicaL STATION.
Introductory.
Acknowledgments.
Equipment.
Plankton ret.
Sounding apparatus.
Additional equipment.
Plan of work.
Part I.—Turkey Lake as a Unit or ENVIRONMENT.
Introductory.
Orientation.
General features.
Size.
Relation of water to outflow and evaporation.
Constancy of Turkey Lake as a unit of environment.
A Preliminary Report on the Physical Features of Turkey Lake—D. C.
Ridgley.
Hydrographic map of Turkey Lake—C. Juday.
Temperature of Turkey Lake—J. P. Dolan.
Part IJ.—Tue Inwapirants or TuRKEY I.AKE.
Note on Plankton—C. H. Eigenmann.
General Fauna—C. H. Eigenmann.
Leeches—Mrs. B. C. Ridgley.
Rotifera—D. 8. Kellicott.
Cladocera—E. A. Birge.
Decapoda—W. P. Hay.
Mollusca —R. E. Call.
Fishes—C. H. Eigenmann.
Batrachia—C. Atkinson.
Snakes—G. Reddick.
Turtles—C. H. Eigenmann.
Water Birds—F. M. Chamberlain. =
Part IIJ.—VaRiATION.
The study of Variation—C. H. Eigenmann.
Variation of Etheostoma caprodes—W. J. Moenkhaus.
204
TURKEY LAKE* AS A UNIT OF ENVIRONMENT, AND THE
VARIATION OF ITS INHABITANTS.
First Report or THE InpranA University BroLocican Station. By C. H.
EIGENMANN.T
IntropucrorY.—At the last meeting of the Academy I outlined a plan for
the future work of the zodlogical section of the biological survey of Indiana. It
was, in brief, to study some lake as a unit of environment and the variation of its
inhabitants. This plan has materialized, and I present this as the Biological Sta-
tion’s first report.
To select a suitable site I visited, in February, 1895, lakes Maxinkuckee, Eagle
and Turkey. The lakes were frozen over, and I had a good long walk over Max-
inkuckee and a sleigh ride over Turkey Lake. Turkey Lake seemed well suited
for a starting point for the work in hand. In March I again visited this lake to
look for a suitable laboratory and quarters. A laboratory was found in a large
boat-house belonging to Mr. T. J. Vawter, the owner of Vawter Park. The boat-
house is directly on the water’s edge, in about 86° 18” east longitude and 41° 23.57
north latitude. In March the lake was still frozen over with but a narrow rim of
free water near the shore. When I again visited the lake, to make the final ar-
rangements, on the 30th of May, and captured snakes, turtles, frogs, and two spe-
cies of spawning fishes, all within a hundred feet of the laboratory door, I was
convinced that no mistake had been made in the selection of a locality. Deep
water near the laboratory, a spring at the laboratory door, the situation of the
laboratory nearly eyuidistant from either end of the lake, high land all about the
laboratory, the nearness of such large bodies of water as Lake Tippecanoe of an-
other river system, and a large number of smaller lakelets within a mile of Turkey
Lake, all contributed to make the location selected as near perfect as could be ex-
pected.
“The only recorded name of this lake seems to be Turkey. It appears so in the govern-
ment surveys of 1838, and on all the maps published since that time. I am told that it re-
ceived that name from the fancied resemblance of the general outline of the lake to a
Thanksgiving turkey. During the last few years the lake has been known to those person-
ally acquainted with it as Lake Wawasee, and there seems to be a laudable ambition that
this latter name should supplant the homlier, but more significant, name of Turkey. The
lower lake is locally known as Syracuse Lake.
The following letter was received from the Director of the Bureau of American
Ethnology: In response to your letter of December 6th last, I beg leave to inform you that
the word ‘ wa-wa-see,’’ “ wa-w4-si’’ or ‘‘ wa-w4-sing,”’ signifies ‘‘ at the bend of a river.”’
Yours with respect, J.W. PowELL.
{Contributions from the Zotlogical Laboratory of the Indiana University, No. 14.
205
A twelve-room cottage was rented, in which fifteen of the members of the Station
besides my family were quartered. While « summer cottage, thus peopled, is
not a good place for consecutive thinking, this experience will also be remem-
bered with pleasure. Most of the students rented a large dining tent and hired a
cook. Others tented and boarded themselves. Their expenses ranged from $1.25
to $3 per week.
The laboratory was open from June 25 to September 1.
ACKNOWLEDGMENTS.—Mr. T. J. Vawter, besides placing the boat house at
our disposal, gave us camping ground just back of the laboratory, and assisted us
in various ways, both in fitting up the Station and during the entire summer.
I am under many obligations to the officers of the Baltimore & Ohio, the
Vandalia and the Michigan Division of the Big Four for transportation over their
lines leading to Vawter Park, and for other favors.
During our stay at Tippecanoe Mr. W. S. Standish assisted us very materially.
He took the whole party on a tour of general inspection about the lake from end
to end, and placed himself and his steamer at our disposal during our entire stay.
~The Pottawatomie Club granted us the use of their reception room, where
some of the lectures were delivered.
Professors Birge, Kellicott and Call have prepared accounts of material col-
lected during the summer.
I must especially thank Dr. J. C. Arthur, Dr. G. Baur and Geologist Willis
Blatchley, who visited the Station to deliver lectures before the members.
Lastly, 1 am indebted to Mr. J. P. Dolan, superintendent of the Syracuse
schools. He first directly, and through Mr. Eli Lilly, of Indianapolis, called my
attention to Turkey Lake, met me at Warsaw, and guided me to the lake and over
and around it on my first visit. During the summer he furnished the Station
with a splendid row-boat, and by his knowledge of the lake and its surroundings
and personal acquaintance with the natives contributed much to the success of the
undertaking.
EquieMENT.—The equipment of the Station consisted of a room 18x30 feet,
with six windows on aside. In this space the twenty-two members of the Station
were provided with tables. Continuous with this available laboratory space was a
space 18x20, opening by very wide doors to the lake front. This space was util-
ized for storing apparatus. The apparatus, nearly all furnished by the Indiana
University, was as follows: Compound microscopes (Zeiss), 21; dissecting micro-
scopes, 3; microtome, 1; dredge, 1; plankton net, 1; Birge net, 1; dipnets; re-
agents, about 200 bottles; working library, about 200 volumes; Wilder’s protected
thermometer, 1; lamps, glassware, etc., the usual equipment of a laboratory
206
table; two boats; one sounding machine. The plankton net and sounding appa-
ratus and the method of using them may be described here.
PuangKton Net.—An idea of our plankton apparatus and its modus operandi
can be gathered from one of the illustrations. The sounding boat was fitted in
the stern with a swinging derrick. Through the end of this was attached a
pulley, through which the rope supporting the net passed. The derrick was high
enough to allow the net to swing clear of the sides of the boat, so that when a
haul had been made, the net could be swung forward over a tray of tubes, ready
to receive the condensed plankton. The depth through which hauls were made
could be ascertained either by means of the sounding apparatus or by the direct
measurement of the plankton rope. The plankton net was built essentially as
devised by Hensen and Apstein, except that the straining net of No. 20 silk bolt-
ing cloth, Dufour’s, was permanently attached to the truncated cone of canvas.
The bucket which receives the plankton was from necessity greatly simplified, but
as no measurements were made with it, and further improvement, both in effi-
ciency and simplicity, have heen devised, I will describe this instrument as it will
be made for next summer
The diameter of the bucket will be made one and one-half inches. Its bot-
tom will be of a sheet of brass or copper, hammered so that it will be slightly
concave or cup-shaped. ) AQ). B90 seated cerees 39 | * " BBE essceai| Fes 35
“Surface near
Shore: wesun| eso! 46) |) $385) BL seccss| occa cote 365] AGE|- scces|lnscex<] ares
Precipitation cssesal! seal nssesel! devel seveseleeveca|| vave'| wasdeal-seaey, || abe ell eeeseel| zoeveal| weszes| wants
j
December... 1 | 3 4 | 6 | iG 8 | 9 | 10} 11 |
Air {7:30 a.m nae (sia eee 12 | 36 | 28] 24 | 28] 32
5:00 P
Surface
Bottom . ‘
Near shore ...] .....| 34 | -.2-| ee. 2] Be | BSH ccuve'el|| seein wbeis
Precipitation] 56 | ......) 07 | 2.0] oe Rea len veal Sli
December ..... 19} 20} 21
«(7:30 a.m.| 52 | 52] 40
he Eee 54} 52) 39
Surface .. 334) 354) 37
Bottom. <4. 373| 37
Near shore ...| ......] 43 | .....
Precipitation|1.87 | .96 | .12
* Broken thermometer. + Under ice. t Common thermometer.
SUMMARY OF TEMPERATURES.
SEPTEMBER. OcToBER. NoveMBER. DECEMBER.
Date. | Deg. | Date. | Deg. | Date.| Deg. Date. Deg.
4
3 ALD ecssccdedcensss 22 86 3 68 61 19 54
a Surface, 25 ft| 22 73 3 63 18 43% 21 387
2 | Bottom......... 22 69 8 56% 26 45 20 37%
=
2
S| i ascerpunis 24 7 19 26 27 6 |{ ae 7
z | Surface, 25-ft} 30 56 31 39 30 34 » 7,8, 9,10 33
s Bottom, 25 ft} 30 57 31 39 26 36 6; 8, 9, 15, 17, 18, 19 35
g
& | Air... 47.8 36.7 317
a | Surfa 51.7 41.2 3312
# | Bottom .. 51.57 41.93 3538
<
N.B.—Water general average for three months higher than air.
70
238
AIR. Surracs. | Borrom.
Grand average for four MONEHS.......secereeseesessecsccesseeteeeeeees 42.94 48.37 48.87
From December 3 to noon of the 20th the lake was covered with ice. During
this period the surface temperature varied from 33° to 343° and the bottom from
35° to 36°.
At 5:00 p. m. of the 20th, ten hours after the ice started to move in a body
from the lake, the surface showed 353°, u gain of 23°; the bottom 374°, another
gain of 24°, and in the shallow water, fifty feet from south shore, where it had
been 32°, 33°, 33° on the 7, 8 and Yth respectively, it was now 43°, a gain of 10°,
The next day surface and bottom both registered 37° degrees at the twenty-
five-foot station.
The results of these observations are embodied in the accompanying profile
chart, in which it has been attempted to show the absolute and relative move-
ments of the air, surface, and bottom of lake at a depth of twenty-five feet.
al
~
”
joe eet.
— are
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a
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A
. ees ees oe
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;
due -4----4
t
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i
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Aittrhler Oteter Wotidend.|
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-t---t—
erp ct
g
g
2330 § ©10~«SWSs“‘i2SCG ODO Pe eOy c ee GS
Temperatures from September 23 to December 23. Broken line, temperature of air;
dotted line, temperature of water 25 feet below surface on the bottom; continuous line, tem-
perature of water at the surface at the same place.
239
(a) A few well-known facts are emphasized, the variableness of the atmos-
phere and the persistence of the water; that water is a poor (d) radiator and an
indifferent conductor of heat, and responds slowly to atmospheric changes.
(d) It shows also that the great volume of Syracuse lake at no time has been
stagnant, but that a condition of activity has obtained throughout the'entire period
of observation.
(c) For the four months in which a large number of observations were made
the general average of the water, both surface and bottom, is higher than that of
the air.
A difference of 10° between the water one foot deep near the shore and the
surface mid-lake during a rain the day the ice left the lake, shows that the surface
drainage is no small factor in winter and spring in raising the temperature of
the whole body.
PART IT. THE INHABITANTS OF TURKEY LAKE.*
PLANKTON.
By plankton, Hensen, the author of the word, means everything floating in
the sea and passively driven about by the waves and currents. Haeckel in-
cludes under plankton all organisms swimming in the sea. Haeckel says:
“The totality of the swimming and floating population of the fresh water
may be called limnoplankton.” Limnoplanktonic studies have been made when-
ever a collector scooped for protozoa, diatoms or other minute organisms.
Planktonic studies of this sort have been carried on for along time. Recently
plankton has been studied in a new way, first in the ocean and more recently in
fresh water. This more recent study has been the quantitative and qualitative
estimation of the plankton if a given volume of water. There seem to have
developed in a remarkably short time two schools of planktonists, the one headed
by Hensen asserting that planktonic organisms are uniformly distributed, the
other, headed by Haeckel, being equally sure that planktonic creatures are to be
found in clouds or schools. We are interested in plankton only in so far as it is
part of the environment of the vertebrates inhabiting the lake. That it is not an
unimportant element of the environment is due to the fact that it forms the
primitive food of most of the fishes and that at the most plastic period in the life
of the individual. The amount of plankton, as well as its composition from year
*Contributions from the Zodlogical Laboratory of the [Indiana University, No. 16.
240
to year, is therefore of prime importance im the search for the causes of the
wee in the same fish in two contiguous lakes or in two successive years in
the same lake.
Our plankton apparatus was completed too late to enable us to make any
systematic measurements, especially as our planktonist was actively engaged in
the physical survey of the lake. But plankton was collected and some of its
different constituent: will be reported apon.
A good historical account of planktonic studies, as well as exact definitions,
are to be found in the Planktonic Studies of Haeckel, translated by G. W. Field,
and published in Commissioners’ Report. 1889-91. U. S. Com. Fish and Fisheries,
pp. 365-641.
In the following sketch several groups of animals are not at all considereds
and others but briefly. The only groups found in the lakeof which we approxi-
mate a complete list are the fishes, batrachians and reptiles. Deficiencies will be
removed in subsequent reports when a classification of the material into littoral,
bathybial and pelagic will also be attempted.
> PROTOZOA.
The P-fozea were not represented by a large array of species during the summer.
No detailed work has been done on them as vet, but I want to mention two
characteristic forms.
The most striking Protecoan is Ophridium. It is found in clumps varying from
microscopic minuteness to the size of walnuts, and in different parts of the lake
the pebbles and exposed parts of clam shells are covered with these colonies to
such an extent as to suggest young lettuce beds.
Ceratium hirudinella is as striking and abundant in the pelagic regions as
Ophridium is in the littoral.
In this connection two plants may also be nbtio:
Rirularia is very abundant during the whole summer. It is conspicuous in
- calm weather, when it rises to the surface. Toward the end of August and in~
early September it collects in such numbers as to form large patches and streaks,
forming a true Wasszerbliithe.
Various forms of Palmelia are abundant during the whole summer, and in
October, when Rirularia has disappeared, it forms large patches on the surface
forming the Wasserbliithe oi the late fall.
PORIFERA.
Sponges are not abundani in the lake. They are found im small patches on
boards, sticks and other things near the margins of the Jake. They grow much
more luxuriantly in the outlet of the lake where they sometimes form patches
several square feet in extent.
CNIDAREA.
Hedra viridis L. Specimens of kudra were exceedingly rare. On one occasion
a few were taken on a submerged stick near Black Stwmp Point.
PLATHELMISTHES.
Fist worms were noi systematically collected and none of these collections
have been identified. OF Turéellarvan: there were several species. Amie calra is
infested by a tape worm and by a Disteman.
NEMAYTHED MIA.
No atiempt was made to collect thread worms Govdiu: is exceedingly
abandant on the margins during the latier part of summer. I counted as many
as twelve im the area of one foot square. S
ANSELIDS. BY BESSIE C. RIDGLY.
No Cheviopada were collected.
Ne systematic attempi was made to get large numbers of leeches, but speci-
mens were preserved whenever found. Im the classification I have followed
Vemill.
Nepielis fervida Verrill. Fourteen specimens.
Clepsine parasitica Diesing. Three specimens.
Clepsine wrnata secata Vermll. This species was noi found m Turkey Lake.
Two specimens were taken iu Tippecanoe Lake.
Clepsine ornata ragexe Vermill Four specimens.
Ciepsine senata variety d VerriilL Ten large specimens corresponding with
the second specimen described by Vertill were found, most of them on turtles.
Clepsine papillijere Verrill. One specimen.
Clepsine papillifera covinaia Verrill. Three specimens. One oi these, one-
half inch long, was found under a stone im front of the laboratory. A number of
Young were attached to it.
Clegsine paltida Verrill. One specimen.
Clepsine paliida variers b Verrill. One specimen.
Clegsine degen; Verrill. Five :pecimens.
242
Rorirera. D. 8. KEvuicort.
I received in September three vials of plankton, from Mr. Chancey Juday
with the request to report upon the Rotifera found therein. The vials were
marked and described as follows: ‘‘I. Contains plankton caught at the surface
of the water of Wawasee Lake, Indiana, by using a plankton net; taken August
28, 1895; killed in picro-sulphurie acid; washed in 35 per cent. and 50 per cent.
aleohol and preserved in 85 per cent. alcohol.” ‘II. Depth of haul, 60 feet
(Wawasee) ; depth of water, 65 feet; taken July 20, 1895; killed in Flemming’s
Fluid; washed in 85 per cent. and 50 per cent. alcohol, and preserved in 85 per
cent. aleohol.” ‘‘III. From Tippecanoe Lake; depth of haul, 110 feet; depth
of water, 117 feet; taken August 7, 1895; killed in Flemmings’s Fluid; washed
in 35 per cent. and 50 per cent. alcohol, and preserved in 85 per cent. alcohol.”
I find that the Rotiferu were much better preserved in II and III than in the
first. The illoricate species in I were scarcely recognizable ; in fact three species
found in this vial I have not been able to place more nearly than the probable
genus. Those in II and III have all heen satisfactorily identified. While the
whole number recognized in these collections is not large some interesting facts
are brought to light. Three species not hitherto reported from this country are
among the number, and others rarely. It is certain that the rotiferal fauna of
these lakes is rich and will yield many unique forms as a reward to any student
who may be able to work in the region, to take and study them in the fresh state,
and in all their varied relations and situations of residence.
I shall enumerate, with remarks, the species found in each haul separately,
although it will cause some repetition, and in the order of Hudson and Gosse’s
Rotifera, without citing the bibliography farther than a description where the par-
tial bibliography, however, will usually be found.
I.
1. Floseularia mutabilis Bolton. Not infrequent. It is quite unexpected
that a floscule should occur among pelagic species, and yet there are four known
species of these Rhizota that cut loose and become sailors. Mr. H. 8. Jennings
has found three of them in St. Clair and lakes of Michigan. Of this one he says:
“Very common in towings from Lake St. Clair, either at the surface or near the
bottom. Hudson and Gosse, I, 56.
2. Cieastes brachiatus Hudson. A large number were found, but it was im-
possible to identify them surely. The tube conforms to the figures and descrip-
tions of that of Brachiatus ; it is cylindrical, smooth, compact, perfectly hyaline,
243
often containing a slight amount of adhering matter, often containing several
eggs, which, however, are not so elongate as the figures represent those of
Brachiatus; the loug narrow foot and the Jong non-retractile antenne agree well
with the type. I am pretty confident that it is Brachiatus, yet I am surprised to
find so many of them, or any of them, in a surface tow, as it is evidently norm-
ally anchored ; perhaps they were attached to floating algw which apparently are
not uncommon in the lake. H. and G., I, 83.
3. Philodina megalotrocha Ehrenberg. Numerous. I have often taken it
at a distance from land, particularly in shallow lakes or among floating alge.
H. &G., I, 101.
More than one species of Motifer which could not by any means be identified
were present.
4. Sacculus viridis Gosse. Rare. H. and G., I, 124.
5. Polyarthra platyptera Ebrenberg. Many seen. The serrations on the
edges of the broad plates are coarse and more distant than in the type. H. and
G., II, 3.
6. Dinocharis pocillum Ehrenberg. One individual. It is a bottom feeding
species and rarely occurs in a surface tow. H. andG., II, 71.
7. Dinocharis collinsii Gosse. One. Bottom feeding species. It has not
been observed in this country before. No species exceeds it in beauty. I could
not make out the pair of spines on the foot and the edge of the lorica appears to
be set with a row of small spines, rather than being serrate as described and
figured. H. and G., II, 72,
8. Anurea cochlearis Gosse. Exceedingly abundant. Our form differs
slightly from Gosse’s figure since the mesal ridge of the lorica does not extend
straight from end to end, but has a decided angle at each pair of facets, the an-
terior median one is not divided. H. andG., II, 124.
9. Notholca longispina Kellicott. Not rare. This rotiferon was first known
in the water supplies of cities along the Great Lakes. Soon after it was described
jn 1879, it was found in Olton Reservoir, Eng., and then by Imhof in the Swiss
Lakes. More recently it has been found in lakes of America. Mr. Levic reports
finding the eye spot double, or so far separated as to be regarded as two eyes. I
have seen several in these collections with the same peculiarity.
244
II.
1. Polyarthra platyptera Ehrenberg. Few.
2. Triarthra longiseta Ehrenberg. Comparatively few in this vial. H. and
G., I, 6.
3. Ploesoma lenticulare Herrick. Very many. It occurs in the lakes of
Europe. In this country it has been reported only from Lake St. Clair, both in
bottom and surface tows (Jennings). Zodl. Anz., Bd. 10, 577.
4. Brachionus militarw Ehrenberg. Rare. I have found this an abundant
species in ponds of western New York; it is a good sailor, preferring small seas,
however. Authors have recorded the fact that the posterior spines are not in the
same horizontal plane. This seems to be in relation to the habit of always turn-
ing on its long axis as it swims; they appear to bore their way through the water
H. and G., Sup. 82.
5. Anureea cochlearis Gosse. Many, but far less numerous than in I.
6. Notholca longispina Kellicott. More abundant than in I.
U1.
1. Asplanchna priodonta Gosse. Quite numerous. Jennings reports this fine
species as abundant in Lake St. Clair, both at the surface and in deep water. H.
and G., I, 123.
2. Polyarthra platyptera Ehrenberg. Several found.
3. Triarthra longiseta Ehrenberg. Numerous.
4. Diaschisa valga Gosse. Only one seen. It appears to agree well with the
figure and description. H. and G., II, 77.
5. Andra cochiearis Gosse. Not common.
6. Nothoica longispcia Kellicott.
CLADOCERA. | seo deeded sana yoeee
Hartford Key... cues sriese Gay Saareeades 4 10} 3 Le eee
Green River, Greensburg, Ky............... 3 108 1 De sexe ae &
Little Barren River, Osceola, Ky............ 4 a hand (eeeeearar gs a eee
Little South Fork Cumberland River, Wayne
County;: Ky veane eek sawn wees se sh oot ans 1 DD.) lbesavesece A Neetu
Eagle Creek, Olympus, Tenn............-.-. 2 i Ca ears De pacts cle
Obeys River, Elizabethtown, Tenn .......... 13 11,5) 1 5 7
Watauga River, Elizabethtown, Tenn........ 2 103 1 Sf) Hh tach dail
North Fork Holston River, Saltville, Va..... 1 DS esceien det:| cna a!
Eureka Springs, Ark.............00020 sees bE eerie earn peereta Parra:
Chocola Creek, Oxford, Ala ............-... 4 TUE | ae eiies 3 1
San Marcos Springs, Tex ...........-..02055 2 iI Peace QU Sl ntvauusbie
280
TABLE B.
A wn wm n D wn
hn
5] Bg ($2 SE /SE[S (8%
: S| ge |ptiat| aA) a5| oe
LOCALITY. B| 57S, JA 2 e|P gf a |A a
SUT] ion | oe es Pe Blom [Ss
ro oS u ls = w a nm = ue a
D> nk |o alo wnlounl/o alow
EC bine
A) $8 (sso a/2 8[8 8/8 &
Zz < 4 14 |A 1A I4
Toreh: ake; Mich: ..0.292s.sc0easr ee eees Be 7) 149 3] 4
Cedar Rapids, Iowa ............... 000.005: 1} 14 1
White River, at Indianapolis .............. 1 14 DL) lhscsexs
Gosport; Inds....5 vest woe daa age Beets 5 | 144 ]....) 1] 4
Bean Blossom) Indie ees cesses cede se 17) 148) 1]| 9] 7
Rushville, Und. cccue yrs vee neeke ee cae os eanese I 14 are eee Oa oer
Wild Cat Creek, Ind ................0..04. ] 15 1
Pike Creeks LG: sels eg case die doh aka 2) 143 1} 1
SW O1Si cies Fae tsadien ate heaps 1 WO 7] itelhaegeucth)
Nipingile Wake;, UWhn.avccorney Qctecceraawes| 2b) TAP pact Ab) 1
Monongahela River ........... 2.000000 Ds Be: (Waceseedaareace| Ly ena.
Harttords Wyss cops scoas ee cena sy ores sets Be RB Wietce ti Dep S24 ilk
Green River, Greensburg, Ky .............. 8) AS. |esselecee| BF lawes
Little Barren River, Osceola, Ky........... AN LO Wega de) Zo" ah
Little South Fork Cumberland River, Wayne
County. Key. wuitdckes dices Sees oar ganas 1) 16 Doe canson
Eagle Creek, Olympus, Tenn .............. De! AOA Neacctelanien asec || 1
Obeys River, Elizabethtown, Tenn.......... 13 TGS eves iiesc] 2) 3 8
Watauga River, Elizabethtown, Tenn ...... 2 153 1 1 ;
North Fork Holsten River, Saltville, Va....) 1 | 16 1
Eureka Springs, Ark .................0.02. TO) GE peasausfoecaeaecel|| Gb
Chocola Creek, Oxford, Ala................ 4. TOS" se| resale S22
San Marcos Springs, Tex .................. 2) -F8e | 1) Di yeees
The color-pattern varies from a probably primitive, simple pattern consisting
of alternate whole and half cross-bars distributed along the entire length of the
body through the pattern consisting of whole, half and quarter bars, having an
incomplete longitudinal series of lateral spots to a pattern having a very promi-
nent longitudinal series of dark lateral blotches with fine reticulations on the back.
Between these different patterns all stages exist, so that they can be connected by
regular steps. Those specimens inhabiting the lakes were found to possess a pecu-
liar color-pattern. This was derived from the primitive, simple pattern by sup-
posing the lower part of the whole bars to have become much broader than the
upper part, and then to have shifted backwards slightly.
281
This lake variety (manitou, Jordan) is one of the most abundant of the fishes
in Turkey and Tippecanoe Lakes, and upon it the results given in the following
pages are based.
Six hundred specimens, all that were collected from Turkey Lake, and three’
hundred of those collected from Tippecanoe Lake, have been examined with a
view, first, of making a comparison of this species in the two lakes, and second,
of determining the range and character of its variation within Turkey Lake itself.
The number of species collected from Tippecanoe Lake is much greater than 300,
but this number was thought sufficient to give fairly good results. The effect of
natural selection will be taken up at a later time.
Etheostoma caprodes has two dorsal fins, the first, a spinous one, well separated
from the second, which is composed of soft rays. The anal fin is composed of two
rather strong spines followed by a number of soft rays. The scales are very reg-
ularly arranged, so that they can be definitely counted along the complete lateral
lines. The number of spines and rays in these fins, and the number of scales in
the lateral line of both sides of the body have been determined. Besides these
characters the presence or absence of scales on the nape has been determined.
These structures have been taken because, with the exception of the last, they
present definite, countable elements, so that in the results the personal factor is
entirely eliminated.
Curves have been constructed to represent the variation in these structures.
In all the curves the horizontal distances represent the countable elements, and
the vertical distances the per cent. of specimens possessing these varying elements.
COMPARISON OF TURKEY LAKE AND TIPPECANOE SPECIMENS.
Conoration.—The coloration of these fishes in the two lakes will be taken up
in detail later. The color-pattern of Turkey Lake specimens is, on the whole, of
amore blotched character than that of Tippecanoe Lake specimens, and shows a
slighter affinity to the simple, primitive coloration characteristic of the Wabash
River forms. The connection of Tippecanoe Lake with the Wabash River may
account for this greater affinity.
SquaMaTIon oF Nape.—In Turkey Lake the nape is as a rule naked, while in
Tippecanoe Lake it is usually scaled. Table I will bring out the difference.
282
TABLE I.
—
€
b §
aus) aes
oh ° os
aos Aen oS
Bae | Ba
Per cent. of specimens having no scales on nape ............. 88.00 19.32
Per cent. of specimens having few scales on nape............. 8.00 23.87
Per cent. of specimens having several scales on nape ......... 4.00 28.32
Per cent. of specimens having nape thinly sealed... .......... 0.20 16.67
Per cent. of specimens having nape closely scaled ............ 0.00 11.74
LATERAL Line.—The specimens of Turkey Lake have on an average two more
scales in the lateral line. The average number for Turkey Lake is 89.46 for the
left side, 89.74 for the right side; for Tippecanoe Lake, 87.69 for the left side,
87.45 for the right side. Fig. 1 represents the curves for the scales of the right
side. The continuous line represents the conditions in Turkey Lake, and the
broken line those of Tippecanoe Lake. It should be noticed that the entire curve
for Turkey Lake is two units to the right of that of Tippecanoe Lake, showing
that practically all the Turkey Lake specimens have a greater number of scales.
Table IL contains the summary of the counts for the scales in the lateral line.
20
I5- he
vay
“ aN
| A_|\
y 4 v
ri L
ia nw {
i mil
i ‘th
i 1 ect
\
5 ; N
7 f 7 oS
LAS eo \
()] aa velo”
80 85 90 95 100
283
TABLE II.
Turkey Laxe. |/Trpr’canor Lake
Left Right Left Right
Side Side. Side Side
Per cent. of specimens having 78 scales.... Ose || ad store aise sew cialieeaacoae
Per cent. of specimens having 79 scales....]........)........|[......00 fe... 0005
Per cent. of specimens having 80 scales.... 0.17 OSB sc conto [ysecceceeie
Per cent. of specimens having 81 scales....|........ 0.34 0:50" |seatecns
Per cent. of specimens having 82 scales.... 0.17 0.34 1.00 2.00
Per cent. of specimens having 83 scales.... 1.37 1.55 2.50 3.50
Per cent. of specimens having 84 scales.... 3.44 1.89 7.00 4.50
Per cent. of specimens haying 85 scales.... 3.78 5.17 8.50 11.50
Per cent. of specimens having 86 scales.... 6.88 9.30 11.50 13.00
Per cent. of specimens having 87 scales....| 11.02 10.68 15.00 16.50
Per cent. of specimens having 88 scales....| 12.56 11.65 15.00 13.50
Per cent. of specimens having 89 scales....| 17.72 14.82 16.00 16.00
Per cent. of specimens having 90 scales....| 12.39 12.98 11.50 10.50
Per cent. of specimens having 91 scales.... 8.08 11.03 7.50 4.00
Per cent. of specimens having 92 scales.... 6.53 5.67 1.50 1.50
Per cent. of specimens having 93 scales.... 5.16 3.62 1.00 2.50
Per cent. of specimens having 94 scales.... 3.61 3.78 0.50 0.50
Per cent. of specimens having 95 scales.... 2.58 38.27 O10. seen cw
Per cent. of specimens having 96 scales.... 1.37 2.41 0.50 0.50
Per cent. of specimens having 97 scales.... 1.03 OsOD ell accecaines [belelatearis
Per cent. of specimens having 98 scales.... AOSV /al bee ee ey | atta ie One
Per cent. of specimens having 99 scales.... 0.34 O34 Weare satin |iecanerecencters
Per cent. of specimens having 100 scales....]...... Ses [ceo ausrane I Peeve ars. a fehawtbaad eas
Per cent. of specimens having 101 scales.... 0.17 (OFS Bra ecprerace eee [eee gree
Per cent. of specimens having 102 scales.... OIL ote Se ee li esieeettraehocnanancat
Per cent. of specimens having 103 scales.... OIL. estietacseestitill iies -oeery [taiaeae dees
ANAL FIn.—The number of spines in the anal fin varies from the normal in
only nine specimens from Turkey Lake and in six from Tippecanoe Lake. This
variation is always toward a lower number, and extends only through one spine.
Turkey Lake specimens have on an average fewer rays in the anal than
Tippecanoe Lake specimens. The averages are 10.87 for the former, 11.15 for the
latter. Fig. 2 represents the curves for the anal rays. Here again, and also in
the succeeding curves for the comparison of the two lakes, the continuous line
represents Turkey Lake and the broken line Tippecanoe Lake. Table III gives
the summary of the anal rays for both lakes.
284
The prevailing number of rays in both lakes is 11; 53 per cent. from Turkey
lake, and 56 per cent. from Tippecanoe Lake having that number. The number
of rays in the next highest per cent. is 10 for Turkey Lake and 12 for Tippe-
canoe Lake, about 27 per cent. in each case.
The range of variation is two greater in Turkey Lake. This may be due to
the greater number of specimens from this lake.
70
sol
cals
50 4 Me
=f FAN
405 ; f
{ } , ‘
30 a :
Er Uc Nak
20 ? +
Fa . 4
tof
fort t ee fet
0 eee 4
7 8 9 10 tf 12 #13
Fic. 2.
TABLE III.
=
2
gus | abs
fbe | £S8
BAH | Bae
Per cent. of specimens having 7 anal rays .................. ONG en itienat
Per cent. of specimens having 8 analrays..... ............ 07K Sal eee
Per cent. of specimens having 9 analrays .................. 1.48 0.77
Per cent. of specimens having 10 anal rays .................. 26.80 15.50
Per cent. of specimens having 11 anal rays .................. 53.43 56.21
Per cent. of specimens having 12 anal rays ................0. 14.13 27.13
Per cent. of specimens having 13 anal rays.................. 0.49 0.35
DorsaL Spryes.—Turkey Lake has on an average more dorsal spines, the
average being 14.52 for Turkey Lake and 14.23 for Tippecanoe Lakes. Fig. 3
represents the curves for this structure. The range of variation is the same, from
12to17. Although the average number of spines differs but slightly in the two
285
lakes, the preferences shown for a given number of spines are quite different.
In the Tippecanoe Lake specimens the preference is decidedly for 14. In the
Turkey Lake specimens the preference is for 15, although not so decided. From
Table IV and the curves, it will be seen that the number of individuals in Tur-
key Lake having 14 spines and 15 spines are about the same, 41 per cent. having
14 and 44 per cent., 15, while in Tippecanoe Lake this is not the case, 60 per
cent. having 14, and only 25 per cent. having 15.
70 p> : T
60 nM
50 ; :
40 Hatt at rt
: AY
30 , F
Tr i
tard
20 i
i i)
Hl .
104 7 :
o Hitt i ae
12°13 #14 «15 6 17
Fig. 3.
TABLE IV.
o
3
q
q g 5
4d | gBd
fsa | £ia
BAY | SHH
Per cent. of specimens having 12 dorsal spines............... 0.32 0.38
Per cent. of specimens having 13 dorsal spines............... 5.09 11.24
Per cent. of specimens having 14 dorsal spines............... 41.26 60.85
Per cent. of specimens having 14 dorsal spines............... 44,22 25.96
Per cent. of specimens having 16 dorsal spines............... 6.90 1.16
Per cent. of specimens having 17 dorsal spines............... 0.65 0.38
Dorsau Rays.—The average number of dorsal rays for Turkey Lake is 14.87,
for Tippecanoe Lake, 16.40, the latter having on an average almost two more.
The curves are given in Fig. 4. From this and Table V it will be seen that Tur-
key Lake specimens show a decided preference for 15 rays, while the Tippecanoe
Lake specimens show just as decided a preference for 16 rays, 52 per cent. of the
286
specimens having these numbers in both lakes. The range of variation is two
greater in Turkey Lake, from 12 to 18 as compared from 14 to 18 in Tippecanoe
Lake. This again may be due to the greater number of specimens.
60-7
ee
re
507
ipa
mete bee
Seegenae
- rT
fat ft
TABLE V.
42 ae
3 —
Ba [Beg
i o
ef | 285
ce ee
Per cent. of specimens having 12 dorsal rays................. O/B 2 lhcass Seomies
Per cent. of specimens having 13 dorsal rays. ................ PAS? el warms
Per cent. of specimens haying 14 dorsal rays................. 28.77 3.48
Per cent. of specimens having 16 dorsal rays. ...............- 52.26 31.78
Per cent. of specimens having 16 dorsal rays................4 12.16 52.3
Per cent. of specimens having 17 dorsal rays................. 1.64 15.11
Per cent. of specimens having 18 dorsal] rays................. 0.16 0.77
Table VI presents all the combinations of dorsal spines and dorsal rays from
both lakes. The spines are represented by Roman numbers and the rays by
Arabic numbers. The commonest combination in Turkey Lake is XITV-15 and
XV-15; XIV, XV, occurring most frequently in the spinous dorsal, and 15 most
frequently in the soft dorsal. The per cent. of specimens having these combina-
tions is 22.46 and 24.49 respectively. In Tippecanoe Lake, XIV-16 is the com-
monest combination, XIV being the prevailing number in the spinous dorsal and
16 in the soft dorsal. 32.11 per cent. of the specimens have this combination.
287
TABLE VI.
De) 4,0
Ba | Se
BY |Aass
ge | age
o o aH
Fy ey
Per cent. of specimens having the combination XII-14..... OIG Ne isinae
Per cent. of specimens having the combination XII-15..... OLB |e seecakes
Per cent. of specimens having the combination XII-16.....|........ 0.37
Per cent. of specimens having the combination XIII-14..... 0.84 0.37
Per cent. of specimens haying the combination XIII-15..... 3.71 2.22
Per cent. of specimens having the combination XIII-16..... 0.67 5.92
Per cent. of specimens having the combination MXIJI-17.....)........ 2.59
Per cent. of specimens having the combination XIV-12..... OWG becuse.
Per cent. of specimens having the combination XIV-13..... TOT). eitienciien
Per cent. of specimens having the combination XIV-14..... 11.99 1.48
Per cent. of specimens having the combination XIV-15..... 22.46 20.37
Per cent. of specimens having the combination XIV-16..... 5.74 | 32.11
Per cent. of specimens having the combination XIV-17..... 0.33 6.66
Per cent. of specimens having the combination XIV-18.....].... ... ARalal
Per cent. of specimens having the combination XV-13..... OBOE a ace wna
Per cent. of specimens having the combination XV-14..... 13.51 1.85
Per cent. of specimens having the combination XV-15..... 24.49 8.14
Per cent. of specimens having the combination XV-16..... 5.40 14.44
Per cent. of specimens having the combination XV-17..... 0.84 1.48
Per cent. of specimens having the combination XV-18..... OG Vices ees
Per cent. of specimens having the combination XVI-12..... ONG. ocsscne scenes
Per cent. of specimens having the combination XVI-18..... OTB) excavate
Per cent. of specimens having the combination XVI-14..... DOO: tots santa
Per cent. of specimens having the combination -XVI-15..... 3.04 1.11
Per cent. of specimens having the combination XVI-I16..... 0.84 0.37
Per cent. of specimens having the combination XVI-17..... O88 Vecie siavers
Per cent. of specimens having the combination NVII-14..... 0550 Vescesnes
Per cent. of specimens having the combination XVII-15.....]........ 0.37
Per cent. of specimens having the combination XVIJI-16..... ONG MN as oe sdssices
Per cent. of specimens having the combination XVIII-14..... OTB Wad acs ceges
In Table VIL is given the variation in the two dorsal fins taken together. The
average number for the two fins is 29.21 for Turkey Lake and 30 for Tippecanoe
Lake. In Turkey Lake 36.82 per cent. have the average number; in Tippecanoe
Lake, 41.8 per cent.
spinous dorsal and five for the soft dorsal] in Tippecanve Lake, and seven in each
The range of variation in the fins separately is six for the
dorsal fin in Turkey Lake. With an exception in the spinous dorsal in Tippecanoe
Lake the range of variation is, in each case, one greater for the two fins taken
together, than for the fins separately. Although the extent of variation is only
one greater for the two fins together, the per cent. of specimens having the aver-
age number is much smaller than the per cent. of specimens having the average
288
number in the fins separately. In Turkey Lake nearly 37 per cent. have the
average number of the fins taken together, while 44 per cent. and 52 per cent.
have the average number in the spinous and soft dorsal respectively. In Tippe-
canoe Lake 41 per cent. have the average number for both fins, while 52 per
cent. and 61 per cent. have the average number in the spinous and soft dorsals
respectively.
TABLE VII.
-) '
pe | 23
By |Feg
ge | gid
ee | aa
cy fe
Per cent. of specimens having 26 rays in the dorsals .......... 0533: Havers ees
Per cent. of specimens having 27 rays in the dorsals.......... 2.02 0.37
Per cent. of specimens having 28 rays in the dorsals.......... 16.38 4.07
Per cent. of specimens having 29 rays in the dorsals .......... 36.82 28.15
Per cent. of specimens having 30 rays in the dorsals.......... 32.59 41.80
Per cent. of specimens having 31 rays in the dorsuls .......... 9.28 22.22
Per cent. of specimens having 32 rays in the dorsals .......... 1.85 3.33
Per cent. of specimens having 33 rays in the dorsals .......... OR c¥aal ecwacnrem te
SUMMARY.
1. This species is equally abundant in the two lakes.
2. The color pattern of Tippecanoe Lake specimens shows. a greater affinity
for the primitive, simple Wabash River pattern than does that of Turkey Lake
specimens.
3. In Turkey Lake the nape is usually naked; in Tippecanoe Lake the
nape is usually scaled.
4. Tippecanoe Lake specimens have « smaller number of scales in the lat-
eral line.
5. The anal spines vary but little, and show the same variation in the two
lakes.
6. The anal fin is somewhat larger in the Tippecanoe Lake specimens.
7. Turkey Lake specimens have one more dorsal spine.
8. Tippecanoe Lake specimens have one more dorsal ray, 16 rays is the
mean in Tippecanoe Lake and 15 in Turkey Lake.
9. The combinations of the dorsal] spines and rays are determined by the
numbers that prevail in the fins separately.
289
10. The range of variation in the total number of dorsal spines and rays
combined is one greater than the variation in the fins separately.
11. The number occurring most frequently is 29 in Turkey Lake and 30 in
Tippecanoe Lake.
12. The preference shown for a given number is less decided for the two
dorsal fins taken together than for the dorsal fins taken separately.
18. The variation is in all cases continuous.
THE VARIATION IN TURKEY LAKE.
Many of the facts on the extent and character of the variation of the 600
specimens from Turkey Lake, taken as a whole, have been given in the pre-
ceeding.
The lengths of the 600 specimens from Turkey Lake were measured and upon
comparison were found to fall into three quite distinct groups. Fig. 5 represents
the curve for all. Each of the smaller horizontal] distances represents one mm,
and each of the larger verticle distances one per cent. The sizes ranged from 27
mm. to102mm. The first group ranges from 27 mm. to 60 mm.; the second from
60 mm. to 80 mm., and the third from 79 mm. to 103 mm, The three curves of
Fig. 5 represent these three groups. I have watched the growth during the first
summer, and know the first curve to represent the first summer’s fish. The second
curve in all probability represents the second year’s fish, and the third curve, those
three years old and over. The growth, thus, is most rapid during the first sum-
mer, the rate of growth decreasing each year after. The fish reaches practically
its full size the third year, though the more gradual slope to the right of the last
curve shows that it does not cease growing entirely.
o - men
}4 i AY
a
; 30 35 40 45 50 65 60 65 70 75 80 85 90 95 {00
Fia. 5.
290
Having grouped them into three definite ages, a summary of the characters
for each was made, and curves constructed. Figs. 6, 7, 8 and 9 represent the
curves for these characters. In all the curves constructed for these ages, the contin-
uous line is for the third year specimens, the broken line for the second year
specimens and the dotted line for the first year specimens.
LaterRAL Liye.— Below is the table of the average number of scales in the
lateral line of the three ages.
Ist year. 2d year. 8d year.
Rightside ig duccaneciashenaeeee geen yen wesrares 87.84 90.80 88.39
WMeftsid@s suucerseoecsdk wevvecens Meese es ees 88.00 89.80 88.78
From this it is seen that the first and third year specimens are most nearly
alike. The second year specimens have about two scales more. By reference to
the curves, Fig. 6, and Table VIII below, it will be seen that the great bulk
of the specimens of all three ages have from 85 to 92 scales. The increased
average in the second year is due to a larger per cent. having 93, 94, 95 and 96
scales than in the first and second years.
20 =
i
15 =a
STAN
WY ul
10 71 iN
Le |
: A
2 [ a
f/ wT pt
Wi 4 Lt
of ee
80 85 930 95 100
Fie. 6.
TABLE VIII.
“SO[B9Q TOL SUAV A
smeide Ss. go" “quay 19g
“SOTVO OL SUTALTT
SUaMIo9dg Jo "Judy 19g
"SO[BIG GG SULARTT
SUPTIINVdG Jo “4ueg 19g
40
OL. | vsscee
“"SOTBOG BG SULALTT
SuUsTTIDedg Jo "queD 19g
“SO[BO 1G SULABAL
susTIIIedg Jo *yUeH 19g
40 |...
‘soTvog 96 SULAT
smamdedg Jo yuan 1eg
102
81
“saTBOg CE SULAVT
suewooedg Jo yuan log
96
“Sd[VOQ FG SULAVHL
susttoedg jo -yuag log
*soTvog ¢6 SULAR
smeulaedg Jo -yuag log
2.47 | 2.86 | 3.68
“S9TVOQ 7G SULAC HL
suemmoodg fo yueg Log
"SOTVOG [6 SUIATH
sustloedy Jo quay 19g
9.87 | 8.58 | 5.57 | 4.20 | 8.86 | 4.29 | 4.29 |......]..c0.|ecceee| eevee
“SOTBOG 06 SUIACH
suomaedg Jo -yUaD 19g
“SOTBOG 68 SULARHL
suMaMIDedg Jo “yUuey 10g
“SO[VOG 9g SUIARTT
suoultoedg Jo "490 19g
*SOTBOG 1g SUIARH
suomloedg jo "yuan log
8.58 | 10.73 | 13.73 | 13.73
“SO[BOG 98 SULABH
suomtoedg jo ‘queQ log
“SO[BOG Cg SULALTT
susttoedg Jo -4uag 10g
3.84 | 9.97 | 18.45 | 11.52 | 15.38 | 15.38 | 5.69 | 4.50 | 1.99 | 4.50
“se[B09 Fg SULAC HT
suem1oedg jo "yUu9p 10g
36
“SOTBOG Og SUIABTT
suemoedg jo “yudD log
4
OM
+ | 1.22 | 2.04 | 7.35 | 10.24 | 11.47 | 12.28 | 15.57 | 11.06 | 14.34 | 3.67
“891809 7g SOLAR],
sueTAIDEdg Jo “yUaD 19g
96
42) 85 | 2.14 | 4.29] 7.72
“S0[899 [g SULAGT
SUGUIIDEdG Jo “yuoy 19g
85
*SOTBOG (0g ULAR
sustAINedg Jo "yu 19g
First yearspecimens| 1.99 |.........
Second year speci-
TONS -seeeesee seers
speci-
Third year
mens...
291
292
ANAL Frn.—Five out of 116 first year specimens have one anal spine; 6 out
of 236 of the second year, and 3 out of 246 of the oldest specimens.
The average number of anal rays are 10.56 for the first year, 10.74 for the
second year and 11.00 for the third year specimens.
The curves in Fig. 7 and Table IX, below, show that the anal fins of the first
and second year specimens more nearly resemble each other. All three ages show
a preference for 11.00 rays. The per cent. of specimens having this number are
51.69, 52.53 and 61.60 for the first, second and third year specimens respectively.
The per cent. of specimens having 10 rays is reduced from 36.43 in the first year to
20.57 in the third year, and the per cent. of those having 12 rays is increased
from 5.09 in the first vear to 20.16 in the third year. There is a very evident in-
crease in the number of spines with the age.
The extent of variation of the second and third year specimens is the same.
The first year specimens, although only half as many, exceed the other ages two
rays in the extent of variation.
n t { i
ae
60 aN
sor aa
inal Att
appt aaa
veechet FEF oHEE
ae iii val Mi
= ia jeeeesen eal
20 a
a
10 Fra a
ok Ey. Seyret nk SOR,
7 8 a jh Fb F213
Fie. 7.
TABLE IX.
First | Second | Third
Year Year. | Year
Per cent. of specimens having 7 anal rays.......... OS BFP eeu yape all eens Giaide
Per cent. of specimens having 8 anal rays..........]........ On eer eee
Per cent. of specimens having 9 analrays.......... 5.09 1.69 0.82
Per cent. of specimens having 10 anal rays.......... 36.43 82.19 20.57
Per cent. of specimens having 11 anal rays.......... 51.69 52.53 61.60
Per cent. of specimens having 12 anal says.......... 5.09 13.12 20.16
Per cent. of specimens having 13 anal rays.......... O84: fc cea 0.82
293
Several important facts brought out by the preceding comparison are worth
consideration.
1. No two of the ages here compared are alike ‘in all the characters.
2. In the anal fin and soft dorsal there is a definite increase in the number
of rays with the age.
3. Variation of this nature is not present in the other structures.
4. The extent of variation in the different ages is about the same.
DorsaLt Rays.—The average number of dorsal rays are 14.57, 14.76 and 14,98
for the first, second and third year specimens, respectively. There is a slight in-
crease with age. The summaries for this structure are given below in Table XI,
and the curves in Fig. 8. The prevailing number of rays is 15 for all three ages,
the per cents. being 53.39, 5253 and 55.69 for the first, second and third year
specimens, respectively. The percent. of specimens having 14 rays decreases from
40.72 in the first year to 22.35 in the third year specimens, while the per cent. of
specimens having 16 rays increases from 3.38 in the first year specimens to 16.73 in
the third year specimens. ‘The extent of variation is from 12 to 16 in the first
year, from 12 to 17 in the second year and from 13 to 18 in the third year speci-
mens. As in the anal fin there is a tendency toward a greater number of rays as
the fish grows older.
70
are a
t
+
ai
294
TABLE NI.
First | Second | Third
Year Year. | Year
Per cent. of specimens having 12 dorsal rays ........ 0.84 54k era citatas
Per cent. of specimens having 13 dorsal rays ........ 1.69 2.96 1.21
Per cent. of specimens having 14 dorsal rays ........ 40.72 30.50 22.35
Per cent. of specimens having 15 dorsal rays ........ 53.39 52.58 55.69
Per cent. of specimens having 16 dorsal rays ........ 3.38 11.48 16.73
Per cent. of specimens having 17 dorsal rays ........]........ 0.84 3.25
Per cent. of specimens having 18 dorsal rays ........|......../.....025- 0.40
DorsaL Sprines.—The averages for this structure are 14.69 for the first year,
14.39 for the second and 14.65 for the third year, the first and third years being
almost identical, and the second year having a fewer number. Fig. 9 represents
the curves for this structure. The curves of the first and third years are almost
identical, both showing a preference for 15, with about 35 per cent. for 14. The
second year shows as decided a preference for 14, about 35 per cent. for 15. This
structure varies from 13 to 16 in the first year specimens, from 12 to 17 in the
second year specimens and from 13 to 17 in the third year specimens. Table X
contains the summaries for this structure.
BEEQe
295
TABLE X.
First | Second | Third
Year. Year. Year.
Per cent. of specimens having 12 dorsal spines....]......... ONBE. brescenczows
Per cent. of specimens having 13 dorsal spines.... 1.69 © 8.47 3.65
Per cent. of specimens having 14 dorsal spines....] 38.98 49.14 36.17
Per cent. of specimens having 15 dorsal spines....| 50.00 35.16 51.62
Per cent. of specimens having 16 dorsal spines.... 7.62 5.50 8.13
Per cent. of specimens having 17 dorsal spines....]......... 0.42 0.40
The first and third year specimens resemble each other very closely in regard
to the scales in the lateral line and the dorsal spines. In these characters the
second year specimens show a decided difference. These have on an average two
more scales in the lateral line, and have 14 as the prevailing number of dorsal
spines instead of 15, the number in the first and third year specimens.
Several explanations might be suggested to account for a part or all of these
differences.
The explanation suggesting itself most readily is that an additional spine and
ray are added during the life of the individual. I have gone over all the specimens
carefully with this point in view, but find no evidence either of the splitting of a
ray or spine, or of the new growth of these, except at the anterior of the dorsal fins.
Here may be found numerous instances of shorter spines and rays from two-
thirds to one-fourth the normal length. But among so many specimens it is en-
tirely probable that these spines and rays would be found in every possible stage
of growth. But this is not the case. The spines and rays, although sometimes
only one-fourth the full length, are always strong and suggest aborted rather than
immature structures. Besides, if this were the case, we would expect to find the
tendency toward a lower number of spines, and rays very decided in the first
year specimens. While this condition is true in the dorsal and anal rays, it is
decidedly not true in the dorsal spines, where the characters in the first years are
almost identical with those of the third year.
Natura SELEcTION.—The principle of natural selection, the influence of
which upon this species I hoped in the onset of this work to find, can not be
applied in explanation of the difference in the number of scales and dorsal spines
without serious objections. If natural selection were the determining factor in
producing these differences, we should expect all the variations graduated with
the age. We would expect to have a narrower range of variation as the specimens
296
grow older. Neither of these conditions obtain. There are neither 18 dorsal rays
nor 13 anal rays represented in the second year specimens; and in the first year
specimens 17 dorsal rays are not represented. In the dorsal spines where the
difference is most pronounced we have in the first year specimens the exact
duplicate of that of the third year specimens, while the second year specimens
are quite different. The scales in the lateral line present the same difficulty.
ANNUAL VARIATION.—The explanation that seems to meet all the conditions
most satisfactory is that the species varies with the varying conditions of successive
years.
The difference in the dorsal spines of the different ages accounts thus for the
abnormality of the curve for the dorsal spines of all the Turkey Lake specimens,
Fig. 4. The 600 specimens for which the curve is constructed is a composite lot
of three age varieties.
This conclusion, however, should be held with some reservation. It will be
noticed that nearly all the curves of Figs. 7, 8 and 9 are abnormal curves, which
may possibly be due to the presence of local races in the lake. While this may
possibly be the case, it is not at all probable, because, in the first place, the
curve constructed for the dorsal spines of 100 specimens of three year olds,
taken within a distance of 100 yards along the shores where the conditions were
undoubtedly uniform, gave a curve identical with that for all the three year
olds. In the second place, the second and third year specimens are found in
about equal abundance together, and since these were promiscuously preserved it
is altogether probable that from any given locality, an equal number of each age
was taken.
The sex has been determined in all, and a summary shows that the sexes do
not differ in the characters entering into the above considerations.
Cornell University Library
QH 98.T9I6
WAAL
3 1924 003 070 822
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mann