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ZiH'i

THE CRAWFISHES OF THE STATE

OF PENNSYLVANIA

By Dr. A. E. ORTMANN

[Extracted from the Memoirs of the Carnegie Mitseum, Pittsburg, Pa., Vol. II., No. 10.]

)J

THE CRAA¥FISHES OF THE STATE
OF PENNSYLVANIA

Bv Di;. A. K. OKTMANN

<

[Extracted Iroiii tlie Mkmoiks ok thu Cakxe(;ik Misktm, Pittsburj;. Pa., ^'o]. II.. No. 10.]

CONTKXTS.

I'Ai.i;.
I. iNTKODirnoN : Scoi'K 1)1' W'nllK ; .MlCTlIODS ; AcKNOWr.EDGMEXTS .'MS

II. HisToiucAi. Review of our Systematic K.NowLEiifiE of the Crawfishes of

Pennsvevaxia 348

III. -MoRpiioMXJY AND C'horoi.o(;v of the Pe.nnsyi.vania Species ."^.^O

.1. General Remarks oSO

/>. Key for tiie Pennsylvania species 351

C, De.scription and Distribution of the species 352

1. Cambarus (Faxoniiis) limosus (Raf.) 352

2. Caiiiharus (Faxonins) propin(|uns (iir 358

'2a. Cambarus (Faxonius) propin(jnns sanljorni (Fax.) (cxlraliniital) 3G5

3. Camharus (Faxonius) obscurus Hag 369

4. Cambarus (Bartonius) bartoni (F.) 377

Ad. Cambarus (Bartonius) bartoni robustus ((jir.) 388

5. Cambarus (Bartonius) carolinus Er 394

(I. Cambarus (Bartonius) monongalensis Ortni 398

7. Cambarus (Bartonius) diogenes Gir 402

IV. EcOEOdV A.ND GeOGRARHICAE DISTRIBUTION 410

-1. Ecology 410

1. The River-S])ecies : C. limosus, pr()pin(iuus, obscurus 410

2. The Mountain-Stream Species : C. bartoni 4 I ."!

•">. The Burrowing Species : C. carolinus, monongalensis, diogenes 41 (J

II. General Habitat 4 1 (5

'6. Shape of Burrows . . . . , 418

r. Constniction of IJurrows 419

B. Geographical Distribution 425

1. Cambarus limosus ; . -125

II. Summary of facts 425

h. Origin of distribution 425

2. Cambarus propinquus, stinborni, and obscurus 433

a. Summary of facts 433

b. Origin of distribution 434

3. Cambarus bartoni 447

II. Summary of facts ' 4 47

iii

XV MEMOUJS OF THE CAliNEGIE MUSEUM

Page.

h. Origin of distribution 447

4. Canibarus bartoni robiistiis 44!i

a. Summary of facts 44!l

b. Origin of distrii)uti<)n 44!i

5. Cambarus carolinus 4 A 1

<i. Summary of facts 4-")l

I). Origin of distribution 452

6. Cambarus monongalensis 4")-"5

n. Summary of facts 45."!

h. Origin of distrilnition 454

7. C'ambarus diogenes 457

(I. Summary of facts 457

b. Origin of distribudoii 4511

8. Summary of studies on distriliiitinn AiVl

y . Life History 4of)

1. Cambarus obscnrns 47<i

2. Cambarus propinquus and C. j)ropinquus sanborni 47()

3. Cambarus limosus 477

4. Cambarus diogenes 4 Si)

5. Cambarus bartoni and ('. bartoni robiistus 4S()

6. Cambarus carolinus and monongalensis 4.S!»

YI. Economic Yauue 4!)2

1. Popular knowledge of crawfisbes 41t2

2. Tbe use of crawiishes as food and bait 4!K)

3. Crawfishes as scavengers ; their food ; their enemies 4!I4

4. Crawfishes as obnoxious creatures 41)ii

YII. BEARIXC4 OF THE ABOVE STUDIES OX THE ThEORV OF EVOTJTK IN "1!I7

1. The Mutation-Theory of I)e Yries 41)S

2. Species, Yarieties, and Yariations among the Pennsylvania Crawfishes 4iis

3. Formation of S])ecies by Isolation, as exemplified by Pennsylvania Crawfishes, 504

Bibliography 513

Explanation of Plates 518

MEMOIRS

OF THE

CAKNEaiE MUSEUM.

VOL. II. NO. 10.

THE CRAWFISHES OF THE STATE OF PENNSYLVANIA.
Bv .\knold E. Okt.m.wx, Fii.D.

I. Introduction.

Tliu present Memoir is a eontiimation of, and an enlargement upon, the prelimi-
nary paper published some time ago in the Annals of tlie Carnegie Museum (Vol.
HI, 1905, p. 387 et seq.) under the title "The Crawfishes of Western Pennsyl-
vania." The object of these publications is to furnish the student with an account
of the crawfish-fauna of the state of Pennssylvania as complete as possible, not only
from the morphological and zoogeographical, Imt also from the biological, ecolog-
ical, and economic standpoint. It is now believed that it is possible to present an
approximately complete report upon this important branch of the fresh-water founa
of the state, and in the prosecution of the studies of the author a number of (jues-
tions were raised, the solution of which proved to be highly interesting.

It may be well at the beginning to give an outline of the work done. At the
outset the writer resolved to go over the whole state, and to collect specimens in as
many different localities as possible. Very soon, however, it was discovered that
the different parts of the state are of unequal interest. Large tracts, located chiefly
in the central, northern, and northeastern parts of the state, proved to be rather
uninteresting, only one species of crawfish being present in them, while the western,
and chiefly the southwestern, and again the southeastern sections offered more
variet} . Thus it became necessary to pay more attention to the latter areas. The
uninteresting regions were entered only in a few cases, but a good deal of work was
done around their edges, in order to trace their limits as accnirately as possilile.

The location of the writer in Pittsburgh was advantageous, l)eing central within
that section of the state which dllintl the greatest number of problems. Most of

343"

344 MEMOIRS OF THE CARNEGIE MUSEUM

the colleeting excursions were undertaken witli Pittsburgh as a base. However, on
three occasions the base was sliifted. Visits were twice made to the eastern part of
the state, where the writer spent several weeks in September of the years 1904 and
1905 in Philadelphia and its environs, and once to the eastern central part, where
several days were spent in Harrisburg in June, 1905. The latter visit was marred
by rainy weather.

The work of collecting was done for tlie Carnegie Museum by the writer in con-
nection with his duties as Curator of Invertebrate Zoology, and all the necessary
expenses were paid by the Museum. In order to give an idea of the amount of
field-work done, a few statistics may be interesting.

Altogether one hundred and thirty-eight days were spent in the field, counting
only those days on which actual collecting was done : four days in 1903 ; sixty in
1904; and seventy-four in 1905. A few additional records were obtained in 1906.

The distances covered in travelling were as follows :

Total.
By rail, in 1904 3238 miles.

" " "1905 7579 " 10,817 miles

By team, in 1904 13 miles.

" " -'1905 26 " 38 miles.

On foot, in 1903 3 miles.

' 1904 173 "

" " "1905 209 " 385 miles.

Grand Total 11,240 miles.

Collections were made at about one hundred and fifty-six diflerent localities,
most of them in the state of Pennsylvania. Of the sixty-seven counties of the state
thirty-nine were visited.' Besides, visits were made to a number of localities situ-
ated in neighboring states, namely : in Camden County, New Jersey ; in Allegheny
and (iarrett Counties, Maryland; in [Morgan, ^Mineral, Tucker, Preston, Monon-
galia, Pleasants, AVetzel, Marshall, Ohio, Brooke, and Hancock Counties, West Vir-
ginia ; and in Harrison, Carroll, and Stark Counties, Ohio.

The material secured on tliese excursions Ijelongs to and has been dejjosited in
the collections of the Carnegie Museum, and comprises 303 entries in the Cata-
log, including 18fi9 specimens. But this does not represent the entire number of
specimens collected, since large sets, which have not been cataloged, have Iteen set
aside as material for exchange, studv, etc.

'Material wassecnred, seen, or was previously known from fifteen adiHtional counties, so tliat only thirteen are
not e.xploreil, namely : Carbon, Juniata, Lackawanna, Lebanon, .MifHin, Monroe, Montour, Pike, Schuylkill, Snyder,
Susquehanna, Union, and Wyoming. All these belong to the central and northeastern section of the state, where only
one species of Cambaru.s {C. bnrlimi) is to be expected, with the exception of those localities which are in th.e immediate
vicinity of the main branches of the Susqnehanna River, where also C. Vnwmis may be present (.Tuuiatii, Montour,
Snyder, and Union Connties).

OKTMANN: THE CRAWFJSUES OF THE STATE OF PENNSYLVANIA ;-545

Practical experience gradually revealed to the; writer the best method of col-
lecting crawfishes. At first the writer was rather inexperienced, and did not Icnow
where to look forcortnin species. But the necessary knowledge and skill were soon
acquired.

To collect the species living in streams, rivers, and ponds requires no special
effort ; it is only necessary to wade into the water-course to be investigated, or to
walk along its edge, and to discover the hiding-places of the crawfishes, which is
done by turning over stones. xV pair of rubber-boots, or wading-stockings, pro-
tected by ordinary bathing-shoes, is very convenient ; and also a small landing-net,
the bag made of minnow-netting. Frequently specimens may be caught with the
hand. In certain places, and in the case of certain species ( Caruharus liraoms) water-
weeds often furnish hiding-places, and here it is advisable to use a larger landing-
net with a long handle, which is pulled or pushed through the weeds.

JNIore work is required in collecting the burrowing species. The first thing is to
locate them, which is generally done by searching for the mud-cliimne3-s built over
their burrows. But it is not always easy to find these, particularly in late summer
and autumn, the chimneys being then rather inconspicuous. I generally first ascer-
tain favorable localities, such as swampy places in the bottom-lands, and springy
places on the hillsides. It is a vers' good plan to closely watch ditches by the road-
sides. Here the chimneys generally are easily detected, and in the neighborhood
of such places large colonies often may be found. After a burrowing form has been
located, the most difficult work begins, for the inhabitant of the burrow must be
dug out of its hiding-place. Care must be taken while digging not to injure
the crawfish. Sometimes the work can be done with the bare hand, but only in
those rare instances in which the burrows are in very soft ground. Generally the
work must be done with pick and shovel, but, as it is inconvenient to carry these
cumbereome tools along on an excursion and a gardenei''s trowel is a little too weak,
I have found a pioneer's bayonet, such as is used in the United States Army, to be
a tool which beautifully serves the purpose. These bayonets may be had in gun-
and ammunition-stores in the larger cities, and are practical!}' indestructible.

After locating a crawfish-hole, I begin to dig down art)und it, loosening the
dirt with the bayonet, and removing it with my hands, always taking care not to
lose trace of the hole. Generally it is necessary to'go down upon the knees (rubber
boots are useful here), and even the belly, in order to reach the bottom of the hole,
to which the crawfish usually retreats wluii disturbed. Often, however, it retires
to a side branch, in which case it is not necessary to dig so deep. As soon as it is
felt beginning to pinch with its claws, it is a sure sign that the crawfish has been

34G MEMOIRS OF THE CARNEGIE MUSEUM

cornered, and cannot retreat further. It is then readily secured, but care must be
taken not to pull it out l)y the claws, which may be easily broken off, thus damag-
ing the specimen. 'Jlie creature should be always seized by the carapace.

Sometimes this work is very difticult and tedious, and I have often been com-
pelled, chiefly in the case of (Aniiharas carol inus, to dig as deep as three feet before
succeeding in capturing the crawfish. In order to avoid unnecessar}' labor as far
as possible, I select burrows in which the water stands near the surface, refusing
those which evidently go for a long distance through dry soil, (ienerally there is
ample opportunity to choose between the numerous burrows of one and the same
colony of (■himnfv-l)uil(lers. Now and then it happens that the work is rendered
easier by the action of the crawfish itself. It occasionally comes to pass that, after
having disturbed the entrance of the hole by digging down far enough to reach the
water, the crawfish may be seen coming forward, apparently trying to ascertain the
the cause of the disturbance. This is a good chance to seize it, but one must be
quick, since it generally is the only chance to get it easily, although I remember
cases when the crawfish came out again and again, just so far as to be plainly seen,
but darted back at every attempt to seize it. Males ai-e more fi-ecpiently caught
in this way than females, and such captures are made most frequently in cloudy or
rainy weather. It is very rarely that thei'e is a chance to capture the crawfish at
the mouth of the undisturbed hole, when it is sitting at or near the top of the
chimney, or on the ground away from the hole. This happened only once or twice
in my experience.

1 have tried to discover means of compelling the crawfish to come out of its
burrow, but without much success. Bisulfide of cai'bon will not avail since it floats
uj>on water. I tried chloroform, which sinks in water, but without success. Only
once had I the satisfaction of driving a s[>ecimen of Ciiinhanis laoiinvf/aloisix out of
its hole by using unslacked lime. In this case I had dug a hole nearly three feet
deep without being aljle to reach the Ijottom. I liapj)ened to have with me, espec-
ially for this purpose, a small tin box with unslacked lime, and dropped the con-
tents into the hole, where it apparently sank to the bottom, ^^'ithin three or four
minutes the crawfish was discovered hurriedly working its way upward in the hole,
and was easily taken. This method, however, can be used only in a limited way,
since the holes generally are not straight enough to afford a chance to drop the lime
to the l)ottom, and, if the lime becomes lodged somewhere above the point where
the crawfish is staying, it drives it away fi-om the mouth of the hole, and eventually
kills it before it can be reached. (As to the use of lime for destroying crawfishes,
see infra, VI, 4.'*

ORTMANN: THE CRAWFISHES OF THE STATE OF PEMNSYLVANIA 347

The tools and the outfit needed for collecting crawfishes consist of rubber-boots
(for work in swamps), or wading-stockings with low shoes (for work in streams),
bayonet (for digging up burrowing species), and a landing-net with minnow-netting.
These are indispensable. Further, a number of collecting jars are needed, with 75
per cent, to 80 per cent, alcohol, and 1 i)refer to carry them in an ordinary fishing-
basket, l)ut any other portable receptacle will do. I do not recommend the use of
formaldehyde, since it makes the specimens too brittle. In order to take specimens
home alive, a so-called " bait-box " is most convenient.

I have no experience in baiting crawfish, and never attempted it, since the
methods described above proved satisfactory. Furthermore, I have never (in
Pennsylvania) used the seine, and I do not think that this would be necessary or
advisable in this part of the country, although it may be tried to advantage else-
where.

Besides the material secured l)y me in the manner above related, I made use of
the older material preserved in the Carnegie Museum, which was collected by the
following gentlemen : D. A. Atkinson, C H. Clapp, E. Frost, B. Graf, J. L. Graf,
E. Hays, S. N. Rhoads, A. T. Shafer. Q. T. Shafer. IT. II. Smith, R. Taylor, W. E.
C. Todd, M. A. Wertheimer, and E. B. Williamson.

I was aided in my re.searches by material kindly collected by various persons for
the ^luseum, while my work was in pj-ogress, and to all of them I wish to here
express my best thanks. They are the following members of the Museum staff:
Mrs. Elizabeth Courtney, Mr. C. V. Hartman, Mr. D. C. Hughes, Mr. O. E. Jen-
nings, and Mrs. O. E. .lennings.

The following gentlemen living in or near Pittsburgh furnishedimaterial : Dr. I>.
A. Atkinson, Dr. O. T. Cruikshank, Mi-. R. Dornberger, Mr. D. Friel, .Mr. !■; E.
Kelly. Dr. A. Koenig, j\lr. A. Settlemoyer, and Mr. R. Settlemoyer.

Material from other parts of Pennsylvania was received from Professor A. E.
Davison, Lafayette College, Easton, and Mr. H. Gera, Manaj'unk.

Specimens of our Pennsylvanian species were received from localities outside of
the State from the following sources: Academy of Natural Sciences, Philadel-
phia, (material from Delaware, ^Maryland, and North Carolina, in exchange); Mr.
H. Gera, Manayunk, (material from New Jersey); the late Mr. J. P.. Hatcher. Pitts-
burgh, (material from Iowa); Mr. O. E. .lennings, Pittsburgh, (material from Ohio);
^Ir. S. Prentice, Pittsburgh (material from Kansas); Dr. R. Ruedemann, Albany,
New York, (material from New York); Mr. F. Silvester, Princeton, New Jei-sey,
(material from iNIaryland): Mr. E. P.. Williamson, I'lulUon, Indiana, (material from
Kentucky, Indiana, and Michigan).

348 MEMOIRS OF THE CARNEGIE MUSEUM

Very considerable lielp was received from the Department of Agriculture in
?Tan-isl)urg. Tlie State Zoologist, Professor H. A. Surface, not only sent to me for
inspection all the crawfishes in the collection under his charge, but also submitted
to me material collected during the summer of 1905 by Mr. W. R. McConnell, who
was in charge of a survey conducted by the State Zoologist in cooperation with the
Commissioner of Fisheries, Mr. W. E. Meehan. To Mr. Meehan and Professor Sur-
ftice I am under special obligation for giving instructions to Mr. McDonnell regard-
ing the collecting of crawfishes, and to the latter gentleman for carrying these out
in the most thorough way in parts of the state not visited V)y myself

Finally, I was granted the privilege of examining the collections of the Academy
of Natural Sciences in Philadelphia, where I found, aside from older specimens
already used by Hagen and Faxon, valuable additional material, collected by
Messrs. H. A. Pilsbry, E. G. Vanatta, H. W. Fowler, and B. W. Griffiths. I also
received specimens for examination from Oberlin College, through the late Pro-
fessor A. A. Wright and jNIr. R. L. Baird ; from the New York State IMuseum
through Mr. F. C. Paulmier; and from Dr. P. R. Uhler in Baltimore, and Pi'ofessor
T. D. A. Cockerell, in Boulder, Colorado.

Last, but ncjt least, my thanks are due to the Directoi- of the Carnegie Museum,
Dr. W. J. Holland, who not only granted the means for carrying on my work suc-
cessfully, but has devoted much time to the editorial revision of the manuscript,
and helped me in the pi'eparation of the colored plates accompanying this memoir,
which were made under his direction.

II. Historical Review of our Svstematic Knowledge of the Crawfishes

OF Pexxsylvania.

The first species t)f the genus OimlKinis ever described very likely came from
our state. Astacus bartuni of Fabricius (1798, p. 407) was sent to its author by Pro-
fessor B. Smith Barton, wlio lived in Philadelphia, (see Faxon, 188o«, p. 65) and
presumably was collected in the neighborhood of that city.

The next record of a Pennsylvanian crawfish is given by Rafinesque (Nov., 1817),
Astacus limosus, from the muddy banks of the Delaware near Philadelphia. An-
other species mentioned Ijy Rafinesque from this state, Astacus fossor, is not recog-
nizable. Astacus limosvs from the Delaware River was described a month later
(Dec, 1817) by Say under the name of Astacas affinis.

Harlan (1835) mentions A. haiinni from the vicinity of Philadelphia, and this
record makes Philadelphia the type-locality of this species.

Girard (1852) gives the following new localities in Penn.sylvania : Cunibarus

ORTMANN : THE CRAWFISHES OF THE STATE OF PENNSYLVANIA 349

affinis = limosus, Schuylkill River at Reading, Bucks County; C. bartoni, Foxburg,
Clarion County; Cariisle, Cumberland County; Berwick, Columljia County.

In Hagen's Monograph (1870) no new species are added, although he doubtfully'
records (p. 100) C. obscurus from the state, but this was done under the erroneous
assumption that Aducus foasor of Rafinesque is the same as C. obscurios. Thus
Hagen's Monograph adds only a few new localities, namely : for C. limosus {affinis)
the Schuylkill River, Philadelphia, and Carlisle, Cumberland County. The new
locality ''Pittsburgh" for the same species is wrong.

The great revision of the genus published by Faxon (l<S85a) adds two species:
C. diogcnes from Derry, Westmoreland County, and C. rusticus from Pittsburg.
The latter record is incorrect, and should be dropped. Besides Faxon gives the fol-
lowing new localities: G. limosus, Brandy wine Creek, Chester County; Delaware
River, Bristol, Bucks County; Bainbridge, Lancaster County; C. bartoni, Bedford
and Pattonville, (see infra, footruote 16), Bedford County; Windham, Bradford
(bunty; Hummelstown, Dauphin County; Chester County ; Bainbridge, Lancaster
County; McKean County.

Thus only three species were known up to tliis date : C. limosus, C. bartoni, and
C. dio(jencs.

In 1898 Faxon added a louith species for the state, C. obscurus from Westmore-
land County, and also gave a new locality' for C. bartoni, Westmoreland County.

Williamson (1901) enumerated five species, and one variety from Allegheny
County, but, as has been tlcnionstrated by the writer (1905a), this is to be reduced
to four species and one vaiiety, of wliich the species recorded as C. dubius by
Williamson (C. raonon<jalensis Ortmann) is new^ for the state, as is also the variety V.
bartoni robustus Allegheny Count}' is for the first time cited as a locality for the
other species, C. obscurus (recorded as C. jii'ojiinqtius and rusticus), C. bartoui, and C.
dioijenrfi. Williamson's discoveries brought up the number of species known from
the state to five, and one variety, namely : C. limosus, ('. obscurtis, C. bartoni, C. bar-
toni robustus, C. mouougalensis (as dubius), and C. diojjenes.

In tlie i)rtliiiiiiiary report of the writer for western Pennsylvania, two other
species were added : C. propinquicsi'ron\ l'"i'ie and Crawford Connties, anil C. carol iuu.'<
from Fayette, Westmoreland, and Somerset Counties. Numerous new localities
were added to tliose already known. C. dubius of Williamson was recognized as a
species new to science, and described as C. mDUouijaJcnsis. The nunil»er of species
present in the state has not been increased by subsequent investigations, and stands
now as seven, with one variety, namely: Cambarus liuiosus (Rafinesque); C prop-
inquusGwiwdi; ('. obscurus Ilagen ; C. bartoni (Fabricius); C. bartoui robustus (Gmwd);
C. carolinus Erichson ; C. nujnougalensis Ortmann ; C. dioycncs Girard.

350 MEMOIRS OF THE CARNEGIE MUSEUM

These eight different forms are treated in the following pages, witli the addition
of one extralimital form, a variety of C. propinquas (C. prropnnqnu^i sdiiborni). The
recent and past ohservations made hy the writer, together with those collated frcjni
other sources, are presented as completely as possible in the succeeding pages, thus
giving a natural history of this group of animals, so far as found in the state of Penn-
sylvania. It has always been the aim of the writer to support his conclusions by
evidence secured within tlie state, but observations made oiitside of the state ai-e
sometimes introduced, where a gap was to be filled, or whei-e they were of special

interest.

III. MoRI'HOLOfiY AND ClIOROLOOY OF THE Pf.NNSYLVANIAN 8i'F,CTES.

^■1. General Remarks.

The crawfishes (as to the use of " ei'awfish " in preference to "crayfish" see infra,
VI) of the state of Pennsylvania belong to the genus (J(nnhara.'<- of Erichson (1846),
of the family Pufaiiiobiiehe Huxley, including the freshwater crawfishes of the north-
ern hemisphere. Faxon (1.S98) regards this as a subfamily, Amfaciurr, of the family
Astaciche, which also includes the subfomily, Pareisiaciiix of the soutlierii hemisphere,
now regarded as a family, rarastacidiv Huxley. There is some discussion as to the
proper name of the family, depending on the use of tlie generic name Astacvs Fab-
ricius, or of P(it(inu)I>i)(s Sainouelle, for the European crawfisbes. Tlie j)Osition ot
the writer was defined in 19(J2, {Proc. Amer. Philets. ibc. XLl, {). 276, footnote).
The question, however, has recently been finally settled by a discovery made by
Miss M. J. Rathbun {I'mc. Buil Si>r. Washington, XVII, HJOt, p. 170), but not in the
manner suggested by Miss Rathbun. The fact tliat the name Humarus was used
first by Weber [Nomenclatur EnUytnoloijicus, 1795), in ])lace of Astucus Fabricius, 1775,
makes Uom.anis a pure and simple synonym of Asfacus, and accoi'ding to the rule
" once a synonym, always a synonym," it remains a synonym. There is no reason
to make it " desirable," as Miss Rathbun expresses it, to set aside the rule in this case,

The genus Caniharns, containing now about 70 species, has been variously sub-
divided : by Girard (1852) into three groups; by Hagen (1870) likewise into three
group.s, which, however, do not exactly correspond to those of Girard ; and Ijy Faxon
(1885'() into five groups. Recently tlie present writer has <livided the genus into
six subgenera, namely : Paracarnharns, Procarabarus, Cambarus, Cambnrellu-^, Fa.ro-
nius, BarUinuis. (See Prac. Atn. Phil. Soc. XLIV, 1905, p. 91. ef .'^cq. ; .l/(7(. Cam.
Mils. Ill, 1905. p. 437; and Pmr. Wn.shingfui, Ac<tiL Sricin'e, VI II, p. 1, 1906.)

■^ Ericlison made this provisionally a subgenus, but e.xpre.sseil the opinion that it perhaps uould better rank as a
genus. Girard (1852) was the first to use Chmhiirus as a generic name.

ORTMANN : THE CliAWFISHES OF THE STATE OF PENNSYLVANIA 351

Only the two last named subgenera, Faxonius and Bartonius, are found witliin the
bijundaries of the state of Pennsylvania, and they are distinguished from the rest b}'
the shape of the male copulatory organs. The latter consist of two parts, which are
completely separated at the tips for a shorter or longer distance, and never possess
any accessory spines. The outer part in the male of the first form, (sexually ripe),
is almost completely transformed into a horny spine, while the inner remains soft.
1 11 the Pennsylvanian species of these two subgenera only the third pereiopods possess
a liook (used to take hold of the female) on the ischiopodite.

The two subgenera are distinguished as follows :
Subgenus Faxonius Ortinann.

Sexual organs of first pair in the male with two shorter or longer completely
separated tips. Tips straight or gently curved, divergent, parallel, or convergent,
generally rather slender.
Subgenus Baiionius Ortmann.

Sexual organs of the first pair in the male with two rather short, completely
sepai-ated tips. Both tips are strongly recurved, forming with the basal part about
a right angle.

B. Keij to the Boin.stjlvdnian Specie,'^ of the Goms Cdmbarus.

a'. Sexual organs of male of the Famniits-type. Rostrnm alwaj'S with a margioal spine on each side, and carapace
with one or more lateral spines. (River species.)
I/. Tips of sexual orjians short, straight, and divergent. Sides of carapace with several lateral spines anterior to,
and behind the cervical groove. (Delaware, Susquehanna, and Potom^ic drainages.)

C. (FajOHiM.1) limo8us (Rafinesque).
b". Tips of sexual organs long, almost straight, slightly convergent, or parallel. Sides of carapace with only one
spine behind the c- rvical groove,
e'. Rostrum with median keel. Sexnal organs of male of first form at anterior margin without prominent
angle (shoulder). Annulus ventralis of female flat. (Lake Erie and its drainage.)

C. {Fii-funiiin) propinqiiiis (iirard.

c". Rostrum without median keel. Sexual organs of male of first form at nnterior margin with a prominent

angle (shoulder). Annulus ventralis of female with two tubercles in anterior part. (Ohio drainage 1.

C. (Faxoniusj obscuru.^ Hagen. C^^l-
a' . Sexual organs of male of the Bartonius-type. Rostrum always without marginal spines. Carapace generally
without lateral spines,
i'. Areola wide. Form of carapace depressed. Color brownish or greenish. (Species of the small streams. )

C. (liarUmius) barloni (Fabricius). ff- ^If
1) ' ■ Areola narrow or obliterated in the middle. Form of carapace rather eompres-scil. ( Burrowing sjiecies. )

c'. Areola narrow. Inner margin of hand generally with only one row of tubercles. Color very bright, of
tints anusnal among crawfishes.
(/'. Color red. Kostram short and very broad. Outer margin of hand serrated. ( Mountains of southern

Pennsylvania). C ( /f'iWi/nii/.<) rnra/iHii.'i Erichson. f*"/

rf". Color blue. Rostrum shoit and narrower. Outer margin of hand rounde<l, not 8errate<l. (Mills of

southwestern Pennsylvania. ) C. (Barfo»iiu») iiiononjo/riuiw Ortmann. P. i? ^

352 MEMOIRS OF THE CARNEGIE MUSEUM

c" . Areola generally obliterated in the middle, or extremely narrow. Inner margin of hand with several
rows of tubercles. Color greenish or brownish. Rostrum rather long and narrow. (Swamps on hills
and in lowlands, southwestern and eastern Pennsylvania.) C. (Buitniiius) diogenes Girard.

C. Description and DistrUyut'ion of the Specicfi.

1. (Jambarus (Faxonius) limosus (Rafinesque).

(Plate B, Fig. 3; Plate XXXIX, Figs. 5fl. and 5h.)

Aslacns limosus Rafinesque, 1817, p. 4 .

Ashivtis nffinis Say, 1817, p. 168 ; Harlan, 183.5, p. 230, fig. 2 ; DeKay, 1844, p. 23 ; Gibbes, 1850, p. 195 ipartim).

J.s^ic'Ms 6(((7()«/ Milne-Edwards, 1837, p. 331 (now Fabricius).

Cambariis affinis Girard. 1852, p. 37 ; Hagen, 1870, p. (10 ; PI. 1, figs. 19, 22, 84, 85, PI. 3, fig. 152, PI. 5 ; Abbott, 1873,

p. 80 ; Smith, 1874, p. 638; Faxon, 1881J, p. 146 ; Fa.xon, 1885^, p. 86 ; Fa.xon, 188.5//, p. 360 ; Underwood, 1886,

p. 366 ; Faxon, 1890, p. 628 ; Hay, 1899, p. 960, 964 ; Andrews, 1894, p. 165.
Cumbarus pealei Girard, 1852, p. 87.
Cambnrus (F<i.rn7ihis) limosus Ortniann, 19056, p. 107, 112, 131.

Body robust, puliescent all over, but chiefly so on carapace and chela?; but the
pubescence wears off easily, and in old individuals, especially in early spring, the
body is more or less hairless. The hairs are most persistent on the fingers of the
large chelfe.

Carapace subovate, depressed, the depression being brought about l)y a bulging
out of the brancliial regions. Tlie vertical lieight of the carapace, at a point ab<jut in
the middle of the gastric region (measured from this point to a point on the sternum
just in front of the first jiereiopods), the vertical height of the carapace at a point ot'
the areola directly above the sternum between the second pereiopods, and tlie great-
est width of the carapace at the hepatic regions are about the same; while the great-
est width of the carapace at the Ijranchial regions is distinctly greater. Rehition
G : H: 11 — I A : 1.2 to 1.4.^ The greatest width of carapace (at branchial regions)
is well behind, at about the middle of the branchial regions. The whole carapace
appears rather flattened dorsally.

Cervical (jroove deep, continuous on the sides. Anvhi about half as long as an-
terior section of carapace (including rostrum). Relation of (( :^; = 1 :0.40 to 0.55.^
Areola rather broad, relation of /r : / = 1 : 4.0 to 5.4,'' with aljout 5 irregular rows of
punctures.

Rostrum long and broad, reaching to the middle of the fifth joint of the peduncle
of the antenna, and to the end of the peduncle of tlie antennula. rarely slightly

3G= vertical diameter at gastric region; /f= transverse diameter at hepatic region; 7? = transverse diameter at
branchial region.

*a^ anterior, p = posterior section of carapace.
5 10 = width, I = length of areola.

ORTMANN: THE CRAWFISHES OF THE STATE OF PENNSYLVANIA 353

longer. Surface deeply concave, margins elevated and thickened, almost straight,
very little convergent toward the marginal spines. Mai-ginal spines well developed.
Acumen long, triangular, acutely pointed, about one third as long as the whole ros-
trum, sometimes slightly shorter or longer. Post-orbital ridges parallel, ending in a
sharp spine anteriorly.

Surface of cara;pace finely punctate, and very finely granulate on the sides in old
specimens. Sides spinose. There are a number of larger and smaller spines on each
side on the hepatic region, and a few spines are found on the branchial region
immediately behind the cervical groove, of which one is generally much larger than
the others. (In most cases there are two distinct spines, one above the other, the
lower one the larger.) All the.se spines are well developed only in larger individ-
uals; in young ones only two spines behind the cervical groove and one spine on
the hepatic region are present, l)ut tliese are visible even in the smallest specimens
at hand (25 mm. long). E.vternal orbital angle not marked, rounded off. Branchio-
stegal spine sharp and distinct.

Abdomen longer than the carapace, slightly narrower than the carapace in the
male, sliglitly wider in the female. Antei-ior section of telson on the outer posterior
corners generally with two spines, but there may be from one to three ; the num-
ber of spines may differ on either side. Posterior section of telson semicircular,
slightly wider than long, and slightly shorter than anterior section.

Epistoma with posterior part short and broad, almost three times as wide as long,
not plane, with a transverse groove posterior to the middle, and an anterior median
depression ; these are often united into a triangular or arrow-shaped depression.
Anterior section constricted at base, its anterior margin almost semicircular, with a
small median point, sliglitly varying in shape (sometimes it is subtriangular, some-
times the anterior point is ol)SCure), but its transverse diameter is always slightly
greater than the longitudinal.

Antennula with a sharp spine on the lower margin of the basal joint.

Antennal i^edunde with a sharp spine on the outer side of each of the two basal
joints.

Antennal scale long, as long as the rostrum or even slightly longer, reaching to the
middle or the end of the terminal joint of the antennal peduncle. Outer margin
with a strong spine. Laminar part rather broad ; its margin more or less regularly
curved ; the broadest part is in the middle or slightly anterior to it.

Flai/ellum, when laid backward, reaching to the fourth or even to the middle of
the fifth abdominal segment in the male ; in the female it generally does not reach
beyond the posterior margin of the third segment.

354 MEMOIRS OF THE CARNEGIE MUSEUM

First pereiopods comparatively short, and not very stout, considering the size of
the species. Hand short and not very broad, depressed, elongate-ovate, stronger
and more elongate in the male than in the female. Surface punctate. Inner mar-
gin almost straiglit, with a double row of tul^ercles, which are more or less spiniform.
Outer margin smooth, bluntly angular, more distinctly so distally. Fingers dis-
tinctly longer than the palm (measured from articular tultercle on upper .side of
carpopodite to articular tul)ercle on upper side of palm at liase of movable finger),
straight, cutting eilges straight, in contact all along their length, with a few very
small tubercles in the proximal part, for the rest without teeth or tubercles, but
•with a .short and dense pubescence, becoming slightly barbate proximally on lower
side. Upper surface of each finger with a low longitudinal rib, most distinct dis-
tally. Lower surface of hand almost smooth, sparsely punctate.

Carpopodite slightly longer than wide, shorter than palm, punctate. Upper
surface with a distinct longitudinal sulcus. Iimer margin with a strong procurved
spine in the middle, and a small spine anterior to it. Lower surface with two
strong spines, one in the middle of the anterior margin, the other at articulation
with hand. Sometimes there are additional small spines or spiniform tubercles,
proximal to, or above, the large spine of the inner margin.

Meropodite smooth, upper margin with two (rarely more, up to four) strong
spines at a short distance from the distal end. Lower margin with two rows of
strong spines, the inner one consisting of four to ten spines, largest distall}', the
outer one of two to three spines. A spine at the outer articulation with the
carpopodite.

IsoMopodite of third pereiopods hooked in the male; hook in the male of the first
form strong, subconical.

Coxopodites of posterior pereiopods without prominent crests or tubercles in the
male.

Fird plcopods of male of the first form (Plate I, Fig. 5a and oh) rather strong and
short, not reaching beyond the anterior margin of the coxopodites of the third
pereiopods. They are not articulated at the base, straight, and the two jsarts are
separated at the tips only for a short distance. Tips crossed (twisted), divergent;
that of the inner part is soft, gradually tapering to a point, and is directed obliquely
outward ; that of the outer part is horny, gradually tapering to a point, and directed
obliquely forward and slightly inward.

In the male of the second form the first pleopods are articulated at the base
when young, but not articulated when old, and both tips are soft ; that of the outer
part is rather bluntl}' pointed.

OKTMANN: THE CRAWFISHES OF THE STATE OF PENXSYl.VANIA 355

Annulus ventralis of female transversely rhombiform, with a short transverse
groove slightly posterior to the iiiidclle, and an S-shaped longitudinal fissure. An-
terior to tlie central groove there is on each side of the fissure a strong, tuberculi-
forni elevation, so that the fissure is situated in a rather deep depression. Posterior
to the central groove;, theiHs is a slight elevation, over which the fissure passes. The
annulus, consequently, appears trituberculate, the two anterior tubercles being
stronger than the posterior. In young females, the tubercles are only slightl}' de-
veloped, and generally the posterior tubercle is almost obsolete.

Size. — Rafinesque gives as total length 3-9 inches. The maximum, U in., = 229
mm., seems ratlier strange, since no such specimens have ever been subsequently
seen, even if we infer that Rafinesque intended the whole length, including
the claws. Hagen (1870, pi. 5) figures a very large female, which, including the
outstretched claws, would not be longer than about 7 inches (178 mm.). Its body
from the tip of the rostrum to the end of the telson, is 132 mm. long. The maxi-
mum length given by Hagen in the text (p. 61) is 4.7 in., = 119 mm; thus this
figure, altliough said to be of natural size, is apparently somewhat enlarged.

The largest specimens ever seen by the writer are in the museum of (Jberlin
College from the Potomac River, a female measuring 120 mm., and a male of the
first form measuring 105 mm. The largest specimen from Pennsylvania I possess,
is a female fron) the Delaware River at Torresdale, and measures 93 mm. in length;
the largest male (first form) is from the Delaware at Penns Manor, measuring 75
mm. in length. A male of the second form from Holmesburs; is 85 mm. lonsr.
Specimens over 100 mm. long, mentioned by the writer, (1899, p. 1210), as from
Philadelphia, are from the New Jersey side of the river, near Camden.

Colors. — (Plate B, Fig. 3. ) An account of the color of this species has been given
by Faxon (1885a, p. 88). It runs thus: " Upper surface greenish, mottled with
darker green, especially on the chelae ; tips of fingei-s orange, preceded by a dark
green ring, which runs along the outer border of the hand to the wrists; abdominal
somites ornamented with interrupted transverse chestnut-colored double bands.
Under surface of a lighter hue."

1 have repeatedly made notes from live specimens, and have found that the
shades of color vary greatly, although the general pattern has l)een correctly
described l)y Faxon. The general color of the body may be described as olirc-<jrcen
(Ridgway, 1^8(;, X, 18)", but it varies toward tuini;/-olire (III, 17), and olirc-i/cllow
(VI, 16). The sides of the carapace are generally lighter, of a whitish green.

'In the description of colors, I have used licrc (and in tlie following species) the nomenclature of IJidnway (1886),
and the Roman and Arabic numerals refer to his plates and figures.

356 MEMOIRS OF THE CARNEGIE MUSEUM

There is a brown {cJicstiiuf, \V, 9) spot on the anterior margin of the carapace on
each side below the eyes, not noticed by Faxon. The brown bands of the abdomen
are hwnit sieniiu [IV, 6). In the middle of the abdomen the epimera are hazel (IV,
12). The color of the hnger tips is ferrugineous (IV, 10), often paler, the preceding
band is dark olive-green, often almost black. The articular tubercles on the lower
side of the hand are taimg (V, 1), on the upper side they are darlc-green. The
articular membranes of the chelfe are ■w'mepui'jdc (VIII, 15). The darker green of
the carapace is generally confined to distinct large blotches, symmetrically disposed ;
one pair on the gastric region, and one each t)n the anterior and the posterior part
of the brancliial regions. ( Jften the two blotches of the gastric region run together,
which may also be the case with those of the branchial regions. They often appear
spotted or mottled with the lighter, or rather more l)rownish (tawn}' olive), ground
color. The brown spot on the anterior margin of the carapace is sometimes indis-
tinct, and in young specimens with fresh shells, it may have a trace of yellow
below. All these colors are bright and distinct only in fresh shells. On old shells,
a coat of mud is generally deposited, giving to the whole body a dirty blackish
color, and besides, the colors themselves fade considerably, so that only a dirty olive-
green remains, with some brown on the abdomen.

The color of neAvly laid eggs under the abdomen of the female is olive-green (X,
18).

The above description is founded upi)n the examination of one hundred and
twenty-one specimens, now preserved in the collections of the Carnegie Museum.
Fifty-six of these specimens are from the state of Pennsylvania, fifty-four from
New Jersey, eight from Maryland, and three from West Virginia (Potomac River
at Cherry Run, Morgan County). This, however, does not represent the total num-
ber of specimens seen by the writer, since many others were collected by him, as
well as seen in the collections of the Department of Agriculture of Pennsylvania, of
the Academy of Natural Sciences in Philadelphia, and of Olierlin College.

DISTRIBUTION.'

LOCALITIES REPRESENTED IN THE COLLECTIONS OF THE CARNEGIE

MI'SEUM.

Pennsylvania : Bucks Co., Delaware River, New Hope ; Delaware River, Penns
Manor; Little Neshaminy Creek, Grenoble ; ComnKjn Creek, TuUytown ; J'hihi-
delphia (Jo., Delaware River, Torresdale Fish Hatchery, Torresdale ; Delaware

' All localities without ttirtlier record have been ascertained by the writer in person. In other cases the authority
(when published), or the collector and institution, where the specimens are preserved, is given.

ORTMANN : THE CRAWFISHES OF THE STATE OF PENNSYLVANIA 357

River, I lolinesbiirg, (11. \V. Fowler coll., exch. Acad. Pliil. Nat. Sci.); Schuylkill
Canal, Manayunk ; Montgomery Co., Schuylkill River, West Manayunk, (H. Gera
coll.) ; Delaware Co., Marcus Hook Creek, ]Marcus Hook ; Franklin Co., Back Creek,
Williamson; Bedford Co., Raystown Branch of Juniata River, Bedford (A. Kcenig
coll.).

New Jersey : Camden Co., Delaware River, Camden ; Delaware River, North
Cramer Hill ; Mercer Co., Stony Brook, Princeton ; Delawaro-Raritan Canal,
Aqueduct near Princeton.

Maryland : Alleghany Co., Potomac River, Wiley's Ford, South Cuml)erland.

West Virginia : Morgan Co., Potomac River, Cherry Run.

PREVIOUS RECORDS.'

Type locality : Delaware River, Philadelphia, (Rafinesque).

Pennsylvania : Schuylkill River, Philadelphia, (Hagen) ; Bucks Co., Bristol,
(Faxon) ; Berks Co., Schuylkill River, Reading, (Girard) ; Chester Co., Brandy-
wine Creek, (Faxon); Tributary of Brandywine Creek, Chadds Ford Junction, (Ort-
mann) ; Lancaster Co., Bainbridge, (Faxon) ; Cmnherland Co., Carlisle, (Hagen) ;
Adams Co., Gettysburg, (Ortmann).

New Jersey : Camden Co., ('amden, (Faxon) ; Burlington Co., Burlington,
(Faxon) ; fiercer Co., Trenton, (Abbott) ; Monmouth Co., Red Bank. (Fa.xon) : Morris
Co., Schooley's Mountain, (Faxon).

Maryland: Cecil Co., (Faxon); Hartford Co., Havre de Grace, (Hagen) ; Balti-
more Co., Baltimore, (Andrews); Guynn's Falls, (Faxon); Druid Hill, (Faxon); Anne
Arundel Co., (Faxon) ; Charles Co., (Faxon) ; Montgomery Co., (Faxon) ; Washington
Co., Williamsport, (Faxon) ; Alleghany Co., Canal four miles south of Cumberland,
(Faxon).

District of Columbia : Washington, (Girard).

Virginia : Fairfax Co., Gunston, (Faxon) ; Augusta Co., Shenandoah River,
Wayne-sboro, (Faxon)* Isle of Wight Co., Blackwater River, Zuni, (Faxon).

NEW LOC.VLITIES NOT REPRESENTED IN CARNEGIE MUSEUM.

Pennsylvania: Montgomery Co., Roberts Run, Abranis, ( B. W. Griffiths it 11.
W. Fowler, coll., Acad. Nat. Sci., Philadelphia).

Tlie following records are from the collections of .Mr. W. K. .Me(/ounell, belong-
ing to the Department of Agriculture, Harrisburg : Yellow Breeches Creek, New
Cumberland, Cumberland Co.; Conedogwinet Creek, West Faii'view. ( 'uniberland
Co.; Sherman's Creek, Landisburg, Perry Co.; Montour Run, (ireeiipark. Perry

*A number of doabtful records have been dropped fsee Ortmnnn, 1905/i, p. 131). Too geneml records are also
omitted, for instance : "Susfiiiclinniia River, Fa., ( Fa.\on\" since just in this case more exact information is desired.

358 MEMOIRS OF THE CARNEGIE MUSEUM

Co.; Susquehanna River, Northumberland, Northumberland (Jo. ; Fishing Creek,
Bloomsburg, Columbia Co. ; Bald Eagle Creek, Milesburg, Center Co. ; Conooo-
cheague Creek, Chambersburg, Marion, and Williamson, Franklin Co. ; Maiden
Creek, Maiden Creek, Berks C'o.

REiNIARKS.

Camharus limosvs is the common river species of eastern Pennsylvania. Its
morphological characters are very constant, and give it a rather isolated position
within the genus, which is also expressed by, and very likely due to, its geograph-
ical isolation, the most closely allied species being found far to the west, in Indiana
and Kentucky, (see Ortmann, 1905//, p. 114, 127). The most prominent specific
chaj-acters are furnished by the male sexual organs, and the .spinosity of the sides
of the carapace. The description, as given above, does not indicate any important
variations, and the specimens are generally very uniform. The spino.sity of the
carapace, however, changes with age, yoving specimens being much less spinose than
old ones. In the spines of the chelipeds and of the anterior section of the telson,
there is some variation, but this is only slight and not subject to any rule. The
shape of the carapace and rostrum is very constant, the only differences of age no-
ticed are found in the acumen of the rostrum, which in young specimens is slen-
derer than in those which are older, and in the bulging out of the branchial regions
of the carapace, which is most marked in old individuals. The changes in the
pubescence of the wbole body are apparently due t(j wear. The short hairs gener-
ally present in newly moulted individuals slowly wear off, and specimens with a
distinct coat of dirt upon them, indicating age, generally have the pubescence more
or less, sometimes entirely, worn off. Only on the hands and fingers are traces of
it left.

I niN'self have never found any freaks in this species. But Mr. W. R. jMcl.'oimell
found a male (first form), 66 mm. long, at Bloomsburg, Columbia County, (the only
specimen taken at this locality), in which the rostrum had two pairs of marginal
s[)ines. Tlie additional pair in this specimen is smaller, and stands about midway
between the normal pair and the base of the rostrum.

2. Cambarus (Faxonius) i'kopixquus Girard.
(Plate XXXIX, Fig. 6a and 66.)

C:inilmnis pni/iimpius, Uiiard, 1855, p. 88 ; Hagen, 1870, p. 67, PI I, f. 3-1-38, PI. 3, f. 1.j3 ; Siiiitli, 1874, p. 638 ; Forbes,
1876, p. 4, 19; Bundy, 1877, p. 171 ; Bumly, 1882, p. 181 ; Biinily, 1883, p. 402; Faxon, 1884, p. 147 ; Faxon, 1885.i,
p. 91 ; Faxon, 188oh, p 360; Underwood, 1886, p. 371 ; Faxon, 1890, p. 628 ; Hay, 189G, p. 497, Fig. 11 ; Ward,
1896, p. 15 ; Faxon, 1898, p. 651 ; Hay, 1899, p. 960, 962 ; Ortmann, 1905(i, p. 400.

C'unbarus (Faxonius) pnijiini/Kus OrtmanVf 150r56, p. 112. 132.

ORTMANN: THE CRAWFISHES OF THE STATE OF PENNSYLVANIA 359

Bochi not very rol)nst, not pubescent, with only a few, scattered, short hairs,
chiefly on the chehe, but the hair wears off very soon, and the body becomes smooth,
with exception of a sh'ght pubescence at the base of the cutting edges of the fingers.

Carapace subovate, depressed. ReUition G: H: B — \ A -.1.2 or 1..3. (The widtli
of the branchial regions appears slightly less than in G. liviosus, but tins is probably
due to the fact that the specimens of C. lywpinquus at hand are rather small).
Greatest width of brancihial regions well behind, at al)out the middle of the bran-
chial regions. Carapace flattened dorsally.

Geroical groove deep, more or less distinctly interrupted on the sides just above
the lateral spine. Posterior .section of carapace about half as long as anterior (rela-
tion a :^j = 1:0.42 to 0.62.

Areola rather broad, tu:l = 1:4.7 to 6.0, with about four irregular rows of
punctures.

Ro)<tnnu long and broad, reaching to the middle of the fifth joint of the peduncle
of the antenna^and to the end of the peduncle of the antennula, sometimes slightly
shorter. Surface concave, with a more or less distinct, low. longitudinal median
keel toward tlie tip. Margins elevated, but not much thickened, straight, more or
less convergent toward the marginal spines. Marginal spines generally well devel-
oped in young specimens, less so in older ones, sometimes quite small. Acumen
long, triangular, comparatively longer in young specimens, pointed, about one-third
as long as the whole rostrum, or shorter. Postorbital ridges slightly divergent pos-
teriorly, ending anteriorly in a moi-e or less distinct small spine.

Surface of carapace finely j)unctate, and slightly granulate on the hepatic regions
in old specimens. Sides witli only one spine on the branchial regions, immediately
be]iin<l the cervical groove. This spine is always present and sharp, but generally not
very large. No other spines on the sides of the carapace. External orbital angle not
marked. Branchiostegal spine small, but sharp, or tuberculiform, or even obsolete.

Abdomen longer than carapace, slightly narrower than the carapace in the male,
about as wide as the latter in the female. Anterior section of telson on the outer
posterior corners with one to three spines (two spines is the general condition).
Posterior section of telson semielliptical, considerably wider than long, and slightly
shorter than anterior .section.

Kpisto'ina with posterior part short and broad, almost three times as wide as long,
not plane, with a ti'ansverse groove and an anterior median depression running into
each other. .Vntt'rior section constricted at base, its anterior margin generally almost
semicircular, witli a median point and an indistinct angle on i-aeh side, but shape
rather vavial)U': sometimes it is truncate anteriorlv, with or without median point.

360 MEMOIRS OF THE CARNEGIE MUSEUM

tlie latei-al angles being more ilistinct. Its transverse diameter is slightly greater
than the longitudinal.

Antcnnula with a distinct, sharp spine on the lower margin of the basal joint.

Anfennal pedunc/e with a distinct spine on the outer side of the first joint, and a
smaller, sometimes tuberculiforin spine on the second joint. Anfennal scale long, as
long as i-ostrum or slightly longer, reaching to the middle, or almost to the end of
the terminal joint of the antennal peduncle. Outer margin with a strong spine.
Laminar part rather broad, almost semicircular, the broadest part is slightly anterior
to the middle.

Flagellwin reaching to the beginning of the fifth abdominal segment in both the
male and tlie female.

.First pereiopods not very robust, comparatively longer in the male, shorter in
the female. Hand elongate-ovate, depressed, moderatelj^ wide. Surface punctate.
Inner margin almost straight, with a double row of tubercles. Outer margin
smooth, marginated and bluntl}' angular, but almost evenly rounded near the
proximal end. Fingers longer than palm, almost straight in the female, and meet-
ing all along their edges ; in the male, the fingers are slightly gaping at the base,
and the movable one is slightly curved in the shape of an " S," which curve is chiefly
noticeable along the outer margin. Outer margin of movable finger slightly tuber-
culate at base. Cutting edges with a few small tubercles near the base, for the rest
slightly pubescent. Upper surface of each finger with a low, longitudinal rib.
Lower surface of hand sparsely punctate.

Carpiopodifc slightly longer than wide, shorter than palm, punctate, and with a
longitudinal sulcus on upper side. Inner margin with a strong, slightly procurved
spine in the middle ; generally there is a tubeix-le (rarely spiniform) anterior to
this spine. Lower surface with a low and broad tubercle in the middle of the
anterior margin, which is very rarely subspiniform ; a similar tubercle with a
spiniform tip at the articulation with the hand. No othei- spines or tubercles on
the carpododite, except that sometimes there is a small tubercle at the proximal
end of the inner margin.

3Ieropodite smooth ; upper margin with two small, often indistinct, or tuberculi-
forin, spines near the distal end. Lower margin with two rows of spines; the outer
row consisting of only one, rarely of two, spines ; the inner row consisting of a large
distal spine, and a number (up to seven or eight) of very small ones, which may be
entirely absent. Thus there are often (jnl}' two antei-ior spines present, representing
the di.stal spine of each row. A small spine at the outer articular tubercle with
carpopodite.

ORTMANN : THE CRAWFISHES OF THE STATE OF PENNSYLVANIA 361

Ischiopodife of tliird pereiopod hooked in the male, the hook in the male of the
first form being strong, subconical.

Coxopodltes of posterior pereiopods without prominent crests or tubercles in the
male.

First pleopods of male of the First fjrin (Plate XXXIX. Fig. 6a) slender, but
rather short, hardly reaching beyond the middle of the coxopodites of the third
pereiopods. They are not articulated at the base, and tlie two parts are completely
separated at the tips for a rather considerable distance (al)out one third of the
length from the inner Ijasal tubercle to the tip). Both parts are almost parallel,
only slightly convergent at the tips, which is due to a very slight curve of the outer
part. Outer part gradually tapering from base to tip, horny. Inner part soft, of
about the same shape as the outer, and of the same length, gradually tapering to
an acute tip. Hoth parts are slightly twisted, so that the tip of the outer is directly
anterior to that of the inner. Anterior margin of this organ without shoulder
shortly below the point of separation of the two parts; sometimes, indeed, there is
a slight notch, but never a sharp shoulder.

In the male of the second form, the first pleopods (Plate XXXIX, P^ig. Gh) are
articulated at the base when young, (only young specimens are at hand); both parts
are separated only foi- a short distance, and are soft; the outer one is rather
blunt, while the inner one tapers to a point. No notch or shoulder on anterior
margin.

Amiulus ventralis of female transversely rhombiform or ovate, rather Hat, very
slightly depressed in the middle, with an S-shaped longitudinal fissure. No tuber-
cles on anterior part. In young females, the median depression is very indistinct,
and the annulus is almost completely Hat.

iSize. — Hagen gives 2.6 in. = 66 mm. as the maximum length for this species. The
largest individuals from the state of Pennsylvania observed by the writer, arc a
male (first form) from Albion, Erie County, 61.5 mm. long, and a female from the
same locality 69 nmi. long. I have seen, however, two larger males (first form)
from Lake Erie, off the shore of Lorain ( 'ounty, < )hio (Mus. Oberlin), one measuring
77 mm., tlic other 81 www. in Ici.gth. Nevertheless, this seems to be one of the
smaller species, for in the streams running to Lake Erie in IVnnsylvniiia a consider-
able number of intlividuals have been taken, none of whicii was longer than the
above mentioned specimens.

Colors. — The colois of this species agree closely with tho.se of C ohscurus (which
see for further particulars). The following notes were taken from an adult female,
collected on the shore of Lake P]rie at Miles ( h-ove.

362 MEMOIRS OF THE CARNEGIE MUSEUM

General color, oUve-grccn (Ridgway, 1886, X, 18), sides of carapace cream-color
(VI, 20). A rufous (IV, 7) spot on anterior margin of carapace. Lower side
whitisli. Anterior half of abdominal segments hazel (IV, 12). Chelte olive-yelhw
(VI, 16), mottled with olive-green. Finger tips oranrje (VI, 3), followed proximally
by a citron-yellow (VI, 15) band. One rufous articular tubercle above on the baud.
Articular membranes of hand lake-red (Vll, 2). Finger tips of chelte of second and
tbird pereiopods, and dactylopodites of fourth and fifth pcreiopods orange. Pereio-
pods pale brownish-white, mottled and niarlded with olive-yt'llow. Antennal Hag-
elluni annulated oli re-green and nvhracrous (V, 7). Spines on sides of carapace and
rostrum buff (V, 13). Antennal scale olive-i/ellow, its center olive-green.

It is to be remarked that in this specimen no dark olive-green band is found
near the finger-tips. The same was the case generally in specimens from Temple
Creek, Albion, and from Elk Creek (all collected in autumn). However, specimens
from Conneautville Station, Crawford County, collected in June, generally bad a
dark green, almost black band, succeeding the pale band. A similar dark Ijand
ajjpeared in some of the Temple Creek specimens, after they had been preserved
for some time in alcohol, but it disappeared again with tbe progress of the bleach-
ing action of the preserving fluid. In collecting the specimens of this species and
of C. obscurus in Erie County in October, 1904, I was generally able to distinguish
the two species, where they were found associated, by the color of the finger tips.
However, too much reliance should not be placed upon this character, since I was
not subsequently able to test this observation.

The description of this species, as given above, is drawn from si.\tv-one speci-
mens preserved in the collection of tbe Carnegie Museum. Of these, fifty-three are
from the State of Pennsylvania (forty-eight from streams flowing into Lake Erie,
five from tbe lake itself). One specimen is from Lake Erie, Erie County, Ohio, and
seven are from the northern parts of ^Michigan.

DISTRIBUTION (see Plate XLll, Fig. 3).
LOCALITIES REPRESENTED IX THE CARNEGIE MUSEUM.

Pennsylvania: Erie Couufg, Lake Erie, Presque Isle, (1). A. Atkinson coll.);
Lake Erie, Miles Grove ; Walnut Creek, Swanville ; Elk ( 'reek, Girard ; Elk Creek,
Miles Grove; ('onneaut Creek, Albion; Temple Creek, Albion; (^'rairfanl Cuuntg.
tributary of Conneaut Creek, Conneautville Station.

Ohio : Erie (_'(/unlij, Lake Eiie, Cedar Point, near Sandusky, (O. E. Jennings
coll.).

Michigan: Enrmd (hvniji, Crooked Lake, Oden near Petoskey, (E. B. William-
son coll.).

OKTMANX: THK CKAWFISHES OF THE STATE OF PENNSyrA'ANIA 363

PREVIOUS RECORDS.'

Type locality: Oswego, Oswego County, New York, (Girard)."

Caxada : Montreal, Quebec, (Faxon); Toronto, Ontario, (Faxon).

New York : St. Lawrence Count;], Grass River, (Hagen); Canton, (Faxon); Black
Lake, (Faxon); Ogdensburg, (Faxon); Jefferson Coiinfy, Garrison Creek, Sackett's
Harbor, (Girard); Oneida County, Oneida Lake, (Hagen); Caijuga Coantij, Cayuga
Lake, (Faxon); Monroe County, Rochester, (Hagen); Niagara County, Niagara-
(Hagen); Chautauqua County, Forestville, (Faxon).

Ohio: Lorain County, Lake Erie, (Ortmann); Ottawa County, Portage River, Oak
Harbor, (Faxon).

Michigan : Wayne County, Detroit River, (Faxon); North ville, (Faxon); Elcorse,
(Faxon); Washtenaw County, Ann Arbor, (Faxon); St. Clair County, St. Clair River,
(Fa.xon); Calhoun County, j\Iai-shall, (Faxon); Allegan County, Otsego, (Faxon); Sagi-
ninv Cmuity, Saginaw River, (Faxon); Charleimx County, Lake Michigan, Round and
Pine Lakes, Charlevoix, (Ward).''

Indiana : I)e Kalh County, Waterloo, (Hay); A'ohle County, Rome City, (Bundy);
Kosciusco County, TwrX^ay Lake, (Hay); Marshall County, !Maxinkuchee Lake, (Hay);
Twill Lakes, (Hay); Laporte Comity, Michigan City, (Faxon); Carroll County, Delplii.
(Hagen); Tippecanoe County, Lafayette, (Faxon); Marion County, Indianapolis
(Faxon); Irvington (Ha\'); Millersville (Hay); Franklin County, Brookville (Hay);
Brown County, Salt Creek (Hay); Monroe County, Clear Creek, Blooniington
(Faxon); Greene County, Switz City (Faxon); Sullimn Couiity, Turinan ("reek
(Faxon).'-

Illinois : Macon County, Decatur (Faxon); McLean County, Normal (Forbes);
Tazewell County, Pekin (Forbes); Kane County, Geneva (Faxon); Ogle County,
(Hagen); Stephenson County, Fi-eeport (Forbes)."

Wisconsin : Greene County (Faxon); Dane County, jNIadison (Faxon).

Iowa: Scott County, Davenport (Faxon); Wapello County, Ottumwa (Faxon).

New locality, not represented in ("arnogie Museum: Sponccrport. Monroe Co.,

New York, (Mus. Oberlin).

'I liave omitted '"Lake Superior" (Ha<;eii), as uiicoiilirmed (see Ortmami, IdO'^h, p. l:?21, ami "Gri-rn Kiver,
Ediuouson Couuty, Ivy." { Hay, ISOin, p. 235), as doubttul, beiiiK founded upon yoiinj; specimens only.

'"This is the first locality niven by Girard, and consequently is the type locality.

" Faxon ;;ive.s also from "Michinan": ".St. Mary's Ijjke " ; " Mouth of Battle Creek"; and "Lake Doujthias."
I hove not been able to locate these.

"Faxon gives in addition : " White Kiver, Indiana " ( soutlica,stern section, tributary to Ohio.)

"Faxon gives also : " Aux Plains Ui\cr, Illinois," which I have not been able t« locote.

364 MEMOIRS OF THE CARNEGIE MUSEUM

REMARKS.

Camharus propiiiquus in Pennsylvania belongs to Lake Erie and its drainage.
The range being rather restricted, the material at hand is not very rich, and its
study does not promise many results as to variation. Nevertheless there are a few
striking facts, which may be mentioned. In the first place one of the cliief specific
characters, the longitudinal keel of the rostrum, is decidedly variable. All speci-
mens at hand from outside of the state (pight) show a keel plainly, l)ut this is not
so with the Pennsylvanian specimens. The keel in these is often distinct, Imt shows
a tendency to disappear. This is chiefly the case in young individuals, where tlie
rostrum is comparatively narrower, the marginal spines are sharper, and the acumen
is slenderer than in older individuals.

The armatu]-e of the chelipeds is also rather variable. There is always a strong
spine in the middle of the inner margin of the carpopodite, and invariably a small
tubercle anterior to it, which in young specimens is often spiniforra. Sometimes
there is also a small tubercle at the proximal end of the inner margin, but I have
generally found this only in larger individuals. The lower side of the carpopodite,
as a rule, has only one spine, located at the articulation with the hand, and this is
present in all Tennsylvanian specimens I have seen. The anterior margin is often
without any spine, or even tubercle ; there is, however, a low tubercle developed in
many cases, and in two cases it was spiniform, viz., in a male (second form) from
Elk Creek, Miles Grove, and in a female from Presque Isle. Both of them had a
distinct keel on the rostrum, so that they undoubtedly belong to this species. The
rows of spines on the lower margin of the meropodite are generally represented by
only two spines, the distal spine of each row being alone present. Put it is remark-
able that in the set from ('onneautville Station, composed of twelve individuals, ten
show an increase of the spines of the inner margin, from four to eight little teeth
being present behind the large distal spine, while in eight specimens an additional
smaller spine is found behind the distal spine of the outer margin. In every case
this occurs only on one side, while the other side is normal. A similar increa.se of
the number of spines of the meropodite is also to be observed in a few specimens
from Temple Creek, Albion, in the two specimens at hand from IClk Creek, Miles
Grove, in the female from Presque Isle, mentioned above, and in the specimen
(female) from Sandusky, Ohio. Since the latter has also a s[)ine on the anterior
margin of the lower side of the carpopodite, the tendency to develop additional
spines may extend simultaneously to carpopodite and meropodite.

The set of seven specimens from northern IMichigan is remarkable for the fact

ORTMANN: THE CUAWFISHES OF THE STATE OF PENNSYLVANIA 365

that in no case is there a spine on the carpopodite at the lower articuhition with the
hand, but only a tubercle ; in other respects they are typical, with a spine and
anterior tubercle on the inner margin of the carpopodite, a low tubercle at the
anterior margin of tlie lower side of the carpopodite, and oidy two spines on the
lower margin of the meropodite.

Ill tlie shape of the sexual organs of the male there is much uniformity in their
length and llic shape of the tips. However, there is a tendency in the Pennsyl-
vanian specimens toward the development of a slight notch on the anterior margin
in the place where C. obscwus has a shoulder. I have only twelve males of the first
fcjrm from Temple Creek, Albion, four from Walnut Creek, and two from Elk
Creek. Of these, six from Temple Creek and one from Walnut Creek show a notch,
while all the rest (eleven) have no trace of it. The notch never assumes the shape
of the "shoulder" of C. obscunis, and the sexual organs differ in other respects
from the later species, chiefly in that the tip of the inner part is never blunt or
dilated.

The female annulus is rather constant, as has been said above; only slight differ-
ences due to age are noticeable.

We may sum up the variations of C. j)ropinquus in the state of Pennsylvania by
saying that there is a distinct inclination toward C. obsmrui^, indicated by the tend-
ency of the rostral keel to disappear, of the chelipeds to increase in spinosit}', and of
the male copulatory organs to develop a notch at the anterior margin. Nevertheless
there are numerous specimens which represent the typical C. propinqiius. This fact
is to l>e borne in mind, and we .shall learn more abovit it when we come to discuss
the geographical distribution of this and the related forms.

1 introduce here the systematic account of a variety of this species, which is
extralimital to the state of Pennsylvania. I have, however, decided to treat of it
more fully, since its relation to the representative Penn.sylvania form is highly inter-
esting, and since we shall have to refer to it repeatedly in the chapter on distrii)Ution.

2a. Cambarus (Faxonius) propinquus sanborni (Faxon).

Cnmbanis sanbomi Faxon, 1884i, p. 128.

CnmbnruH propinquus sn/ihorni Fa.xoii, ]885«, p. 91, Pi. .5, f. 3, PI. 9, f. 10 ; Underwood, 188(i, p. 372 ; Oshnrn iS: William-
son, 1898, p. 21 ; Williamson, 1899, p. 20, 18 ; Hay, 1899, p. 9G0, 961 ; Ortmann, 190.Vj, p. 132.

According to Faxon, this variety differs from the typical ('. propiiKimi.t in the
following characters: 1) The two parts of the male sexual organs are less deeph'
separated, and the tij)s are closer together. 2) The rostrum is not oarinate. 3) The
hands are finely pubescent. 4) The inferior median anterior spine of the carpopodite
is evident.

366 MEMOIRS OF THE CARNEGIE MUSEUM

I possess five specimens (obtained b_y excliange from (Jberlin Ojllege) from (ine
of the two localities oi'iginall_y mentioned by Faxon for this form (Oljerlin, (Jhio),
which agree well with his account, with tlie exception that the pubescence of the
hands is not developed; there are, indeed, a number of short hairs in some, chiefly
the younger, specimens, implanted in the pinictures, l)ut such are also very fre-
quently present in (J. prupinqaus (as well as in C. obncuras). These hairs are gener-
ally present in ncAV, recently moulted specimens, but wear off with age.

The male copulatory organs are very similar in shape to Faxon's figure, although
they vary slightly with reference to the length of the separated tips. In this
respect, however, the variety is closer to the typical form tlian to ('. ohscurua. In
addition, I notice in the two males of the first form of this set that the inner part of
the male organs, although it tapers to a point on a side view, is different on a poste-
rior view. From behind it is]^broadly and bluntly rounded off, a fact which is due
to a marked compi'ession and flattening in an anteroposterior direction toward the
tip. This is also the case in the male of the second form at hand. Here both tips
of the sexual organs are blunt, that of the inner part less so than that of the outer.
I cannot see that the tips of the male organs, either in the first or in the second form,
are closer together than in C. propi)iquus.

The armature of the chelipeds in these specimens is slightly different from that
of the typical (J. j>rojnnqiit(s, although similar variations have been observed in the
latter. In all five specimens there are two distinct spines on the lower side of the
carpopodite, one at the articulation with the hand, the other on the anterior margin.
The inner margin of the carpopodite, besides the one strong spine, has a distal and
a proximal tubercle, and in the two largest individuals (male and female) there are
a few additional tubercles on the upper surface (jf the carpopodite. The inner Icjwer
margin of the meropodite invariably has in these specimens behind the distal
spine a row of small teeth, becoming spiniform in the larger individuals. The num-
ber of teeth in this row is from six to eight. In two specimens the outer lower margin
possesses a small tubercle behind the distal spine of each cheliped. In one specimen
there is only a tubercle on the right side, and two others have only the distal spine.

In addition to the above specimens from Oberlin I have seen among the Oberlin
collections other specimens fi'om the state of Ohio, and have myself collected in
eastern Ohio and northern West Virginia a number of specimens, which undoubt-
edly belong to the same form. The characters are practically the same, and only a
few remarks ai'e necessary.

1. The keel of the rostrum is invariably lacking. There is not a single indi-
vidual which shows any trace of it.

OKTMANN: THE CKAWFISHES OF THE STATE OF PENNSYLVANIA 367

2. The hand of the achilt male of the first form lias a distinct tendency to
become broader than in tlie typical projnnquu.s. This is well shown in the largest
male from Oberlin. However, this may be due to the fact that the specimens of
this variety at hand are lari^er than those of the typical form. I notice, however,
in specimens from the Tuscarawas drainage and from West Virginia, a tendency in
old specimens, chiefly males, to develop on the upper surface of the hand, near the
double row of tubercles of the inner margin, additional low tubercles. The.se may
be scattered over the inner half of the surface, or a few of them (3-5) may form an
indistinct row between the upper articular tubercle with the carpopodite and the
articular tubercle with the dactylopodite. This is a distinct approach toward < '.
obscarus, where similar tubercles are present in larger individuals.

3. The two spines of the lower side of the carpopodite are almost alwa^'s well
developed. There are a number of specimens where they are only bluntly spiniform,
or even tubercular, but this is apparently due to wear, a large number of the speci-
mens at hand having been collected in spring, and pos.sessing old worn sliells, which
had gone through the winter. In a few cases the tubercle on the anterior margin
is barely indicated, but all these are cases of regenerated chelae, as indicated by
their size. The armature of the inner margin of the carpopodite entirely corre-
sponds to the Oberlin specimens, old specimens developing additional tubercles on
the upper side. A large female from Middle Island Creek, AA'. \'a., has on the left
carpopodite a small, l)ut sharp, accessory spine behind the large median spine.

4. Tlie armature of the meropodite is similar to the Oberlin specimens. There
is always a series of small teeth behind the anterior spine of the inner lower margin
(in old shells they may be indistinct, due to wear) ; the outer lower margin has an
anterior spine, and often a tuljercle or a small spine behind it. The latter is very
frequent in specimens from the Tuscarawas basin, while in those from the tributaries
of the Ohio in West Virginia it is rare ; nevertheless, in the large female from ^lid-
dle Island Creek this second spine is very prominent on the left meropodite.

5. The male copulator}' organs are of the j^ropinrfius-iype, that is to say, without
a shoulder. There is, however, a distinct tendency, not noticed in the Oberlin
specimens, to develop at the anterior margin a small notch in the male of the tii-st
form, and it seems that this tendency increases in specimens taken toward the
south. Out of ten males of the first form collected at Canton, Ohio, five have no
trace of this notch, two have a slight curve in its place, and three show it clearly.
This notch in these cases never assumes the shape of a "shoulder." In specimens
from Conotton Creek in Harrison and Carrol! Counties, Ohio, (only a few males of
the first form are at hand), no notch was observed. But out of thirteen males of

868 iMRMOlKS OF THE CARNEGIE MUSEUM

the fii'st form collec-ted in Fishing CJreek, West Virginia, only two liad no trace of
it; six had a curve developed in its place, and in five others it was distinct, in one
or two representing a blunt angle. The length of the tips of this organ vai'ies
sliglitly, but it is generally less than in C. uhscinKs. The tip of the inner part
always corresponds to that of the Oberlin specimens, Iteing compressed and rounded
off.

6. The annulus of the female is always of the propiiiqnus-typL', that is to say,
flat, with no tubercles. In old females it liecomes a little uneven, the anterior and
posterioi- parts being slightly swollen, but tliere are never two distinct tuljercles as
is the case in ('. ohscii.rns.

We may condense the varietal characters of this form as follows:

C. projiiv(ji(iis sanhanii clearly is nearer to proplnqmts than to C. ohscurufi on
account of tlie lack of a distinct shonldei' on the anterior margin of the copulatory
organs of the male of the tirst form, on account of the general shape and size of this
organ, and further, on account of the flat female anm/lus. It diftei's from ('. pro-
pincpms in the flattened and rounded tiji of the irnier part of the male oi-gan, in the
lack of a median keel on the rostrum, and in the shaj)e and ai'mature of the cheli-
peds, although the latter diflerences are slight and not always reliable. Just in the
latter characters, and in the tendency to develop a notch on the anterior margin of
the male organ, it inclines toward ('. obscurus. Thus it is clearly a transitional
form toward ('. uhsciirus of western Pennsylvania, and its geographical distribution,
as we shall see below, is also intermediate between ('. prcqnnquus and ('. ohscurus.

The colors of C. sanhonu agree throughout with those of (*. propiuquus and
(J. obscurus. The color of the newly laid eggs is dark olive-green, sometimes almost
black.

There are one hundred and sixteen specimens of this variety at hand ; Ave are
from the Lake Erie drainage in noi'thern Ohio ; eiglity-one from the Tuscarawas
drainage in eastern Ohio, and thirty from Fishing and Middle Island Creeks in West
Virginia.

DISTRIBUTION.

(See Plate XLII, Fig. 3.)
LOCALITIES RErRESENTED IN THE CARNEGIE MUSEUM.

Ohio: Lorain Countii, Waterworks Reservoii', Oljerlin (R. L. Baird coll., exch.
Mus. Oberlin); Stark ('ok id;/, West Ih'anch of Nimishillen Creek, Canton; Carroll
CounJij, (Jonotton Creek, New Hagerstown ; Harrison, ('oiotfi/, (Jonotton Creek,
Bowerstown; Tascarairas Couiiti/, Deimison [V. Sterki coll.).

ORTMANN : THE CRAWFISHES OF THE STATE OF PENNSYLVANIA 369

West Virginia: Wetzel Countij, Fishing Creek, New Martinsville; I'leasards
Coxiniy, Middle Island Creek, St. Marys.

PREVIOUS RECORDS.

Type locality : Smoky Creek, (."arter Ccjunty, Kentucky (Faxon).

Ohio: Loraiv Con7ity (Faxon); Vermilion River; Beaver Creek; French Creek
(Ortmann) ; ]Va;/iie ComU;/, Killbuck Creek, Creston ((_)rtmann) ; Tuscarawas
County, Tuscarawas River, (Iiiadenln'itten (Ortmann); Knox County, Big Jelloway
Creek (Osburn and ^Mlliamson) ; Licking County (Williamson) ; Franklin County,
Alum Creek (Osburn and Williamson).

3. Cami'.arus (Faxonius) okscurus Hagen.
(Plate A, Fig. 1 and 2; Plate XXXIX. Fig. 7a-7f ; Plate XL. Fig. 1.)

Camhartis olmvrvs Hagen, 1870. p. (i9, PI. 1, f. "2-"5. I'l. H, f. 154 ; Smith, 1874, p. 6:i9 ; Faxon, li^f^l//. p. 148 ; Fa.xon,

1898. p. 6.52 ; Ortmann, lOOon. p. 402.
Cambarus prupinquiiH olmvrvs Faxon, ISK'j", p. 92; Faxon, 'FS.")/). p. 'Mii\ : I'n(li-iv» I. It-t-fi p :{72 : llav 1>^!'n. |i.

960 964.
CnmbaruK priijihujuux and C. n/.s/id/.s Williamson, 19(il. p. Ki.
Vamharuii {Fuxoniua) oi.icui-i(.s- Ortmann, 190.54. p. 112.

Body of the same shape as in ('. ijropinepius, but .-^lightly more robust in old
specimens.

Carapace similar to C. propinquus, but tlie width of the hepatic, as also of the
branchial regions, is slightly gi'eater ; G : H : II = 1 : i.l : 1.3 to 1.5. These diHer-
ences of dimension may, however, be due to the fact that large individuals of this
species are at hand.

Cervical yroore and areola identical with those of C. projiiiiijuiis, but the areola
generally is sliglitly longer than half of the anterior section of the carapace.

Rostrum similar to that of C jiropinquus, but always without i.ny trace of a
median keel. In ycning specimens the rostrum and its acumen are about identical
in shape with those of C. propinquus. In nlder specimens there is a tendency to a
shortening of the acumen, which often reaches only to the distal end of the second
joint of the peduncle of the antennula and to tlie ba.se of the terminal joint of the
peduncle of the antenna. The marginal .spines in old individuals are often very
small and indistinct, represented by mere angles. The postorbital ridges are as in
C. pro]>iuijuus.

The punctures and spines of the carapace are identical with tiiose of C
propinquwi.

:)70 MEMOIRS OF THE CARNEGIE MUSEUM

The (iliddmcn, epidoma, anfcniiiild, and (iiitciiiid ai'o also similar to those of ('.
[)ropinquut<.

The fi.rd pcrciopods (Plate XL, Fig. 1) are generally more robust than in ('. pro-
'pinquus, particularly in adult males. Hand wider and more distinctly depressed.
The fingers more widely gaping in old males, and the S-shaped curve of the movable
finger more pronounced ; in old females there is also a slight gap at the base of the
fingers. The upper surface of the hand possesses, particularly in large specimens,
a small number of scattered low tubercles near the inner margin, and very often
(but not always) there is a row of 3-5 tubercles running toward the base of the
movable finger, parallel to the inner margin. Tubercles of the outer margin of the
dactylopodite more jtrunounced. The sculpture of the hand is rather variable, and
must distinctly developed in t)ld males. The shape of the hand is ratlier different
in the male and female ; in the female the fingers are shorter, less gaping (or not at
all), rendering the outline of the hand more regularly ovate. (See Plate A, Figs.
1 and 2.)

The carpojHjilite differs from that of C. prophiqmis in the development of a
strong tubercle on the anterior margin of the lower side. This tubercle very rarely
is indistinct (chiefly so in regenerated claws) ; generally it ends in a distinct, stout,
conical spine. On the inner margin and on the upper face additional low tubercles
are not infre<juently found.

The meropodite differs from that of ('. projiliKfuus by the constant presence of a
series of 4-8 small tubercles, or teeth, behind the distal spine on the imier lower
margin. These teeth are never wanting in any of my specimens. The outer lower
margin has one or two spines. The latter number is comparatively rare. In re-
genei-ated claws very often there is no spine at all on the inner lower margin.

The other characters of the pereiopods are similar to those of C. pruptitqaus.

The p'rst pleopnd.^ of male of the first form (Plate XXXIX, Figs, la and Ih) are
of the general type of those of T. jirapi ikjuus, but slightly longer, reaching to the
anterior margin of the co\o})odites of the third pereiopods. The inner part does
not gra<lually taper to the tip, but is of neai'ly uniform thickness, with the tip
rounded off and slighth' compressed in tlie antei'o-posterior direction. Sometimes
tile tip is even slightly thickened. The anterior margin of this organ, at a point
somewhat below the separation of the two parts, has a rather sharp, well marked
shoulder, which is absent in none of the specimens at hand (several hundred).

In the male of the second form (Plate XXXIX, Fig. 7c) this shoulder is missing,
and the inner part is blunt, similar in shape to the male of the first form, and not
tapering to a point as in the typical ('. pnqjlnqaus.

OKTMANN: the CRAWFISHES OF THE STATE OF PENNSYLVANIA 371

The avnidus ventndi.s of the female has the general shape of that of (.'. proj)in-
quas, but the depression in the middle is well marked, and the anterior part has
two distinct, subconical tubercles. The posterior part is also elevated into a flat
and low tubercle. These tubercles are less distinct in young specimens, but always
well developed in females of medium and large size.

Size. — Hagen gives the length as 3.5 in. = 89 mm. The largest individual at
hand is a female from Pucketta Creek, Allegheny County (Atkinson coll.), wliich
measures 93 mm. in length. Tlie largest male of the first form is from the Ohio
River at Neville Island, Allegheny Co., which is 8G mm. in length. Individuals
over 80 mm. in length are not rare in the larger rivers.

Colori) (Plate A, Figs. 1 and 2). — The colors of this species are identical with those
of C. prfqnnqtms. In fresh specimens the general ground color is light olive-green
(Ridgway, 1886, X, 18), with darker spots in young specimens ; in older individuals
it is rather taivny-olive (III. 17). On the branchial region there is an oblique band of
cream-color (\l, 20), edged by olive-green near the margin of the carapace, which is
again cream-color. This cream-color in very brightly colored specimens sometimes
becomes primrose-yellow (VI, 13). On the anterior margin of the carapace below the
eyes there is a spot which may be rufous (II, 7), ocliraceous-rufous (V, 5), edged with
sulphur-ijelloxv (VI, 14), ochre-yellow (V, 9), or primrose-yellow (VI, 13). The abdomen
is olive-green or lawny-olive, shading into chestnut (IV, 9) on the anterior margins of
the segments. There are one (sometimes two) median and two lateral rows of dark
olive-green patches. The chelte are light olive-green, shading distally into olive-yellow
(VI, 16). The finger-tips are orange-buf (\'I, 22), orange [Xl, 3), or raw sienna
(V, 2), followed by a pale, and a dark green, sometimes almost black band. Tlie
latter is not alwaj's present. The upper surface of the hand at tlie base of the dac-
tylopodito has two (rarely one) rufous or ochraceous-rufoas (V, 5) articular tubercles.
The tubercles of the hand are huff-yellow (VI, 19) or huff (V, 13). The articular
membranes of the hand are wine-purple (VIII, 15). The legs are olirr-yellow (VI,
16) and whitish, with olive-green on upper edges.

The above colors fade in old specimens, and are often obscuivtl l)y blackish or
brownish coats oi'dirt. .\ variety with the chehe and anterior parts of the carapace
of a pale dirty liluish color was repeatedly observed in tlie Alleghany River at
Sandy Creek and Twelve Mile Island, liut only old specimens of this form were
found. Young specimens generally vary more toward green, old ones toward tawny
or brown.

The color of the newly laid eggs ranges from sage-green (X, 15) to dark olive-
green (X, 18), or often to almost bku:k. When somewhat advanced in development,

372 MEMOIRS OF THE CARNEGIE MUSEUM

the egg becomes in jiart prunc-piirple (VIII, 1), in part c ream-color (VI, 2(1), or
whitish.

Of this species, seven hundred and twenty-one specimens are at hand. Most of
them (six hundred and sixty-two) are from the state of Pennsylvania ; tifty-seven
are from the "Panhandle" of West Virginia, and two Irom Maryland (Wills
Creek, Ellerslie). Many others have been collected, but no record has been kept,
since they were used for exchange, dissection, and exjieriment.

DISTRIBUTION.

(See Plate XLII, Figs. 2 and 3.)

LOCALITIES REPRESENTED IN THE COLLECTIONS OF THE CARNEGIE MUSEUM.

Pennsylvania: C recur (buiifi/, Pennsylvania Fork of Fish ('reek. Deep
Valley; Smith Creek, Waynesburg ; Bates Fork, Deer Lick; Pumpkin Run, Rice's
Landing; Fayette Count j), Cheat River, Cheat Haven; Youghioglieny River, Con-
nelsville ; Washiinjtdu Cimniij, Buffalo Creek, Taylorstown ; Harmon's Creek, Dins-
more; Raccoon Creek, Burgettstown ; Pigeon ('reek and Taylor's Run, Mononge-
hela (-'ity ; Beaver County, Beaver (S. N. Rlmads coll.); Raccoon C_'reek (Atkinson,
Williamson and Todd coll.); Little Beaver Creek, New Galilee (A. Koenig coll.);
Brady's Run, Fallston ; (Jhio River, Baden; ( )hio River, Andjridge ; Jjnrrciice
County, Eckles Run, Wampum ; Big Run, Newcastle (D. C. Hughes coll.); Mercer
County, Otter Creek, Mercer; Shenango ('reek, Hadley ((). E. Jennings coll.);
(Jrairford County, Shenango River, Linesville ; Shermansville ((J. E. Jennings coll.);
Conneaut (Jutlet (D. C. Hughes coll.); ( )il Creek, Spartansburg ; Erie County,
( 'onneaut Creek, Albion; Elk Ci-eek, ]\Iiles Grove; French Creek, Union City;
Jlatlcr County, Ti'ibutary of Slippeiy Rork ('reek, Branciiton ; Thorn ('reek, Ren-
frew; Rough Run, West Winfield ; Allcyhrni/ t'ounty, ()]iii) River, Neville Island;
( )hio River, Bellevue (E. Hays and R. Taylor coll.); < )hio River, Shoustown ;
Flauglierty Run, IMoon Township ((^). T. Shafer coll.); ( 'hartiei's ('reek, (Jarnegie
(D. A. Atkinson coll.); (^'hartiers (Jreek, Bridgeville (D. A. Atkin.son coll.); Turtle
Creek, Pitcairn (D. A. Atkinson coll.); Youghiogheny River, Boston (D. A. Atkinson
coll.); Cry.stal Lake, Pittsburgh (D. A. Atkinson coll.); Girty's Run, ]Millvale; Stone
Run, Thornhill ; Pine Creek, below Bakerstown Station (D. A. Atkinson coll.);
Alleghany River, Six jMile Island, (S. N. Rhoads and E. B. Williamson coll.);
Scjuaw Run, Aspinwall ; Alleghany River, Sandy (^'reek ; Alleghany River, Verona
(D. A. Atkinson coll.); Alleghany River, Twelve Mile Island ; Deer Creek, Harmar-
villc ; Little Deer ( 'reck, Russelton ; Pucketta (Jreek (D. A. Atkinson coll.); Little

ORTMANN: THE JRA.WFISHES OF THE STATE OF PENNSYLVANIA 373

J)ull Creek, Tarontuni (A. Kcunig coll. ); Alleghany River, Butler Junction; lIV.s^-
moreland Countij, Kiskiniinetas River, Livermore ; Conemaugh River, Blairsville
Intersection; Reservoir of McGee Run, Derrv ; Whitethorn Creek, Dundale; small
tributary of Loyalhanna River, New Alexandria; Loyalhanna River, Ligonier ;
Loyalhaiina River, Crisp; Indiana Countij, Two Lick ami Yellow Creeks, Homer;
Crooked Creek, Creekside ; Little Mahoning Creek, Good ville ; Armstrong Count;/,
Long Run, Avonmore Station; Alleghany River, Kittanning; Alleghany River
and Pine Creek, iNIosgrove ; Alleghany River, Templeton ; Clarion Count jj, Alle-
ghany River, Red Bank ; Jefferson Couvty, Pond at Punxsutawney ; Clearfield
County, Sandy Lick Creek, Du Bois ; Venango County, Alleghany River, Franklin ;
Oil Creek, Oil City ; Forest County, Alleghany River, Tionesta ; Warren County,
Brokenstraw Creek and Crouse Run, Garland ; McKean County, Alleghan}^ River,
Larabee ; Bedford County, Wills Creek, Hyndman.

West Virginia: Hancock County, Llarmon's Creek, Holidays Cove; Brooke
County, Harmon's Creek, Colliers ; Ohio County, Wheeling Oeek, Elm (irove ; Mar-
shall County, Wheeling Creek, Union Township; Grave Creek, Cameron;
Pennsylvania Fork of Fish Creek, Xuss ; Wetzel County, Fishing Creek, New
Martinsville.

Maryland : Alleghany County, W' ills Creek, Ellerslie.

PREVIOUS RECORDS.
Type locality : New York, Monroe County, Genessee River, Rochester (Hagen),
New York : Cattaraugus County, Alleghany River, Salamanca (Ortmann).
Pennsylvania : Westmoreland County (Faxon); Allegheny County (M'illianison);
Warren County, Alleghany River, Corydon (Ortmann).

ADDITIONAL LOCALITIES.

Material in the Ikpartrncnt of Agriculture, Harrishurg, collected by 11'. Jl. McCon-
nell. — Shenango River, Jamestown, ^Mercer County; French Creek, Franklin,
Venango County ; small stream and pond, below Indiana, Indiana County ; Branch
of Genessee River, Ulysses, Potter County.

Alleghany River, ^lontrose, Allegheny County, Pa. (collected by the writer, but
material used for study); Indian Creek, Jones Mills, Westmoreland County, Pa.,
(seen by the writer);" Hai-mon's Creek, Hanlan, Washington County, Pa. (seen by
tlie writer); Ohio River, Congo, Hancock County, W. \'a., (seen by the writer).

'*Tliis locality was discovered in the l>cf;iniiiii{; of tlic iiivestiK-itioii by the writer, niul siuce its imporlnncc «n»
then not understood, no specimens were preserved ; but the record is absolutely trustworthy.

374 MEMOIRS OF THE CARNEGIE MO.SEUM

REMARKS.

CariiJianis (;/*.sTv/rv/.v is tlie river species of tlie Upper ()hit) drainage. It is widely
distributed in western Pennsvlvania. Compared with the allied species C. propin-
quus. which occupies a much wider area, it is ratlier uniform in its characters all
over its known range. It nowhere reveals a tendency to vary in the direction of
('. propiiKinn^i, or of propliKjuns sanhonii. This is the more remarkaljle because C.
prnpuKpxus distinctly inclines toward this species in Erie and Crawford ( 'ounties, (in
the lake drainage), and likewise because C pnijiiiujnin^ Hunhomi shows such a ten-
dency in Wetzel (bounty, A¥est Virginia.

The variations observed in our abundant material have been briefly indicated
above. However, it deserves special mention that the specitic charactei's are
scarcely subject to any variation.

Very interesting conditions are offered liy the spines of the outer lower margin
of the meropodite of the cheliped. One or two spines ma_y be present, the prox-
imal one smaller and often represented only by a small tubercle. Looking over our
material, I find that only one spine is present in all individuals from the upper
Alleghany drainage, including all the tributaries from Red liank ( 'reek northward
(sixty-one specimens are at hand). In Armstrong, Indiana, Westmoreland, and
Allegheny Counties, in the drainage of the Alleghany River, and in the whole
drainage of the INIonongahela, the Beaver, and ( Jhio proper, a second spine may be
present, but such cases are not frec|uent, and generally this spine is f(_)und only on
one of the two chelipeds. There is a tendency of this character, more frequentlj'
dis})layed in the southwestern extremity of the range. Two such .spines on either
side (right and left) are very rare, and I have found them only in twenty speci-
mens; fifteen of which Ijelong to the ( )hio drainage: two to that of the Monongahela,
six to that of the Beaver, and seven to that of the Ohio below Beaver. Two cases
were discovered in Wills Creek, ^Maryland, and three in Conneaut Creek at All)ion,
Erie County, Pa.

The latter specimens are interesting inasmuch as in Erie and Crawford Counties
two drainage areas come together with that of Lake P]rie, namely, that of the
Shenango River, a tril)utary of the Beaver, and that of French Creek, a tributary
of the Alleghany. In the latter ci'eek and its trilmtaries I have never seen
an individual with two spines (seventeen specimens arc at hand). Among the
material from the Beaver River di-ainage (fifty-six specimens) there are twenty-
one with two spines. Thus the tendency to develop two spines is markedly present
in the drainage of the Beaver, while it is apparently absent in Fi'ench Creek.

ORTMANN : THE CRAWFISHES OF THE STATE OF PENNSYLVANIA 375

The specimens from the Lake Erie drainage in Conneaut Creek quite often liave
two spines (eight specimens out of twenty-two), and thus correspond to the Beaver
River form, and to those from Elk ( "reek, in which one specimen out of six lias two
spines. Tlius it appeare that tlie form in the drainage of Lake Erie more closely
approaches the form found in the Beaver River tlian that found in French ('reek,
although it must he granted that tlie material at hand seems to he not entireh'
satisfactory, being somewhat too scanty from French ("reek, and decidedly insuf-
ficient from Elk Creek.

A feAV freaks have come under observation in the following cases :

1. As has been said, the rostrum reveals in old individuals a tendencj' to a
shortening of the acumen. The extreme is reached in a specimen (male of the first
form) 74 mm. long, from Conneaut Outlet, Ci-awford County (D. C. Hughes coll.),
where the acumen is broadly triangular and hardly longer than the short marginal
spines, reaching onl}' to the distal end of the basal joint of the peduncle of the
antennula. The acumen is well formed (not deformed), showing no traces of injury.
But that this specimen undoubtedly has been injured at some time earlier in its life, is
revealed by the fact that both claws are comparatively' small, and by the characters
of regeneration (lack of spines on the outer lower margin of the meropodite, the
absence of a tubercle on the anterior margin of the loAver side of the carpopodite,
and the generally weak and slender shape).

2. A female (46 mm. long) from lirokenstraw Creek, (Jarland. Warivn ("ounty,
has the acumen of the rostrum directed obliquely to the left side, and the right
margin of the rostrum has five marginal spines. This seems to be due to an injury
received in earlier life. The left claw is also smaller and of the regenerated type.

3. A specimen (5.5 mm. long) from the Alleghany River at Sandy Creek (col-
lected by the writer, Nov. 19, 1904, Cat. No. 74. 479), has the characters of a female
in the shape of the chehe and the lack of hooks on the pereio|)ods. The annulus
ventralis, however, is very indistinct, although its outlines and slight median
depression are visible, as is also the median fissure. l>ut this inilividual has the
male genital opening in the coxopodite of the fifth pereiopod, and the first pleopod
is of the male type, although small ; it is unusually short, reaching only to the
anterior margin of the coxopodites of the fourth pereiopods ; it is of the type of the
first firm, wilii a distinct shouldci-; tiic outer part is horny and <listinctly longer
than the inner part. 'I'lic srcoml ])ieopods are entirely of the male type. Accord-
ing to the sexual orifice and the copulatory organs, we are to regaril this as a male
with certain female characters.

4. A pendant to the last specimen is i)ne (G7 mm. long) from the Ohio River,

376 MEMOIRS OF THE CARNEGIE MUSEUM

Neville Island, (collected by D. A. Atkinson, May 14, 1899, CVit. No. 74. 36). The
claws are intonnediate between male and female, but iiu-linini:,' toward the male
form. The third pereiopods have strong and well developed hooks on the ischio-
jjodites of the type of the first form male. The first pleopods are very peculiar,
(Plate XXXIX, I'igs. Id and 7t;), and unlike those of ('. oJisciinis : they rather
resemble those of C. li'inosiis. Their length and strength are normal, but there is no
shoulder, and the two parts are separated only for a short distance at the tips, similar
to C. Jiiiiosa-^, but the tips are not twisted. The outer tip is horn_y and pointed, the
innei- suft, thicker, and tapers to a blunt point. The second pleopods are of the
normal male type. In addition this individual possesses a well developed amiulus
ventralis, and sexual orifices only on the third pereiopods. Thus it appears to be a
female, with the secondary sexual characters of the male well, but not specifically,
developed.

None of the two cases of apparent hermaphroditism just descril>ed (Xos. 3 and 4 )
agrees with any of the four cases mentioned by Faxon, (1S85(( p. 13, 14), or the four
described by Hay, (1905, p. 226 and 227). Additional cases will be described below
under C. hartani. There is in tlie ( 'arnegie Museum a furtber individual of herma-
phroditic character, namely a specimen of Caniharn.i ruMicus Girard, from the
Wabash River, Bluffton, Indiana, collected by Mr. E. B. Williamson, June 1, 1905,
Cat. No. 74. 57cS. I a{)pend a description of it.

The specimen is externally a female, possessing the female type of claws, a well-
developed annulus, female sexual openings, and no hooks on the third pereiopods.
But the first pleopods are peculiar ; they are short and stout ; the bases are iden-
tical with those of the male pleopods; the distal parts, however, reach only to
about the middle of the coxopodites of the fourtb pereiopods; their tips are soft,
blunt, and slightly curved inward, and possess the furrow which divides them into
an outer and inner part, but tliese parts are not separated at the tips. The second
pleopods are of the female type. This case corresponds in a certain degree to the
second, third, and fourth, mentioned by Faxon, chiefi}' so to the third (in C. diog-
enes). The specimen is apparently a normal female, only the first pleopods are
transformed in a peculiar way, resembling the male type generallj% but differing
from the specific shape. In the present case the first pleopod is different from
Faxon's case in detail.

ORTMANN: THE CRAWFISHES OF THE STATE OF PENNSYLVANIA 377

4. Cambarus (Bartonius) bartoni (Fabricius).
.Plate B, Fiji. 1 ; IMate XXXIX, Fig. ]ctr-]f, and Fig. 8 ; Plate XL, Fig. 2.)

Astacus harloni Fabricius, 1798, p. 407 ; Say, 1817, p. 167 ; Harlan, 1835, p. 230. f. 3 ; Gould, 1841, p. 330 ; Thompson,

1842, p. 17(1 ; De Kay, 1844, p. 22, PI. 8, f. 23 ; Gibbes, 1850, p. 195, (jmrtim).
Aatacus ciliaris Kafinesque, 1817 p. 42.
Aalacus pusillus Rafinesque, 1817, p. 42.
Astacus ojjiuis Milne-Edwards, 1^37, p. 332 (non Say).
Cambdrus barluni Girard, 1852, p. 88; Bell, 1859, p. 210; Hagen, 1870, p 7.5, PI. 1, f. 47-50, PI. 2, f. 1:55-139. PI 3,

f. 166; Abbott, 1873, p. 80; Smitb, 1874, p. 639 ; Putnam, 1874, p. 191 ; Faxon, 18846, p. 22; Kaxon, 1885a, p.

59 ; Faxon, 18856, p. a58 ; Underwood, 18*'6, p. 367 ; Ganong, 1887, p. 74 ; Faxon, 1890, p. 622 ; Hay, 1896, p.

487, f. 6; Faxon, 1898, p. 649; Osburn and Williamson, 1898, p. 21 ; Williamson, 1899, p. 47; Hay, 1899, p.

959, 966 ; Williamson, 1901, p. 11 ; Ortmaun, 1905ri, p. 3!H) ; Paulmier, 1805, p. 134, f. 6 ; KathbuD, 1905, p. 18.
Camharus pimllus anA monlanus Girard, 1852, p. 88.
Cambarus {Jinrlonius) barloni OTtmUBD, 1905i, p. 120, 134.

Body robust, very sparsely pubescent in fresh, but perfectly naked in old speci-
mens, with only a few hair8 on the fingers of the cheltc, and sometimes a slight
pubescence on the cutting edge of the fingers.

Carapace subovate, strongly depressed. (V : 7/: /> = 1 : 1..') or 1.4:1.5 or 1.6.
Greatest width of branchial regions well forward, at a short distance behind the
cervical groove. Upper surface of carapace very Hat.

Cervical groove deep, not interrupted on the sides. Areola distinctly longer than
half of the anterior section of carapace; a:p = 1 :0.6 Areola rather broad («• : /
= 1 : 5 or G), with about 3-5 irregular rows of punctures.

Rostrum (Plate X.\ .\ I .\, Ilg. l'/-l/') broad and short, reaching generally to the
distal end of the second joint of the peduncle of the antennula, and hardly be-
yond the middle of the fourth joint of the peduncle of the antenna. Upper surface
almost flat or only slightly concave, but margins elevated, without marginal spines.
The margins converge more or less from the base, sometimes they are almost par-
allel, and near the apex they are suddenly contracted into a short, triangular acu-
men having a sharp point. The angles at the base of the acumen are rounded, but
generally well marked, and the elevated margins are continued to the apex, al-
though slightly decreasing distally from the lateral angles. Postorbital ridges short,
almost parallel, angulated anteriorly, but without spine, except in young
specimens.

Surface o/co?-«^:)rfcci punctate, distinctly granulated on the hepatic region in larger
specimens. There are also a few more or less distinct granulations immediately be-
hind the cervical groove, but no spine. External orbital angle well marked by an
angulation or a small tubercle, more rarely, and only in young specimens, spiniform.
Branchiostegal spine formed by a small tubercle, which is sometimes ol isolate.

378 MEMOIRS OF THE CAKNEGIE MUSEUM

Abdomen as long as carapace, or slightl}' shorter or longer ; it is slightly wider in
the female than in the male, but hardly wider than the carapace in the former.
Anterior section of telson on the posterior lateral corners generally with two, more
rarely with three spines. Posterior section senii-elliptical, distinctly wider than
long, slightly shorter than anterior section.

Episfoma with posterior part broad and short, about two and a half times as
broad as long, with a distinct transverse groove on either side slightly posterior to
the middle, and an anterior median depression. Anterior section consti'icted at
the base, semi-circular, with a median anterior point. This point may be strongly
developed, or almost entii'ely absent. Transverse diameter distinctly greater than
the longitudinal.

Antciiinila with a small, often spiniform, tubercle on the lower margin of the
basal joint.

Anfctinal pedunde with a tubercle on the outer side of the first joint, which is
often spiniform, chiefly so in young specimens ; second joint with or without a very
indistinct tubercle.

Anteniial scale short and narnjw, slightly longer than the rostrum, reaching to,
or almost to, the end of the fourth joint of the antenna! peduncle. Spine of outer
margin strong. Laminar part not much broader than the marginal spine.

FhtgeUum reaching to the anterior mai'gin or to the middle of the telson in the
male, slightly shorter in the female, but sometimes considerably shoi'ter, without
apparent trace of having been injured. In some cases it reaches only the middle of
the second abdomiiaal segment.

First pereiopods (V\i\te XL, Fig. 2) very strong and rolmst in old individuals,
particularly males. Hand elongate-ovate, broad, and strongly depressed. Surface
punctate. Inner margin of palm short, curved, with a single marginal row of moi-e
or less distinct, low tubercles. Outer margin smooth, rounded proximally, carinate
distally. Fingers longer than palm, not gaping in young individuals, but with a
wide gap at the base, meeting only at the tips, most noticeably in old males.
Outer margin of movable finger punctate, or, in older specimens, with a few indis-
tinct tubercles. Cutting edges with tul)ercles, larger in the proximal part. Upper
surface of each finger with a low longitudinal rib, boi'dered by rows of pvinctures.
This rib often becomes indistinct, especiall_y on the movable finger in old males.

Ciirpopodite slightly longer than wide, shorter tlian palm, with a deep longitud-
inal sulcus above. Inner margin with a strong pointed or Idunt spine, which is
generally distinctly hooked, going off almost at a right angle, l)ut curving foi'ward
in the distal part. A small spine or tubercle (sometimes double) may be added to

OUTMANN : THE CUAWKISHIiS OF THE STATE OF PENNSYLVANIA 379

it proxiinally. Ijower surface with a Ijlunt conical tul)ercle in the middle of the
anterior margin (occasionally spiniform). The tubercle at the articulation with the
hand is generally obsolete. There are sometimes additional tubercles ; the one
which most frequently occurs is a small spine or tubercle between the large one on
the inner margin and that on the anterior margin of the lower side.

Meropodite smooth, with 1-3 tubercles near the distal end of the upper margin,
one of which is often spiniform in young specimens; in old specimens they are
generally very indistinct or wanting. Lower .side witli two rows of spiniform
tubercles. Tlu' outer rows consist of 1-6 (very rarely <jnly (jne tubercle). Six were
found in only one instance, that of a regenerated cheliped. (Generally there are
two or three. The inner row has (j-11 spiniform tubercles, of which the distal is
the largest. A small tul)ercle on the outer articulation with the carpopodite may
be present or aljsent.

Ischiopodite of third pereiopod hooked in the male. The hook of the first form
is strong and subconical.

The coxopodite of the fourth pereiopod in the male possesses a prominent rounded
and compressed tubercle.

Fird pleo'pods of the male of the first form (Plate XXX IX. Fig. 8) stout and
short, reaching to the posterior margin of tlie coxopodite of the third pereiopods.
They are not articulated at the base. The two parts are separated at the tips for a
short distance, and both are curved sharpl}' backward, forming almost a right angle
with the basal part. Distally they are partly twisted, so that the outer part is
directly anterior to the innei-. The outer part is horny, compressed, falciform, the
tip pointed, with a small posterior accessor}' point (often worn off). The inner
part is soft, swollen at the base, and suddenly tapering to a blunt point.

In the male of the second form this organ may be articulated at the base (in the
case of the young) or not articulated (in older specimens). Both jnirts are separated
distally for a short distance, and the outer part is soft, not horny, le.-^ distinctly
compressed, and Muiit. In the young these organs are considerably shorter than in
older specimens.

Aimulus ventndis of the female transver.sely rhombiform, with a deep central
depression and a longitudinal S-shaped fissure. Anterior and more particularly the
posterior margins elevated. The whole anterior portion of the annulus often apj)eai-s
depressed compared with the elevated posterior margin, ^^'here the longitudinal
fissure passes over the posterior margin the latter is slightly depressed. In young
females the central depression is less marked, and tlie margins are consequently less
elevated, giving a rather fiat appearance on the annulus.

380 MEMOIRS OF THE CARNEGIE MUSEUM

Size. — This species in western Pennsylvania reaches a considerable size, although
the niaxinium recorded l)y Hagen (.'!.G = 91 mm.) has not been observed. Faxon,
(1885o, p. 64), mentions a specimen from the Mammoth Cave, Ky., measuring 108
mm., but this is not the typical form. The largest individuals in the Carnegie
Museum are two females, the one from Braeburn, the other from Derry, Westmore-
land County, both measuring 87 mm. in length. The largest male (first form) is
from North Versailles Township, Alleglieny County, and measures 83.5 mm.'' In
Avestern Pennsylvania specimens over 80 mm. ai'e not altogether rare.

In the eastern portions of the state this species is much smaller. The largest
specimen at hand is a female from Hoxboro, 07 mm. long, and a male (first form)
from Manayunk, Philadelphia ( Jounty, 66.5 mm. long, (both collected by H. Cera).
Specimens over GO mm. are not frequent in eastern Pennsylvania.

Colors. — Generally dull and not much varied, greener in 3^oung specimens,
browner in old ones. (See Plate B, Fig. 1.)

The carapace and abdomen olive-green (Ridgway, 1880, X, \8) to tawitij-otive
(III, 17), chfstniit (IV, 9), and hnnil umher (III, 8), a shade darker dorsally, lighter
on the sides. Margins of rostrum, in llie browner specimens, fcrragiiieous (IV, 10).
Distal third of finger rvfuns (IV, 7), or town)/ (V, 1 ). Tul>ercles of the cutting edges
of fingers ochnicco/i-^ Jinff' (V, 10). In brown iiidiviihuds there is generally some
green on the chelse.

Aside from young individuals, where the normal olive-green prevails, this species
shows a distinct tendency toward the brown and chestnut shades, more so than the
river .species, C. limosn.'t, (_'. propi iii[iin-'<, and '". oli.^c/Arm.

In some cases the colors are brighter. Individuals shading to a copper-color are
not rare, and I have seen a few where a dirty slate-ljlue was the ground-color. Of
coui'se, as in other species, in old si)ecinieus the original colors are largely obseui-ed
by a deposit of mud, rendering tiie specimens sometimes almost black.

In verv young specimens (10 to 20 mm. long) the col(.)r is olive-green, .semitrans-
parent, with the chehT3 almost entirely ferrugineous.

The color of the newly laid eggs is almost black, with, or without, a purplish hue
{ivdixuL-jntrplc, VIII, ('>). In a more advanced stage they become particolored;
prune-par pic {Will, l)or dahlin-parple {\ll\, 2) on one side, graijishov whiti'sh on
the other.

The Carnegie Museum possesses seven hundred and fifty-five specimens of this
species, six hundred and fourteen of which are from the state of Pennsylvania,

"The female from Hill, We.stmorelaud County, mentioned previously (Ortmann, 1905((, p. 391) is 85 mm., not
89 mm. as stated ; the male from Cheat lih-eT {ibid. ) is not 92 mm., but 82 mm. in length.

ORTMANN: THE CRAWFISHES OF THE STATE OF PENXSYLVANIA 381

ninotecn from New York, ten from New .Jersey, six from Oliio, seventy from West
Virginia, thirty-four from Maryland, and three h-om North Carohna.

DISTRIBUTION.

LocaHties represented in the collection of the Carneyie Museum.

Pexxsvi.vama : Delaware Couviy, Dicks Run, Wallingford ; PkUcuklphia Coiuiiij,
^lanayunk, (H. Gera coll.); Domino l.ane Run, Rqxboro, (II. GeracoU.); Wis.-;a-
hickon ; Bucks Cotoifij, Grenohle ; I'ark Hollow Run, New Hope; Xorthninpton
Coiinfi/, Bushkill Greek, Easton, (A. E. Davison coll.) ; Lthiijlt Coiniti/, Little Lehigh
Greek, Emaus ; iVoiifgomcrij Coviilij, West Manayunk, (H. Gera coll.) ; Buckn Count i/,
Shoeniakersville ; ('hosier Coviili/, \'alley Forge ; Lancaster Couiitif, Pequea ; York
Couiily, Ai'thur Run, York I'uinace ; Dauphin County, Susquehanna River, Halifax ;
Northumberland County, Geoi'getown ; Franklin County, Dickey ; Williamson ; /*'«/-
ton County, Dogtown ; Big Gove Greek, McGonnellsburg ; Blair County, Frankstown
Bnincli of .luninta River, Loop near 1 Iolliday.->hurg ; Bedford County, Bedford
Springs (A. Koenig coll.) ; Cameron County, Sinnamahoning Greek, Driftwood ; Sin-
namalioning ; Cambria County, Tributary of Clearfield ( 'reek, Ashville ; Headwaters
of Glearfield Greek, Gresson ; Sunniiit, (S. N. Rhoads coll.); Laurel Run, Lovett ;
Somerset County, Wills Greek, INhmce ; Flaugherty Greek and tributaries, Sandpatch ;
Gassehnan River, Rockwood ; Windber ; Laurel Hill, west of Jennerstown ; Indiana
Cuuidy, Cush-( 'usliion ( "leek, west of ('berry Tree; Homer; Creekside ; Goodville ;
Jefferson County, Mahoning Greek, runxsutawney ; Brock way ville ; Brookville ;
Clearfield Gir^n?<</y, Falls Greek; Elk County, Elk Creek, Ridgway ; l'olt<r t'nunty,
Keating Summit ; MrKcan County, Larabee; Warren County, Crousi: Bun, ( iarland ;
Forest County, Tionesta ; Venamjo County, Sage Run, Oil Gity ; Clarion (ounly,
Alleghan}^ River, lied liank ; Arvistrony County, Long Run, Avonmore Station;
Weskit, opposite Kittanning; Bine Creek, Mo.sgrove ; Alleghany River, Templeton ;
Wrslnioreland County. Tub Mill Bun, Ross Furnace, South of New Florence; Crisp
(11. 11. Smith and .M. .\, Wiitbiinicr coll.): Lynn's Knn. Mechanicsburg ; Loyal-
hanna River, Ligonier : Indian Creek, .b)nes Mills; Reservoir of .McGee Bun,
Derry ; Witlu'tlinni Creek, Dundale; Livermore; 1 1 ill. opposite Leechburg ; ]?rae-
l.urn; Fayette County, Youghiogheny Biver, Ohiopyle ; Jacobs Greek, LaurelviBe;
Dunbar; Cheat Haven ; Alleyheny County, Alleghany Biver, Butler Junction ; Little
Bull Greek, Tarcntunv (A. Koenig coll.); Deer Greek, llarmarville: Little l)eer
Creek, Busselton ; Bower's Bun. Montrose; Squaw Bun, Asi)inwall: Verona. (D. .\.
Atkinson coll.) ; C^iigley's Bun, Verona; Breakneck Bun, B>akoi-stown Station ; I'ine
Greek, below Bakerstown Station, (D. A. Atkinson coll.); Stone Bun. Tbornhill ;

882 MEMOIRS OF THE CARNEGIE MUSEUM

(xirty's Run, Millvale ; Westview (D. A. Atkinson coll.); Avalon ; Edgeworth, (G.
H. Clapp coll.) ; Schenlev Park. Pittsburgh, (E. B. Williamson coll.) ; Fern Hollow,
Pittsburgh ; Edgewood Park, Swissvale ; North Versailles Township, opposite Stew-
art; Jacks Run, South Versailles Township ; Bost(jn, (D. A. Atkinson coll.) ; Thomp-
son's Run, Kennywood, (F. E. Kelly coll.) ; Carnegie, (D. A. Atkinson coll.) ; Moon
Township, (D. A. Atkinson, B. Graf, E. B. Williamson, A. T. Shafer, Q. T.
Shafer coll.); Thorn's Run, Moon Town.ship ; Flaugherty Run, Moon Township,
(Q. T. Shafer coll.) ; Butler Countij, West Winfield ; Renfrew ; Slippeiy Rock
Creek, Branch ton ; Erie Contifi/, Elk Creek, Girard; Walnut Creek, Swanville ;
Crawford County, Spartan sb u rg ; Linesville ; Mercer County, Stoneboro, (D. A.
Atkinson) ; Mercer; Lairrcncc County, Wampum ; Big Run, Newcastle (D. ( '. Hughes
coll) ; Beaver County, Ambridge ; Baden ; Beaver, (S. N. Rhoads coll.) ; Brady's Run,
Fallston ; Smith's Ferry; ^lonaca ; Waslnngton County, ^lonongahela City; West
Brownsville ; Francis Mine, near Burgettstown ; Taylorstown ; Greene County, Rice's
Landing ; Bates Fork, Deer Lick ; W'aynesburg ; L)eep ^"alley.

New York : Berhimer Couvty, East Canada Creek, Dolgeville, (R. Ruedemann
coll.).

New Jersey : Mercer County, Princeton.

Maryland: \Vashi71gton County, Home's Valley, (F. Silvester coll.); AUeyhany
County, South Cumberland; Corriganville ; Rawlings ; Garret County, Selbysport ;
Stoyer.

West ^^IRGINIA : Morgan Covnty. Cherry Run ; TucJrer County, Blackwater
River, Davis ; Shavers Fork, Parsons ; Monongalia County, Cheat River,- (H. H.
Smith coll.); Morgantown : J'liasants Covvt;/. St. Mary's; WetzeJ County, New
Martinsville ; Mari<lialJ (nunty, Cameron ; (Jliio County, Elm Grove ; Brooke
Comity, (A)lliers; Hancock County. Holidays Cove ; Congo.

Ohio: Harrison County, Bowerstowii ; ('urroll County. New Hagerstown.

North ( 'OKOTJXA : Watauga (ounfy. lUowing Rock, ( Wilcox coll., Exch. Acad.

Nat. Sc. Philad.).

PREVIOUS RECORDS.

Type Locality : North America, (Fabricius) ; Philadelphia, Pa., (Harlan).

Canada : Falls of Uuiatchouan, Lake St. John, Quebec, (Bell) ; Metis and Mata-
pediac Rivens, Quebec, (Bell); Montreal, (^)uebec, (Faxon); Restigouche River,
New Biunswick. (Bell) ; Up.salrpiitch River, New Brunswick, (Ganong): ^Nfiramichi
River. New Brunswick, (Ganong) ; St. John, New Brunswick, (Faxon) ; St. John
River, (irand Falls to Fredei'icton, New Brunswick, (Ganong-).

Maine: Houlton and JMaysville, Aroostock County, (Faxon); Outlet of Moose-
head Lake, Piscataquis (bunty, (Faxon) ; Madison, Somerset County, (Faxon).

ORTMANN : THE CRAWFISHES OF THE STATE OF PENNSYLVANIA 383

Vermont : (Thompson) ; Burlington, Colchester, and t^helburne, Chittenden
County, (Faxon).

Massachusetts: (Gould); Williarastown, Berkshire County, (Faxon); North
Adams, Berkshire County, (Faxon) ; North Crafton, Worcester County, (Faxon).

New York : Lake Champlain, (Rafinesque) ; Ellenburg, Clinton County, (Faxon);
Elizabethtown, Essex County, (Hagen) ; Westport, Essex County, (Faxon) ; Lake
George, Warren County, (Rafinesque) ; Saratoga County, (Rafinesque) ; Fishkill,
Dutchess County, (Rafinesque) ; Newburgh, Orange County, (Rafinesque) ; Port
Jervis, Orange County, (Faxon) ; New York City, (Paulmier) ; Fallsburg, Sullivan
County, (Faxon) ; Fulton Lakes, Hamilton and Herkimer Counties, (Faxon) ; Can-
ton, St. Lawrence County, (Faxon) ; Utica, Oneida County, (Rafinesque) ; Oswego,
Oswego County, (Rafinesque) ; Cazenovia, Madison County, (Faxon) ; Sherburne,
Chenango ( 'ouiity, (Faxon); Berkshire, Tioga County, (Hagen); Ithaca, Tompkins
County, (Faxon) ; Rochester, Monroe County, (Faxon); Niagara, Niagara ( "ounty,
(Hagen) ; Forestville, Chautauqua County, (Faxon).

New Jersey : Schooley's Mountain, Morris County, (Hagen) ; Orange, Essex
County, (Faxon); Trenton, Mercer ("ounty, (Abbott); Princeton, ^Mercer County
(Ortmann).

Pennsylvania : Windliam, Bradford County, (Faxon) ; Headwatere of Loyal-
sock Creek, Sullivan ( 'ounty, (Ortmann) ; Ganoga Lake, Sullivan County, (Ort-
mann); Berwick, ("oluniliia ("cjunty, (Girard) ; Schuylkill River, Philadelphia,
(Hagen); ( 'hester ( 'ounty, (Faxon) ; Bainbridge, Lancaster County, (Faxon) ; Hum-
melstown, Dauphin County, (Faxon); Carlisle, < 'unilicrland County, (Girard);
Pinegrove, Cumberland County, (Ortmann); McKean (ounty, (Faxon) ; Foxburg,
Clarion County, (Girard); Westmoreland County, (Faxon); Pittsburgh, Allegheny
County, (Williamson); Bedford and Loysburg,"' Bedford County, (Faxon).

Delaware: Greenville, New Castle County, (Ortmann).

Maryland : Ilarford ( 'ounty, ( Faxon) ; Howard ( 'ount}', (Faxon) ; Montgomery
County, (Faxon); Frederick County, (Faxon); Washington County, (Faxon);
Cumberlaml, Alleghany County, (Girard); Garrett County, (Faxon).

Distrk.t OF Coi.tTMniA : Georgetown, (Hagen); Washington, (Faxon).

ViRfiiNiA : Alexandria County, (Fa.von); Clarke County, (Fa.von); Staffonl
County, (Faxon); James River, (Faxon); Franklin, Soiithanq>ton County, (Faxon);
Lunenburg, Lunenburg County, (Faxon); Wayni'sljoro, Augusta County, ( Faxon);

"■Fnxon cites " Pnttonville, Bedford County." The nninc of I'littoiiville lins been clmnt;e<l to Lovsibiirii. wliicli
tlie hamlet oriKinnlly bore. It is situated in tbc valley known ns Morrison's Cove, n beautiful »iM)t full of clear moun-
tain streams, formerly aboandiug in brook-trout. The locality must not be confounded with I'attonville iu Delaware
County, (P. O. Fernwood).

384 MEMOIRS OF THE CARNEGIE MUSEUM

Rockbridge (yuunty, ((lirard); Bath County, (Faxon); Pulaski, Pulaski County,
(Faxon); Wytlieville, Wythe (bunty, (Faxon); Smith County, (Faxon).

North Carolina: Kinston, Lenoir County, (Faxon); Newman's Fork, P)lue
Ridge, McDowell County, (Faxon); Black Mountain, McDowell County, (Faxon);
M^ynesville, Haywood County, (Faxon); Roan Mountain, 6,001) feet, (Faxon).

Tennessee: Doe River, ( Jarter County, (Faxon); (^'laiborne County, (Faxon);
Monroe County, (Faxon); McMinn County, (Faxon).

Kentucky : Kentucky River, Hickman's Landing, (Hagen)" ; Cumberland Gap,
Bell ( 'ounty, (Faxon); Smoky Creek, (Jarter County, (Faxon); Little Hickman,
Jessamine County, (Faxon): Albany, Clinton County, (Faxon); Grayson Springs,
Grayson County, (Faxon); Mammoth Cave, Edmonson (*ounty, (Hagen).'*

West ViR(iiNiA : Patterson (Jreek, (Faxon); South Branch of Potomac River,
(Faxon); Williamsport, Grant County, (Faxon); (^{lade Creek, Ivandolph (Jounty,
Faxon); Petroleum, Ritchie (Jounty, (Faxon).

Ohio : Marietta, Washington County, (Faxon); Tuscarawas County, (William-
son); Knox County (Williamson); Licking County, (Williamson); Columbus, Frank-
lin County, (Hagen); Alum Creek, and tributaries of Big Walnut and Big Darby,
Franklin County, (Osborn and Williamson); Yellow Springs, Greene County,
(Faxon); Warren County, (Faxon): ( 'incinnati, Hamilton ('ounty, (Hagen).

Indiana'-': New Albany, Floyd ('ounty, (P^axon); Cave near Paoli. (Grange
County, (Hay); Down's and Connelly's ( 'ave, Lawrence ('ounty, (Hay); Blooming-
ton, Monroe County, (Faxon); Clear Creek, Monroe (Jounty, (Hay); May's (Jave,
jNIonroe County, (Hay); Indianapolis, Clarion ( 'ounty, (Faxon); Irvington, Marion
County, (Hay).

The locality "Lake Superior" (Hagen) has been dropped, since it is, no doubt,
erroneous, (see Ortmann, 1905, p. 135); the same is the case with "Osage River,
Missouri " (Hagen).

ADDITIONAL NEW LOCALITIES.

New York: Altamont, Albany County, (N. Y. State Museum); Mill Creek,
Wilmurt, Herkimer County, (N. Y. State Mus. ); Spencerport, Monroe Co., (^lus.
Oberlin).

Pennsylvania :

Specimens 'preserved in the Academy of Natural Sciences of PhUaddphia : 5717 (Jei--
mantown Ave., Philadelphia ; small stream near Holmesburg, Philadelphia County;

" Not located by writer.

'*The form from Mammoth Cave is not typical, according to Faxon and Hay.

•''Specimens from Indiana differ from the typical form, according to Faxon and Hay.

ORTMANN : THE CKAWFISHES OF THE STATE OF PENNSYLVANIA 385

Roberts Run, Abranis, Montgomery County ; Port Alleghany, McKean County;
Corydon, Warren County.

Specimens preserved in the Departraent of Agriculture, Harrishurg: Buckingham,
Bucks County ; Avondale, Chester County ; Highspire, Dauphin County ; Harris-
burg, Dauphin County; Rockville, Dauphin County; Danpliin, Dauphin County;
Marshrun, Perry County ; Gettysburg, Adams County ; Montalto, Franklin County;
Emmaville, Fulton County; Huntingdon, Huntingdon County; Willianisport,
Lycoming County ; New Albany, Bradford County ; Wellsboro, Tioga County.

^f|•. IF. R. yicC<)V}iell collected t}ii>< species (it tlie fiAloiring Jomlilies : Stream flowing
(jut of Beach Lake, Wayne County; small stream tributary to Delaware River,
Portland, Northampton County ; stream flowing into Lehigh River, Slatington,
Lehigh County ; Schuylkill River, Reading, Berks County ; Tob3''s Creek, Kings-
ton, Luzerne Count}' ; Fish Creek, neai- Stillwater " fifteen miles above Blooms-
burg," (Columbia County ; Montour Run, Greenpark, Perry County ; Big Buffalo
Creek, Erly, Perry County; Conococheague Creek, Chambei-sburg anil Marion,
Franklin County; tributary of Conococheague Creek, Mercei-sljurg, Franklin
County; Laurel Run and Shafer's Run (probably Shaver's Creek, both in north-
eastern part of county), Huntingdon County; Slab Cabin Creek and Thompson's
Spring, State College, Center Count}'; Bear Meadows and branch of Spring Creek,
Boalsburg, Center County; Sinking Creek, Center Hall, Center County; Bald
Eagle Creek and Wallis Run, Milesburg, Center County; Beech Creek, Beech
Creek Station, (Jlinton County; Fishing Creek and tributary. Lamar, Clinton
County; Nipponose Creek, Jersey Shore, Lycoming County; branch of Genessee
River, Ulysses, Potter County.

Ihe ivriter has seen this species at and from the following localities:

Lafayette, Montgomery County, (H. Gera coll.); Leopard, Easttown Towur^hi]).
Chester County, (J. F. Sachse, Philadelphia, coll.) ; Wills Creek, Hyndman, P>ed-
ford County ; Big Meadow Run, Ohiopyle, Fayette ('ounty ; West Branch of Sus-
quehanna, Cherry Tree, Cambria and Clearfield Counties.; Blaii-sville Intei*section,
Westmoreland County ; Springs on Chestnut Ridge, near Derry, Westmoreland
County, elevation 1800 feet; Coalpit Run. Milll)ank, Westmoreland County; Done-
gal, Westmoreland County; Jeanette, Westmoreland County: Alleghany River.
TTultoii, Allegheny County; tributary of Thompson's Run. south of North Pes-
semer, Allegheny County; Sandy Creek and Alleghany River, Sandy Creek. Alle-
gheny County ; Nine .Mile Run, Pittsl)iHgli, A lleghenv County ; Dinsmore. Wash-
ington County ; Summit and ( 'onneautville Station, Crawford County.

Makyland : Sideling Creek, Washington County, (II. A. I'ilsbry coll.. Acad.

386 MEMOIRS OF THE CARNEGIE MUSEUM

Nat. Sc. Phil.); Town (Veek, Alleghany County, (H. A. Pilsbry coll., Acad. Nat-
8c. Phil.); Deer Park, Garrett County, (P. R. Uhler coll.). (See below under (\
(Jioi/eihci^, footnote 2G.)

PvEMAPvKS :

Camharus Ixtrfnni is the crawfish of the small streams in Pennsylvania, and is
exceedingly abundant all over the state.

In spite of its wide distribution over parts considerably different in physical con-
ditions, this species is in Penn.sylvania very uniform with regard to its morpholog-
ical characters (disregarding the variety robusias, to be discussed below). It is true
that in the foregoing description many characters are pointed out which vary within
certain limits ; but these variations are not restricted to certain parts of the state,
but occur everywhere. It is even hard to say of any character that it'prevails in a
certain region. In general there are indications that the species is moi'e fioui-ishing
and also more variable in the western part of the state than in the eastern. This
observation, however, applies chiefly to characters which appear in very old speci-
mens, as for instance, a stronger development of the tubercles on the inner margin
of the hand and on the outer margin of the movable finger. Since the eastern form
is much smaller, such characters, which are only occasionally present in very large
specimens, are not found in specimens from the east, namely, strong sculpture of the
hand and very thick margins on the rostrum.

The most variable feature of this species is the rostrum. Generally it is narrower
and more graduall}-- tapering in very young specimens (PI. XXXIX, Fig. }d and \e).
In older individuals it becomes broader, and is more suddenly constricted into a
longer or shorter acumen. Beyond this there is no rule. The most frequent shapes
are those figured on PI. XXXIX. Fig. l/> and Ir. Tiie one delineated in Fig. 1/is
exceptional. The other extreme is shown in Fig. \o, with margins practically par-
allel, and a very sudden constriction into a comparatively short and broad acumen.
Although this last shape is more frequent in the western part of the state, it is also
found in the extreme eastern portions of the commonwealth.

There is only one character in which regional variation may be observed, and
this is the size of the body. As has been mentioned, in the eastern part of the state
this species is considerably smaller than in the western, and the largest specimens
are found west of the Chestnut Ridge. Individuals 80 nnn. and more in length are
not rare in Westmoreland, Allegheny, Elk, and Lawrence Counties. Specimens
between 70 and 80 nun. long have been found, in addition to the counties just
named, in Crawford, Venango, Potter, Jefferson, Butler, Armstrong, Washington, and

ORTMANN: THE CRAWFISHES OF THE STATE OF PENNSYLVANIA 387

Fayette. All of these are west of the Chestnut Ridge. East of the (.'hestnut Rulge.
but west of the Alleghany Front, specimens over 80 niin. in length are rare; only
one was found at Saml Patch, Somerset County, (86 mm. long). Specimens over
70 mill, in Icnutli ai-e not infrequent here. In the .\llegliany .Mountain region,
(between the Alleghany Front and the Blue Ridge) only a few instances of speci-
mens over 70 mm. in length iiave been found, and none as large as 80 ram. The
largest is from Mc(Jonnelsburg, Fulton County, 77 mm. East of the Blue Ridge
(South Mountain) the length 70 mm. is never attained. In the easternmost extrem-
ity of the state (Xortliampton and Bucks Counties) even the length of GO mm. is
not represented among my material, although I possess large series of specimens
from this region. Thus it appear.s that the size gradually decreases from west to
east. There is hardly any appreciable decrease in .size from south to noi-th. The
smaller number of large individuals from the northwestern section of the state is
very likely due to the fact that large collections were not made in that part of the
state.

Freaks have been observed in several cases. Aberrant forms of the rostrum
have been repeatedly found, atid one variation has been encountered four times in
which the rostrum has a very slightly developed acumen, so that it is almost evenly
rounded off anteriorl}', witli only a small and indistinct median angle or point,
(female, 2-5 mm., Schenley Park, Pittsburgh ; female, 50 mm., Templeton, Arm-
strong County ; male, first form, (34 mm., Branchton, Butler County ; female, 80 mm.,
MoiKjngahela City, Washington County). The rostrum, in these cases, is exception-
ally short, due to a reduction of the acumen. A case of an unsymmetrical rostrum,
with the left angle at the base of the acumen cut off, has also been observed ; this
is clearly a malformation due to some previous external injury.

We may class with the freaks a single specimen in which the carapace possesses
a lateral spine. The specimen is a female (42 mm. long) from Weskit, Armstrong
County, and it has a small, sharp, lateral spine, but only on the left side of the
carapace. This is the more remarkable since it demon.strates the importance of this
specific character. There is not a single other individual among tiie large material
at hand which possesses such a spine, although granulations in its place are not
infre([uent.

Two interesting cases of aljnormally developed sexual characteristics have been
noticed (compare the other ca.ses mentioned under C (Fa.ro)iiits) o/wtvnv/.v).

1. A large female, 71 mm. long, found March 31, 1905, at llollidays C»)ve. Han-
cock County, W. Va., (Cat. No. 74. 491), which is normal in every respect l)Ut one.
antl be.sides, is undoubtedly sexually normal, since it carried under the abdomen

388 MEMOIRS OF THE CARNEGIE MUSEUM

ten young ones, ready to leave the mother, (very hkel}' a number had left already
when the mother was captured). It has on the ischiopodite of the left third perei-
opod the copulatory hook of the male ; this hook is not small or rudimentary, but
strong, and similar to the hook as found in the male of the fii'st form. The ischi-
opodite of the corresponding right pereiopod has no trace of this hook.

2. A specimen, 48 mm. long, was found in P^ern Hollow, Pittslmrgh.'Novemljer,
22, 11)05, (Cat. No. 74. 681). whicli externally (in the sliape of the claws) looks like
a female, but shows very indistinctly the sexual openings of the male, and no traces
of those of the female. Ft also has the first plecjpods of the male of the second form,
but the second pleopods are built according to the female type. Further, it lacks
entirely the hooks of the third jiereiopods. and has a distinct female annulus, of
juvenile type.

This case does not correspond exactly to any of those de.sci'ibed previously. It
resembles to a certain degree one of the cases in C. ohscurus described above (No. 3),
with the exception that here the fii'st pleopods are of the type of the male of the
second form, and that the second pleopods are not of the male, but of the female type.

4a. Cambarus (Bartonius) iurtoni robustus (Girard).
(Plate B, Fig. 2. Plate XXXIX, Fig. 2</ and 2h. Plate XL, Fig. 3.)

Cmiihanis rabustiis Girard, 1852, p. 90 ; Hagen, 1870, p. t-0, PI. 3, f. 167 ; Smitli 1874, p. 639 ; Faxon, 18846, p. 143.
Cambarus harloni rohustns Faxon 1885a, p. (il ; Faxon, 18856, p. 358; Underwood, 1886, p. 367; Faxon, 1890, p. 622;

Faxon, 1H98, p. 649 ; Osburn & Williamson, 1898, p. 21 ; Williamson, 1899, p. 20, 47 ; Hay, 1899, p 959, 966 ;

Williamson, 1901, p. II ; Ortmann, 19U5n, p. 391 ; Ortmann, 19056, p. 135.
Cambarus harloni Williamson, 1905, p. 310.

The differential characters of this form are the following :

Bodij robust, attaining decidedly a more considerable .size than the typical har-
toiri. The largest individuals at hand are a male, first form, fi-oin Spartansburg,
( "rawford County, measuring about 98 mm. (estimated, since rostrum is damaged) ;
a female from Squaw Run, Allegheny County, measuring 94 mm. and a male,
second form, from Puketta Creek, Allegheny Count}^ (A. Kcenig coll.), measuring
101 nun. I have quite a number of males (of the first and second form) and of
females over 90 mm. long. It is also remarkable that specimens of this variety, of
a considerable size (60 to 70 mm.) display characters which are distinctly juvenile,
showing no tendency on the part of the chelce to attain a large size. This tendency
is also evidenced by the fact that the smallest males of the first form at hand are two
individuals measuring 72 mm. (Union ( 'ity and Plulton). From Oberlin, Ohio, I
have .seen a male of the fir.st form, 71 mm. long, while the minimum size of sexually
ripe males of the typical form is 50 mm. for western, and 49 mm. for eastern
Pennsylvania.

ORTMANN: THE CKAWFISHES OF THE STATE OF PENNSYLVANIA 389

TJtc shape of titc carapace i.s similar to that of ('. bartoni, but, in old specimens,
appears slightly more depressed on account of the wider hepatic and branchial re-
gions; G :H :B = 1 : 1.3 to 1.5: 1.5 to 1.7.

The rostrum (Plate XXXIX, Figs. 2f/ and 2/1) is markedly different from the
typical form, narrower, more tapering, and with a longer acumen ; the upper sur-
face is slightly concave. The shape is rather variable. In young specimens of the
typical ('. bartoni the rostrum often approaches the form of C. bartoni robustns, but
on the other hand young specimens of the latter have a narrower rostrum than the
Ibinier. (( "ompare Plate XXXIX, Fig. If and 2//). In many cases the rostrum of the
variety is not longer than in the typical form, but in others it surpasses it, reaching
to the middle, or even almost to the end of the third joint of the peduncle of the
antennula, or to the base or almost to the middle of the fifth joint of the peduncle
of the antenna.

Areola similar to that of the typical form, but with a larger number of rows of
punctures (4-6), whicli is due to the punctures being more crowded, not only on
the areola, but on the whole carapace.

The carapace is often provided with small and sharp lateral spines; the}' are
sometimes obsolete, or replaced by tubercles, or even entirely absent.

Anfoinal scale generally slightly wider than in the typical form, and slightly
longer.

Antennal flagellurii not differing greatly from that of the typical form, and quite
varial)le in length. Tliere are a few cases where it reaches to the end of the telson,
and even slightly beyond, thus surpassing any case known in C. bartoni.

The first j)ereio2)ods (Plate XL, Fig. 3), display remarkable and important differ-
ences from the typical form. The hand has nearly the same shape, but the fiugei-s
are less gaping, and meet all along their edges even in individuals of a considerable
size (retention of juvenile character); it is only in very large specimens that they
are distinctly gaping, but less so than in much smaller individuals of C. bartoni.
Tlie .sculpture of the hand is much more strongly developed. The inner margin of
the hand has a distinct and regular double row of tubercle-s. This double row is a
very important character, and is noticeable in specimens from the size of about 30
nun. ujjward. In very young individuals it is ob.solete, and becomes more and
more distinct with advancing age. Every specimen at hand, without excep-
tion, possesses this character, when the cheUe are normally developed ; but it nuist
be mentioned that in regenerated chela?, which are always recognizable by their
shape, this double row is sometimes indistinct or irregular. Further, there is a tri-
angular depression both on the upper and lower side of the hand at the base of the

390 MEMOIRS OF THE CARNEGIE MUSEUM

immovable finger. I'oth impi-essions are always present in large individuals ; in
younger ones they are indistinct, but are always 'marked liy punctures, which are
much crowded, and consequently by the denser hairs implanted in them. Traces
of the impression on the upper surface are often seen in the typical form, but that
of the lower surface is always absent, or marked only by a slight flattening of the
surface. These two impressions give to the hand of this variety a very strongly
marked marginal keel or ridge. The outer margin of the movable finger possesses
a number of irregularly placed tul)ercles, indistinct, and restiicted to the proximal
part in young specimens, but very distinct, and occupying al)Out two-thirds or
three-fourths of the margin in old specimens. The longitudinal ribs of the upper
surface of the fingers are always well developed, and there is hardly any tendency
in older specimens for them to become obscure, chiefly in the case of the immov-
able finger, where this ril) is always well marked on account of the strongly devel-
oped punctures of the depression accompanying it on the outside.

The ai'mature of the cnrpopodifc. and the mernpfxViic is almost identical with that
of the ty])ical form, but the carpopodite in old individuals is often provided with
accessory k)W tubei-cles on the upper face. The spines of the meropodite are more
distinct and more numerous; those on the distal upper margin (generally two of
them) well developed, even in large individuals; tho.se of the lower margin consist-
ing of two to six in the outei- row (two are rare, found oidy in young ones ; in regen-
erated cheUe as many as eight); and seven to twelve in the iimer row (as many as
fourteen in regenerated cliehe).

All the other cliaracters, including the cohir (see Plate B, Fig. 2), agree with the
typical foi'm. The color of the eggs (in the only specimen ever found with eggs, at
Spartansburg) is prune-purplc (\'1I1, ] ), almo.st black.

There are in the collections of the Carnegie Museum one hundred and forty-
seven specimens of this form, all of which are from Pennsylvania, with the excep-
tion of four, which are from Kentucky.

DL-^TRIBUTION.
LOCALITIES REl'KESENTED IN THE CARNEGIE MUSEUM.
Pennsylvania: Allcylicn;/ CoLditi/, ( "hartiers Creek, Carnegie, (D. A. Atkinson
coll.); Pine Creek, below Bakerstown Station, (D. A, Atkinson coll.); Squaw Run,
near Aspinwall ; Alleghany Uiver, Sandy Creek; Alleghany Uiver, Hulton ; Little
Bull Creek, Tarentum, (A. Koenig coll.) ; Puketta Creek, (A. Koenig coll.) ; McKccit
Couidij, Alleghany River, Larabee ; Warren Count //, Crouse Run, Garland ; Craw-
ford County, Oil Creek and tributaries, Spartansburg ; small tributary of Conneaut

ORTMANN : THE CRAWFISHES OF THE STATK OF PENNSYLVANIA 391

('reek, ( 'oiineuutville station; Erie Couiiti/, French ('reek. Union ("ity; Sixteen
Mile Creek, Northeast, (Miss (!. Kinzer coll.); Walnut (.'reek, iSwanville; Elk Creek,.
Giranl ; Conneaut and Temple Creeks, Albion.

Kentucky : Small stream tributary to Rockcastle River, Livingston, Rockca.stle
County, (E. B. Williamson coll.).

PREVIOl'8 RECORDS.

Type locality : 1 lumber River, Toronto, Ontario, Canada, ((Jirard).

( A.NADA : Don River, Toronto, (Jntario, (Eaxon) ; Weston. Ontario, (Faxon).

New York : Tributary of Racket River, near Tupper's Lake, St. Lawrence
County, (Faxon); Canton, St. Lawrence County, (Faxon); Natural 15ridge, Jeffer-
son ( 'ounty, (Faxon) ; Fulton Lakes, Hamilton and Herkimer Counties, (Faxon) ;
Petersboro, Madison Count}', (Faxon); Sodus, Wayne County, (Faxon); Genessee
River, Rochester, Monroe County, (Hagen) ; Forestville, Chautauqua ('ounty,
(Faxon).^"

Pennsylvania : Squaw Run, near Aspinwall, Allegheny County, (Williamson);
tiibutary of Alleghany River, Port Alleghany, McKean County, (Ortinann).

Ohio: Big Jelloway Creek and tributaries, Knox County, (Osburn and William-
son); Oberlin, Lorain County, (Ortmann).

Illinois : Decatur, Macon ( "ount}-, (Faxon).-'

Maryland: Montgomery Count}', (Faxon).

Virginia : Fredericksburg, Spottsylvania ( 'ounty, (Hagen) ; \\'ytheville, Wythe
( 'ounty, (Faxon).

New Localities :

Pennsylvania: W'aterford, Erie County, (Dep. .Agriculture, llarrisburg).

Maryland: Deer Park, (Jarrett County, (P. R. I'hler coll., see below under C.
diogeites. Footnote 27).'"

RE.M.VRKS:

In I'cnnsylvania this variety is well marked, and might safely be regarded as a
species. Its chief characters are found in the shape of the rostrum and the sculp-
ture (if tlic hand. I ncxcr was in doubt as to this \'nr\\\, with the exception nf
young individuals (less than 30 mm. long), in which the hand does not show its
characteristic features; Inil in such specimens the shape of the rostrum generally

'" Hagen also gives: " Regis Lake, N. Y.", in tlie Adirondncks.

" This locality should be confirmed, see Ortmann, lOll.-)/), p. !;{.->.

" In K()nj;h Knn, Wist Winlield. Bntler County, I'n., I found on .hine 20, 19(M, several joung specimens appnr.
piitly helon;;ing to this variety. I did not take them, expecting to get larger ones, in which hope I was disappointed.
Thus this locality is somewhat douhtfnl.

392 MEMOIRS OF THE CVRXEfUE MUSEUM

gives a clue. This, however, is not the case in rerij young specimens, (less than '20
nnn. long), and such I am unahle to distinguish from the typical form.

The characters are slightly variable, as has been pointed out above, but this
variet}' generally is ver\' uniform in its characters in Pennsylvania. I have not
found any variations worthy of special mention. With reference to the lateral spine
of the carapace, there are specimens which show no trace of it, (.young as'well as old).
In old specimens this spine is often tuberculiform. and in aljout half of the number
at hand there is on each side a sharp, but always small lateral sj)ine. In this respect
there is no difference in the specimens of northwestern Pennsylvania from those
found in Allegheny < ounty.

It seems to me that the southern records for this variety (^Maryland, Virginia,
and also Kentucky)-^, do not refer to exactly the same forni which is found
in the north (( "anada. New York, northwestern Penns^dvania, northern (Jhio).
Hay (1890, p. 966), in the key to the species gives as one of the differential
characters of C hartoni rohudus : "carapace cylindrical, sides nearly parallel as
far forward as cervical groove, then curving abruptly to the base of rostrum,"
while, under <'. Ixaiofii. the carapace is described as " . . . depressed, sides gently
curving toward the fnmt and rear." This cylindrical shaj)e of the carapace is deci-
dedly not present in our northern form ; on the contrary, the depression of the cara-
pace in our rahiif^fiis is, if anything, more pronounced than in the typical hdiioui ;
and our robustus agrees in this respect with ( iii-ard's type from ( 'anada, preserved in
the Academy of Natural I'^ciences, Philadelphia, and which has been examined by
the writer.

On the other hand, our s|)eeimens from Kentucky seem to approach the form
from ^'irginia and Maryland. The shupe of the carapace is more cylindrical, as
Hay describes it, G : H : B = 1 ; l.Oo to 1.2 : 1.2 to 1.3. This .shows that the width
of the carapace at the branchial and hepatic regions is decidedh' less, compared with
the vertical diameter at the gastric region, than in the typical hdrioiii There are
other slight differences in the form from Kentucky : ( 1 ) the rostrum is not quite so
narrow ; (2) the lateral spine of the carapace is absent ; (3) the punctures of the areola
are not so crowded (about three rows), and are similar to those of hartoni ; (4) the
impi'essions of the hand are indistinct; (5) the double row of tubercles on the inner
margin of the hand is different, the outer row being distinct, but the inner consist-
ing of only a few more or less distinct irregular tubercles. All four specimens from
Kentucky are comparatively small, (the largest is 54 mm. long), and thus the two
last described characters may be due to age, although the specimens differ slightly

23 Faxon, 1890; Hay. 1899 ; Williamson, 1905 ; Ortraann, 19056.

ORTMANN: THE CRAWFISHES OF THE STATE OF PENNSYLVANIA 393

from iiurthern iiidividuiils of the same size. The other characters incHne
toward the typical badoni, while the shape of the carapace varies to the other
extreme.

A single male of the second form, about 60 mm. long, from Deer Park, (iarrett
County, Marj'land, sent to me for examination liy Dr. 1'. U. I'hler of Baltimore, was
found under a lot of typical C. Iiartoiii, (supposed to be ('. diojenets). This male
agrees fairly well with the specimens from Kentucky. The cai'iipace is rather cylin-
drical ; there are no lateral spines on the carapace ; the punctures of the areola are
like those of (.'. bartonl ; the cheUc, which are unequal, and apparently both regen-
erated, have rather distinct impressions on the upper surface, but the inner margin
has only one row of tubercles. The rostrum is of the robustu-^-iype. Thus, of the
characters of robustus, only the shape of rostrum and the impressions of the chelte
were present, all other characters being those of typical bartonl.

Specimens possessing a rather elongated rostrum, but with the other characters
of typical bartonl, 1 liave seen associated with individuals of the typical form taken
at Gettysburg, Adams ("o., Pa. (Dep. Agric, HarrLsburg) ; Imt these I have recorded
with typical C. bartoni. (See above, p. 385.)

It is very desirable that the southern form in Maryland, \'irginia, Kentucky, and
adjacent localities, should be investigated more closely. The records at hand, and
the few, immature specimens the writer has seen, do not permit a final conclusion
as to whether we have to deal in the south with a form differing from that in the
north, oi- not. The same reason forbids us to restore our C. robu.stu.s to the rank of
a species, which I surely would have done if the Pennsylvania!! material alone
were to be considered.

In Pennsylvania ('. bartoni robustus is not always associated with C f)arloni. I
found it thus in every case in Allegheny County, in ( 'rawford County, and in War-
ren County. In ^IcKean County I found it associated with C. obsciirns in the Alle-
ghany River at Larabee, but the typical C. bartoni was not there, although occurring
not far away in .small streams and springs. In Erie County C. bartoni was found
only twice, in l"lk ('reek ami \\'alnut ( "reek, associated witli C Jmrtoni robustus, but
then only a single individual of the former was found in each case. At Albion and
Union ( 'ity ('. bartoni robustus alone was present, and I am sure of it, since I hunted
for C. bartoni, but without success. The rich material from Northeast (forty-four
specimens are now in the Museum, but many more were originally in the lot) did
not contain a single C. bartoni. Thus it is beyond doubt that C. bartonl roltu.^lus is
not infrequently found irlthout the typical form, and chiefly so in the most n«»rthern
and western sections of the state.

394 MEMOIRS OF THE CARNEGIE MUSEUM

5. Cambarus (Bartonius) carolinus Erichson.
(Plate A, Fig. 4 : Plate XXXIX, Fig. 3(/ and 3/^ and 9 ; Plate XL. Fig. 4).

Astnciis {Catnbarus) carolitiiin Erichson, 1846, p. 96.

Cambarus diibins Faxon, 18846, p. 114 ; Faxon, 1885fi, p. 70, PI. 4, f. 3, Fl. 8, f. 7 ; Underwood, 1886, p. 368 ; Faxon,

1890, p. C24 ; Hay, 1899, p. 959, 965.
Cambarus carolinus Hay, 19026, p. 38; Ortniann, 1905n, p. 393.
Cambarus {Barfoiiius) ca ral i tiv s Ortmann, 19056, p 120, 135.

B(jdj/ robust, smooth, except for short hairs, chietiy on the chelte in freshly
moulted individuals.

Carapace sul)Ovate, not depressed, l>ut rather compressed in comparison with the
species described above. G : H: B = 1 : 1.07 to 1.1 : 1.1, that is to say, the vertical
diameter and the transverse diameters of the hepatic and branchial regions are
practically the same, the two transverse diameters being only slightly greater than
the vertical. The greatest width of the branchial regions is well forward, immedi-
ately behind the cervical groove.

Cervical <j move deep, not interrupted on the sides.

Areola distinctly longer than half of the anterior section of the carapace
(a : p = I : 1.65 to 1.74), very narrow (v :l — 1 : 10 to 15), with only one. or rarely
two, veiy irregular rows of punctures, which occasionally are almost entirely lacking.

Eostrurn (PL XXXIX, Fig. oa and 3//) slightly curved downward toward the
tip, broad and short, never reaching beyond the distal end of the second joint of
the peduncle of the antennula, but generally only to the middle of it, being some-
times even shorter than that. Upper surface slightly concave, with elevated mar-
gins. Margins straight, sub-parallel, or slightly converging toward the tip, sud-
denly contracted into a broad, short, triangular acumen. Basal angles of acumen
rather sharp, but without an}- trace of marginal spines. These angles are empha-
sized l)y the sudden disappearance of the slight swelling of the lateral margins,
which are not at all swollen on the acumen. Acumen pcjinted. but point short.
Postorbital ridges short, almost parallel, ending bluntly anteriorly.

Surface of carapjace punctate, granulated only on the hepatic region, and some-
times with a few indistinct granules immediatelj' behind the cervical groove on the
branchial region. No lateral spine. External orbital angle rarely or not at all
marked, generally formed by a rounded or slightly angular, insignificant projection,
but never with a spine. Brancliiostegal spine formed by a small, often indistinct,
tubercle.

Abdomen always distinctly shorter than the carapace, narrower than the latter
in the male, almost as wide as the carapace in the female. Anterior section of tehon

ORTMANN : THE CRAWFISHES OF THE STATE OF PENNSYLVANIA 395

Oil tlie posterior lateral corners with one or two spines. Posterior section semi-ellip-
tical, distincth' wider tlian long, about as long as the anterior section.

Efistoma with posterior part comparatively long, liardly one and one-half times
as broad as long ; transverse groove indistinct and close to posterior margin .• an-
terior median depression also indistinct, and thus the posterior part of the epistoma
appears ratiier flat and smooth. .Vnterior section constricted at base, semi-circular
or semi-elliptical or subquadrate, rarely with a median anterior point, often more or
less truncate anteriorly, or even slightly emarginate. Transverse diameter never
greater than longitudinal, as great as the latter or shorter.

Antennula with a small tubercle on the lower margin of the ba.sal joint.

Antennal peduncle without distinct spines or tubercles on the two proximal,
joints.

Antennal scale short and small, slightly longer than the rostrum, and not reach-
ing beyond the distal end of the fourth joint of the antennal peduncle. Spine of
outer margin strong. Laminar j^art only slightly wider than the spine.

Flagellum short, not reaching beyond the third abdominal segment in the male,
and not ])eyond the second sogniont in the female, but often hardly longer than the
carapace.

First 'pereiopods (IM. Xi,, I'ig. 4) short, not very robust, not undergoing much
change with age, and not differing much according to sex. Hand ovate, broad and
depressed. Surface punctate. Inner margin of palm convex, with a single row of
distinct tubercles, larger proximally; occasionally tliere is a second, incomplete row
inside of and parallel to this. Outer margin smooth and n)unded proximally for
a short distance, but soon becoming angular and forming a distinct ridge along the
edge in the region of the base of the immovable finger. This ridge has a regular
row of deep punctures, giving the distinct appearance of serrations along the outer
margin of the hand. Fingers as long as, or slightly longer than the palm, .slightly
gaping at the base in both young and old individuals, straight. Outer margin of
moval)le finger with punctures, but very rarely with tubercles. Cutting edges with
a few iiicgular tubercles in tl)e proximal half Upper surface of each finger with
a low i-ilj, bordered by rows of punctures.

Carpopodite slightly longer than wide, about as long as the palm, with a deep
longitudinal sulcus above. There is always a strong, more or less pointed, spine on
tlie inner n\argin. directed obliquely forward, and a strong, often spiniform. conical
tulK'ivle in the middle of the anterior margin of tlie under side, (rarely obsoleteV
The tubercle at the lower articulation with the hand is low and indistinct. Rarely
there are accessory tubercles, which, however, are never spiniform. The most fre-

396 MEMOIRS OF THE CARNEGIE MUSEUM

(luent are a proximal tubercle on the inner margin, and one between tlie two larger
spines first mentioned, and another just behind the base of the large spine of the
inner margin.

Merojtodifc smooth, w^ith 1-3 indistinct tul)ercles near the distal end of the upper
margin, often entirely oljsolete. Lower side with two rows of spiniform tubercles.
The outer row consists of 2-6 (if only 2, they are followed l)y a few undulations
produced by punctures); the inner consists of (J-ll tubercles. Outer articular tulier-
cle with carpopodite without spine. All spines of the first pereiopods are indistinct
in very young specimens.

Ischiopodite of third pereiopod hooked in the male. Hook of the male of the
first form strong, subconical.

Co.TOpod/te of fourth pereiopod in the male with a prominent, blunt, and slightly
compressed subconical tubercle.

Fivst pleopods of the male (Plate XXXIX, Fig. 9) similar to those of C. hartuni.

Annuhts veniralis of the female likewise of the type of C. bartoni, but less trans-
verse, and the posterior margin more swollen and elevated, while the anterior is
hardly elevated at all, l)ut depressed.

Size. — The largest male of the first furm at hand is from Dunbar, Fayette
( 'ount}', and measures 67 mm. in length. The largest female is from ( Jliiopyle,
Fayette County, and measures 80 mm. in length.

Color (Plate A, Fig. 4). — Whole body rather uniformly orntige-chrome (Ridgway,
1886, VII, 13) to chinese-ornnge (VII, 15), very brilliant in fresh shells, shading to
orange-ntfons (VII, 12) and crcu'in-color (VI, 20) on the sides. Color most intense
on anterior pavt of carapace and on the claws. Abdomen ordiigr-chrome, shading to
salnio'ii-color (VII, 17) or fcrrugiiicovs (lY, 10), or odivaccous-hnff (V, 13). (Jhelfe
varying from o/'<n/yr-rA/'07rtr to .s7//(/ /•;/-;■('/ (VII, I'i). Legs chincsc-onvngc to solinov-
eolnr and fcrrngineous. (Jften a brown or Ijlackish coat of mud covers a gi'eat part
of the body, obscuring the colors. The t-olor of young s[)ecimens is semitransparent,
with more or less red prevailing, but the rostrum and chehe are always distinctly
red. Color of eggs salvion (VII, 17) to salmon-huff (IV, 19).

There are one hundred and thirty-eight specimens in the ( 'arnegie Museum ;

ninety-three from Pennsylvania, thirty-six from West Virginia, and nine from

Maryland.

DISTRIBUTION.

LOCALITIES REPRESENTED IN THE CARNEGIE MUSEUM.
Pennsylvania: Weslmorcland Count g. Jones Mills; Faijdte Con nig, Dunbar; In-
dian Creek; Rainier Park, Ohiopyle ; ISovicrset Count g. Windber; Listie ; Rock-
wood ; Myersdale.

ORTMANN : THE CRAWFISHES OF THE STATE OF PENNSYLVANIA 397

Maryland : Garrett Counlij, Selbysport.

West Virginia: J'rcston (Joxmty, Reedsville ; Tucker Countij, Parsons; Mineral
Count ij, Schell.

PREVIOUS RECORDS.

Type locality : < iroeiiville, Greenvi-Ue ("ounty, S. C, (Erichson and Faxon,
I885((, i)|). U, 56).

Tennessee: Cumberland Gap, Claiborne County, (Faxoiil.

Virginia : Pennington Gap, Lee County, (Faxon).

West Virginia : Soutlnvestern West Virginia, (Hay) ; Terra Alta (( 'ranberry
Summit), Preston County, (Faxon).

Indian Territory: Cherokee Nation, (Faxon). -^

New Locality : -' Blowing Rock, \\'atauga County, North Carolina. (J. P.
Moore coll., Acad. Nat. Sci. Philadelphia).'-"

KEM.VRKS:

This species, the Red Crawfish of the mountain regions, occupies, next to C
projiiiiqaus, the smallest area in this state. Its morphological characters are very
uniform, not only in this .state, liut also in the neighboring parts of West Virginia
and Maryland. The chicjf variations, as already mentioned in the description, are
found in the armature of the chelipeds, but they keep within comparatively narrow
limits. The rostrum, wliich is (piite varialjle in C. bartoni, is here very constant,
only the degree of convergence of the lateral margins and the length of the acumen
varying to a certain extent, (See Pi. XX.Xl.X. fig. 3o. and 3/;.) Of course, we must
disregard monstrosities, under which lu'ad 1 place two cases, (from Dunbar and
Parsons), where the rostrum has almost no acumen at all, being rounded off apically.

The armature of the meropodite and carpopodite varies as described above ; the
carpopodite in jjarticular showing a various number of tubercles, though they never
become spiniform as in ('. vionoiujalcmh. The lower outer margin of the merop-
odite has always more lliaii one spine, when spines at all are visible, which is gen-
erally not the case in veiy young individuals.

"This locality needs coiilinimtion, .see Ortinann, 1905b, p. 13.5.

"This species is abundant in certain parts of Somerset and Fayette Conntics, Pa., and well known to the natives-
I have seen chimneys in abundance at Conlhiente, Somerset County, which undoubtedly helonn to this species, but was
not able to secure specimens, my time being limited. I have seen a specimen at Flnnigan, 4 miles north of Soniertleld,
Fayette Co., and one from llumbertston, F.iyctte Co. (O. T. Cruikshank coll. ). Reports received from farmers, always
emphasizing the red color and burrowing habits of the crawfish in question, arc the following : Great Meadow Run,
west of Ohiopyle, Fayette County ; Millrun, Fayette County ; Ursina, Somerset County ; Salisbury, Somerset County.

'* These specimens (collected June, 1893, and, according to Professor Moore's recollection, dng out of holes) agree
in all essential points with our mateiial. only the rostrum is nairower.

398 MEMOIRS OF THE CARNEGIE MUSEUM

I tliink 1 have observed that in specimens from tlie south (Maryland and West
Virginia) there is a more pronounced tendency to develop a second row of tuber-
cles at the inner margin of the hand. Such specimens, with a few additional tuber-
cles, occur also in Pennsylvania, but in West Virginia they are more frequent, and
the additional row becomes more distinct and more regular. There is moreover a
specimen from Parsons, W. Va., in which traces of a third distal row are visible.
On the other hand specimens with one row only are also found in West Virginia.

No interesting freaks or monstrosities have been observed.

't>

6. (Jambarus (Bartonius) monongalensis Ortmann.
(Plate B, Fig. 4. Plate XXXIX, Fig 4a, 4b and 10. Plate XL, Fig. 5.)

C'ambarus dubins 'Williamsou, 1901, p. 11, (non tlubin^ Fa.xon).

Cnmbmtis monongalensis Oitmann, 1905o, p. 395.

Cambarus (Barlotiius) monongalensis Oitmann, 190.56, p. 120.

This species being closely allied to C. cdiv/inus, the description will be given in
terms of comparison with the latter.

General shape ofh(x1i/, carajiace, cervical tjroorc, and areola identical with that in
a caroHnns. G:H:B = 1: 0.9 to 1.1 : 1 .1 to 1.3.

Rostrum. {F\. XXXIX, Figs, ia and 4//) markedly different from that of ('. caru-
linus. It is as long as that of the latter species, or slightly shorter in the average,
never reaching beyond the middle of the second joint of the antennula, and is uni-
formly narrower. The upper surface is (ioncave. The margins are less sharply
elevated, the elevation decreasing gradually to the apex. Margins distinctly con-
verging, and contracted to form the short, triangular acumen, but the contraction
is not so sudden as in ('. car(ili)iiis, so that the angles at the base of the acumen are
not so sharp, liut I'ounded. Acumen with short point. Postorbital ridges short
and )-athcr indistinct, distiiutly divergent posteriorly.

Sculpture of carapace and other details as in ('. caroVenvs. The alnJomen i\\\i\ tclsaih
are also identical. l)ut the lateral corners of the antei'ior section of the telson have
only one spine.

Epistoma similar to that of (J. cawlinus, but the truncated (subquadrate) shape
prevails in the anterior section, which has often a small median anterior point.

Anteniui and antennula similar to those of C. Carolina^, but antemied scale shorter,
not much longer than the rostrum, and reaching only to the middle of the fourth
joint of theantennal peduncle.

Fifst pcreiopnjs (PL XL, Fig. 5) in general shape similar to those of C. carol inus,
but hand not quite so broad, and there are im])ortant differences in the armature.
The inner margin of the hand invariably has only one, l;)ut a distinct, row of tuber-

OKTMANN : THE CRAWFISHES OF THE STATE OF PEFNSVLVANIA 399

cles. The outer margin is rounded, witli no indication of angulation, and entirely
lacks the serrations of ('. carolinus, the punctures producing the latter forming in
this species no regular row.

The carpopodite is much more spinous. The large spine of the inner margin is
well developed. The spine in the middle of the anterior margin of the under side
is tuberculiform, and the tubercle at the lower articulation with the hand is insig-
nificant, lint there always are additional distinct spines, which are well developed,
although smaller than the large spine of the inner margin. A spine on the proxi-
mal end of the inner margin is always present, and also a spine between the large
spine of the inner margin and the anterior tubercle of the lower side. (If the latter
spine is missing, the claw has been regenerated.) Often there are other spine.s.
The proximal spine of the inner margin may be double, and there may be one or
several spines or tubercles near the base of the large spine of the inner margin,
anterior or po-sterior to it.

Meropodite witli the distal tubercles of the upper margin very indistinct, gener-
ally missing. The outer lower margin is formed by a smooth keel, which has in
most cases only one small tubercle near the distal end, which may be obsolete. In
rare instances there are two tubercles. If there are more, the daw has been regen-
erated. The inner lower margin has a row of 6-12 spiniform tubercles; if less,
the claw has been regenerated.

All the other organs are similar to those of ('. c<troUnu.% more particularly the
first pleopods of the male (PI. .\.\.\IX, fig. 10) and the annulus of the female.

Size. — The largest male of the first form, from Edgewood Park, Allegheny
County, is 6<S mm. long; the largest females (same locality and Monaca, Beaver
County), are 76 mm. long.

Color (PI. B, Fig. 4). — In specimens with fresh shells the middle of the cara-
pace and abdomen is of a beautiful marine-blue (Ridgway, 1886, IX, 2) ; the hepatic
and branchial regions are cijanine-hlue (IX, 3) and china-blue (IX, 13), shading
toward the lower margin io j)ale-blue (IX, 16). The marine-blue of the abdomen is
restricted to the anterior parts of the segments ; the posterior parts and the epimera
are chinorblue shading to pale-blue. Margins of rostrum maroun-purplc (\'III, 9).
The hand is ci/anine-blue above, shading toward the lower side to cohaU-blue (IX, 12),
azure-blue (IX, 15) and pale-blnc. .\t the base of the dactylopodite there is a good
deal of roi/al-purple (VIII, 7). The dactylopodite is ci/aninc-bluc, the outer margin
violet (VIII, 10). The finger-tips are orauijc-rcrmilion (\'I f. 12), shading proximally
to salmon-color (VII, 17) and whitish. The carpododite ol' the chelipeds is marine-
blue, shading to cijanine-bl uc and French-blue (IX, 6). Tubercles and spines of

400 MEMOIRS OF THE CARNEGIE MUSEUM

hand and carpopodite pale vinaceous-pinh (ligliter than IV, 21). Basal joints of
antennae cyanine-hlue ; flagelluni annulated daldia-pvqjie (VIII, 2) and very pale
lildc (lighter than VIII, 19). Pereiopods pale-hlue, upper edges shading to china-blue,
near the bases irhitc. Lower side of l)ody whitish, on the abdomen suifused with
china-blue and pnle-blue.

These brilliant colors fade more or less in old specimens, but the via rinc-blue
always remains the ground-color. A brownish or blackish deposit of mud often
obscures the colors, and such specimens often appear blackish-blae all over.

Young individuals are semitransparent, with a distinct pale-blue hue on the
■ abdomen and chehe, and heUotrojje-purple (VIII, 18) on the carapace.

Distinct color varieties are rare, and the few observed will be mentioned below.

The color of the newly laid eggs is hazel (IV, 12) or ocliraceous (V, 7) ; later on
they are vinaceous-buf {V, 15) on one side, pinkinli- white on the other.

The Carnegie ^luseum possesses two hundred and seventy-nine specimens of this
species, two hundred and thirty-six of which are from Pennsylvania, and forty-three
from West Virginia.

DISTRIBUTION.

LOCALITIES EEPKESENTED IN THE CARNEGIE MUSEUM.

Pennsylvania : Westmoreland County, Hill, (opposite Leechburg) ; Braeburn ;
Dundale ; Jeanette ; Allegheny County, south of Logan's Ferry, (C. V. Hartman
coll.); Hulton, (R. Dornberger coll.); Wilkinsburg, (D. A. Atkinson coll.); Edge-
wood Park, (type locality); Nine-Mile Run, Pittsburgh ; Fern-Hollow, Pittsburgh ;
Schenley Park, Pittsburgh ; Squaw-Run, near Aspinwall, (D. A. Atkinson) ; North
Versailles T(jwnship, (opposite Stewart) ; Jack's Run and Long Run, South Ver-
sailles Township ; Boston, (D. A. Atkinson); Thompson's Run, Kennywood, (F. E.
Kelley coll.) ; Carnegie, (D. A. Atkinson) ; Moon Township, (A. T. Shafer coll.) ;
Lashell's Hollow, Moon Township : Beaver County, Doctor Heights, Monaca ; Wash-
ington County, Francis Mine near Burgettstown ; Taylor.stt)wn ; Monongahela (Jity ;
West Brownsville ; Fayette County, Smithfield ; ( "heat Haven ; Greene County, Deer
Lick.

West Virginia : Hancock County, C'ongo ; Hollidays Cove ; Brooke County, Col-
liers ; Ohio County, Elm Grove; Marshall County, Cameron; Nuss ; Monongalia

County, Morgantown.

PREVIOUS RECORDS.

The only previous records are those given by Williamson (as C. dubius),

Schenley Park and Fern Hollow, Pittsburgh, and iMoon Township, Allegheny

( 'ounty.

OKTMANN : THE CRAWFISHES OF THE STATE OF PENNSYLVANIA 401

ADDITIONAL LOCALITY.
The writer has seen this species at Sandy Creek, Allegheny County, Pa.

REMARKS.

The Blue Crawfish is rather abundant in the region indicated by the above
localities, and apparently represents a geographical differentiation of C. carolinus,
the Red Crawfish. The points in which it differs from the latter species, aside from
color, are slight, but are constant according to my observations.

The rostrum is markedly different from that of C. carolimis, although slightly
variable. It always is smaller than that of the latter species and narrower, with less
distinctly marked lateral angles. The lateral margins are swollen, but the swelling
is less marked, and does not suddenly decrease at the lateral angles. The degree of
convergence of the margins is variable, but generally much more pronounced than
in the Red Crawfish; cases like that figured in Plate XXXIX, Fig. 4b, are rather
rare, in fact, this case forms the extreme in this direction.

In the shape of the hand, the rounded outer margin and the absence of .serra-
tions on it are other striking characters of this species ; and the carpopodite is dis-
tinguished by the larger number of spiniform tubercles, as described above. The
outer lower margin of the meropodite generally has a blunt and smooth keel, with
only one small tubercle near the distal end (which may be absent). Among my
material I had only ten specimens which revealed an exception, where two such
tubercles were present, and in onl}^ two of them were these tubercles present on both
chelipeds. In the others they occurred only on one side. There ai-e instances in
which a large number are found, but always in claws which have been regenerated.

Aside from tlie slight variations indicated above only a few exceptional cases
have been encountered in which niarkLMl deviation from the above description
of the prevalent colors occurs. The blue ground-color is always present on the
anterior part of the carapace and the chehv. In a rare variation, which has
l)een observed about half a dozen times, the grounil-color of the posterior part of the
carapace and parts of the abdomen are more or less purplish {attricitla-jinrplf, \'I1I,
3). Furthermore a single adult female was found at Monaca in whiih all red tints
were absent ; the blue of the bod}' was very clear, the margins of the rostrum were
blue like the carapace, the finger tips were whitish, all spines and tubercles were
pure white, and the antennal flagelluni was a pure blue. Specimens in which the
margins of the rostrum have the same shade of IjUie as the carapace are not
infrequent.

402 MEMOIRS OF THE CARNEGIE MUSEUM

Other freaks are occasionally found, as for instance a specimen without an acumen
on the rostrum, the latter being evenly rounded off; a specimen with the immov-
able finger of the left hand with a doaljle tip, the outer one the larger, and a spec-
imen with the movable fingers of both liands only half as long as usual, thick, short,
and conical. Such cases apparently are due to some previous injury, and suggest
nothing of special intei'est.

All the variations mentioned above are rare and are not restricted to certain
parts of the range of the species, so that we do iiot distinguish any regional varieties.

7. ( 'amp..\rus (Bartonius) diogenes Girard.
(Plate A, Fig. 3 ; Plate XXXIX, Fig. 11 ; Plate XL, Figs. 0 and 7.)

Camhmvfi (liog<7Hx Girard, 1852, p. 88-, Faxon, 1884i, p. 144 ; Abbott, 1884. p. 1157; Faxon, 1885", p^ 71 ; Fa.xon,
ISesfc, p. 359 ; Faxon, )885f, p. 140 ; Underwood, 1886, p. 368 ; Faxon, 1890, p. 624 ; Ortmann, 1891, p. 12 ;
Hay, 1896, p. 489, Fig. 7 ; Faxon, 1898, p. 650 ; Osburn it Williamson, 1898, p. 21 ; Williamson, 1899, p. 20, 48 :
Hay, 1899, p. 959, 961 ; Harris, 1900, p. 267 ; Williamson, 1901, p. 11 ; Hay, 1902«, p. 235 ; Ortniann, 1905o, p. 398.

Cambarvs nbiKvs Haf;en, 1870, p. 8], pi. 1, T 39-42, pi. 3, f. 163, pi. 9 ; Smith, 1874, p. 639 ; Foibes, 1876, p. 5, 19 ;
Bnndy, 1877, p. 171 ; Bnndy, 1882, p. 183; Bnndy, 1883, p. 403.

Cambarus dioqenes ludovidamis Faxon, 18846, p. 144 ; Hay, 1899, p. 959, 962.

Cambarus dubins Osburn and Williamson, 1898, p. 21, ( non dubiiis Faxon).

Cambanm {Biirlonhis) (/inycnf.s Ortmann, 190.56, )>. 120, 135.

Bodi/ robust, smooth, except for short hairs, chiefiy on the cheke in fresh shells;
the hairs also to a certain degree persist upon the hand and fingers in older indi-
viduals.

(Airapace subovate, not depressed, but rather compressed. G' : H: B = 1 : 0.88 to
1.0:1.06 to 1.2; that is to say, the transverse diameter of the carapace is very
slightly greater than the vertical, at the hepatic region sometimes even less. Great-
est width of branchial regions well forward, not far from the cervical groove.

Cervical groove deep, not interrupted on the sides.

uircola distinctly longer than half of the anterior section of the carapace (a :/> =
1 :0.6l to 0.75), very narrow, and generally obliterated in the middle; that is to
.say, the two lines bordering the branchial regions are in contact in the middle of
the carapace. In rare instances a small space is left between them, upon which
there is no room for punctures.

Rodrum more or less lanceolate, rather narrow, but not very long, reaching
hardly beyond the distal end of the second joint of the peduncle of the antennula,
being often shorter. Upper surface slightly concave, with elevated margins. Mar-
gins not much swollen, the swelling gradually disappearing toward the tip, con-
verging, straight, or slightly convex, contracted to form a short triangular acumen.
Basal angles of acumen indistinct, rounded, without any trace of marginal spines.

ORTMANN : THE CRAWFISHES OF THE STATE OK PENNSYLVANIA 403

Point of acumen short. Postorbital ridges short, terminated bluntly in front,
slightly divergent posteriorly, ending in a low, indistinct swelling.

Surface of carapace punctate, slightly granulate on the hepatic region, and with
a few granules on the branchial region, immediately behind the cervical groove.
No lateral spine. External orbital angle present, distinct, angular or rounded, but
without tubercle or spine. Branchiostegal spine formed by a small, often indistinct,
tubercle.

Abdomen about as long as the carapace, or very slightly shorter or longer, nar-
rower than the carapace in the male, markedly wider and about as wide as the
carapace in the female. Anterior section oi telson with 1-3 (generally 2) spines on
the posterior lateral corners. Posterior section semi-elliptical, slightly wider than
long, and about as long as the anterior section.

Episioma similar to that of C. carolinus and monoivjaleims, comparatively long
and narrow, rather Hat, and with the anterior section semi-circular, senii-elliptical,
or truncate and subquadrate, with or without median point, and about as long as
wide.

Anlennula with a small tubercle on the lower margin of the basal joint.

Antennal peduncle without spines or tubercles on the proximal joint.s.

Antennal scale small and short, slightly longer than the rostrum, and reaching to
the Ijase of the fifth joint of the peduncle of the antenna. Spine of outer margin
strong; laminar portion not nmch wider than the spine, its inner margin parallel to
the outer margin of the spine for a considerable distance.

Flagellum short, often only as long as the carapace or even shorter, never reach-
ing beyond the second abdominal segment.

First pereiopods (PI. Xfy, Fig. 6) stout and very robust in old individuals; not
much different in the male and female, except for their very large size in old males.
Hand ovate, broad, depressed. Surface punctate. Inner margin of palm convex,
with two irregular rows of tubercles, and a few scattered tubercles on the upjier
surface near the marginal rows. Outer margin smooth, rounded proximally.
slightly angular distally. Fingers at least one and one-half times as long as palm
(the latter measured from articular tubercle with carpopodite to articular tubercle
with dactylopodite), gaping at the base, straight both in young and old specimen.s.
Cutting edges with a number of strong but irregular tubercles ; one tubercle at
about the middle of the edge of each finger is generally tiie largest. (>uter margin
of movaV)le finger with more or less distinct tubercles at tin' |)roximal end. I'ppi-r
surface of each finger with a low longitudinal rib, bordered by rows of punctures.

Carpopodite aljout as long as wide, shorter than palm, with a deep longitudinal

404 MEMOIRS OF THE CARNEGIE MUSEUM

sulcus aljove, and a few more or less distinet tuljercles between sulcus and inner mar-
sin. A strong pointed spine in the njiddle of the inner margin, straight, and di-
rected obliquely forward. A tubercle or spine on anterior margin of lower side, and
a low tubercle at articulation with hand. A few additional tubercles may be pres-
ent on the inner margin and the lower side, but they are very rarely spiniform.

Merojwdite smooth, with 1-3 indistinct tubercles near the distal end of the upper
margin. Lower side with an outer row of 1-4, and an inner row of 7-11 spiniform
tubercles.

Ischiojwdife of third pereiopods hooked in the male ; hooks in the male of the
first form strong, subconical.

Coxopoditc of fourth pereiopods with a strong, slightly compressed tubercle.

First plcopods of male (PI. XXXIX, Fig. 11) similar to those of C. bartoni, the
tip of the inner psivi, however, tapering gradually to the point.

Annulus vcntralis of female similar to that of C. curulinns.

Size. — The largest specimens at hand from the eastern part of the state are a
male (first form) and a female from Ridley Park, both 83 mm. long. From the
western part of the state I have a male of the first foi'm from Nine-^Iile Run, Pitts-
burgh, which measures '.)2 \n\n. in length, and a male of tlie second form from Mill-
vale, Allegheny County, which is U3 mm. long. The largest female is from Nine-
Mile Run, and measures 97 mm. in length.

In the west this species attains a much larger size. The maximum length has
been recorded by Hagen, 4.5 in. = 115 mm. However, the Carnegie Museum pos-
sesses a male of the first form from Bluffton, Wells ('ounty, Indiana (collected by E.
B. Williamson), which is now (in alcohol) 122 mm. long, but measured 124 mm.
when alive.

Color (PI. A, Fig. 3). — The color is rather variable within certain limits, but the
ground-color is similar to that normally seen in crawfishes, brownish or greenish.

Cround-color on carapace and abdomen from oUvc-green (Ridgway, 1886, X, 18)
to raii'-umber (III, 14), mummii-hroion (III, 10) and ferrwjiiieous (IV, 10), shading on
the sides through c^m') (III, 18) or russet (III, K^) to fawn-color (III, 22) and whitish.
Margins of rostrum rufous (IV, 7) or fer rug ineo us (IV, 10). The hand is taivny-olive
(HI, 17) to burnt sienna (IV, 6) and rufou% shading to olive-ijcUow (VI, 16) toward
the outside. At the bases of the fingers there is often a distinct shade of olive-green
(X, 21). The finger tips are rufous, the tubercles of the liand crcdni-biiff' {V, 11) or
irhifi^h. The legs are ocliruceous-lmff (Y, 10) with nUvr-biiff (W 11), or rnssct (III, 16)
with olive-green (X, 18) at the joints. Lower side of body pale rufous or pale
orange-huff (VI, 22), or whitish. The antennal flagellum is annulated dark olive-

ORTMANX : THE CRAWFISHES OF THE STATE OF PENNSYLVANIA 405

green and whitish. The relative amount of green and brown changes very consider-
ably with different specimens, but in general we may say that green prevails in the
young, and brown in older specimens.

Color of newly laid eggs huf (V, 13); when more advanced 2^>'i''ne-purple
(VIII, 1), or indian-purple (VIII, 6) on one side, cream-color (V. 20), or didij-whitc on
the other.

In the Carnegie ^luseum there are altogether three hundred and twenty-three
specimens of this species, of which twenty are from eastern and two hundred and
sixty-six from western Pennsylvania. Two specimens are from Maryland, five
from West Virginia, twenty-four from Indiana and three from Iowa ; while one speci-
men is from each of the states of Delaware, Ohio, and Kansas.

DISTRIBUTION.
LOCALITIES REPRESENTED IX THE CARNEGIE MUSEUM.

Pennsylvania: Bucka CouiiUj, Penns Manor; Philadelphia Coicnlij, Essington ;
Delaware Count;), Ridley Park ; Marcus Hook ; Greene Count;/, Waynesburg ; Rice's
Landing; Fa;jefte Count;/, Smithfield ; Dunbar; Pennsville ; Washiyiyton Count;/,
Francis Mine near Burgettstown ; Beaver Count;/, Baden ; Racoon Township ; Alle-
gheny Cbw?i<?/, Troup's Retreat, Moon Township, (E. B. Williamson coll.); Stowe and
Neville Townships, (Atkinson, Graf, and Williamson coll.); Edgeworth, (Mrs. E.
Courtney coll.); Westview, (D. A. Atkin.son'coll.) ; Millvale ; Vwn Hollow ami Nine-
Mile Run, Pittsburgh ; Schenley Farm, Pittsburgh, (F. E. Kelly coll.); Silver Lake,
Pittsburgh, (E. B. Williamson coll.) ; Bruce's Ice Pond, Pittsl)urgh, (Atkinson and
Williamson coll.); Carnegie, (D. A. Atkinson coll.); Jack's Run, North Vei-sailles
Township; Rankin, (O. T. Cruikshank coll.); Squaw Run, near .\spinwall ; Mon-
trose ; Ilarmarville ; Ru.sselton ; between Gibsonia and liakei-stown Station ;
Thornhill ; Westmoreland Count;/, Donohoe ; New Alexandria; Dundale ; Reser-
voir of McGee Run, Derry ; Blairsville Intersection; Livermore ; Kiskiminetas
. I unction; Indiana Count;/, Homer; Creekside ; Jefferson Count;/, Punxsutawney ;
Armstrong Count;/, Long Run, Avonniorc Station : Kittanning; Butler Count;/, Ren-
frew; Branchton ; Lawrence County. Wampum ; Mercer County, Mercer.

Delaware : Sussex County, Seaford, (S. N. Rhoads coll., exch. Ac. Nat. Sci..
Philadelphia).

Maryland: Kcrd County, Chestertown, (E. G. X'anatla coll.. ext-h. Ac. Nat.
Sci., Philadelphia).

West Virginia: Hancock County, Congo; Brooke County, CoUiei-s; Wetzel
County, New Martinsville.

406 MEMOIRS OI\THE CARXEGIE MUSEUM

Ohio: FranJdin Crninfij, Columbus, (E. B. Williamson coll.).

Indiana: WcIIs ihnnti/, Bluffton ; Twin Lakes; Craigville ; Liberty ("enter;
Uniondale; Blackford Count;/, Hartford < 'ity ; l)e Kulh (Aninfi/, Newville (all coll.
by E. B. Williamson).

Iowa: Greene Count u, Cooper, (J. B. Hatcher coll.); Lee County, Denmark (R.
L. Baird coll.).

Kansas : Douijlas Count;/, Lawrence, (S. Prentice coll.).

PREVIOUS RECORDS.

Type Locality : Wa-shington, D. ( '., (Girard).

New Jersey : Trenton, ]Mercer ( "ounty, (Abbott).

Maryland: Worcester County, (Faxon); Dorcliester County, (Faxon); Caro-
line County, (Faxon); Baltimore County, (Faxon); St. Mary County, (Faxon). ^"

Virginia: Accomac County, (Faxon); Northampton County, (Faxon) ; Alex-
andria County, (Faxon); Prince William County, (Faxon); Fredericksburg,
Spottsylvania ("ounty, (Faxon); Petersburg, Dinwiddie ('ounty, (Hagen).

North ("arolina: Kingston, Lenoir County, (Faxon); Wilmington, New Han-
over Count}', (Faxon).

Pennsylvania: Deny, Westmoreland County, (Faxon); Pittslmrg, Allegheny
(Vjunty, ( Williamson ).

Ohio: Oberlin, Lorain ('ounty, ((Jsburn and Williamson); Knox ('ounty,
(Williamson) ; (Jolumbus and Lockbourne, Franklin County, (Faxon) ; Montgomery
County, (Williamson).

Michigan: Detroit, Wayne ('ounty, (Faxon).

Kentucky: Louisville, Jefferson ('ounty, (Faxon); Bee Spring, Edmonson
County, (Faxon); Mammoth (Jave, Edmonson (Jounty, (Hay).'^*

Indiana : Kendallville, Noble County, (Bundy) ; Riverside, Laporte County,
(Faxon); Kokomo, Howard County, (Faxon); Mechanicsburg, Henr}^ County,
(Bundy); Irvington, Marion ('ounty, (Hay); North Salem, Hendricks County,
(Hay) ; Greencastle, Putnam (Jounty, (Hay) ; Bloomington, Monroe (^'ounty, (Hay);
Knox County, (Faxon).

2' Faxon also gives Deer Park, Garrett County, (Coll. P. R. Uhler). I have doubted (19056, p. 136) the correct-
ness of this locality. In order to be sure I have asked Dr. P. R. Uhler of Baltimore to send to me the specimens upon
which this record was founded, and Dr. Uhler very kindly complied with my request. There were two males of the
second form and four females in the lot, all belonging to C. baiio}ii, and representing the typical form, with the excep-
tion of one male, which I have identified with the southern form of C. bnrloni robusliis (see above, pp. 391 and 393).
Thus this record (Deer Park) for C. diogenes is to be dropped.

-*The localities in Jefferson and Edmonson Counties are given by Faxon with a ? ; but Hay's record of this species
from Mammoth Cave tends to confirm their correctness.

ORTMANN : THE CRAWFISHES OF THE STATE OF PENNSYLVANIA 407

IijJxoTs: ('liicafio, Cook County, (Hagen) ; Evaiistoii. Cook County, (Hagen) ;
i>a\vn Riilge, Marshall County, (Hagen); AbingtlDU, Knox ( 'ounly, (Faxon);
Decatur, Macon County, (Faxon): IjcUcvillc, St. Clair County, (llagun).

WiscoNsix : "Abundant in Wisconsin," (Bundy); Uacine. Racine County,
(Faxon); Creen ('ounly, (l-'axon); Appleton, Outaganu<- (I'unty, (Faxon).

Minnesota: Fort Snelling, Hennepin ('ounty. (I'^ixon).

Iowa: l)avcii|)ort, Scott County, (Faxon): i'cllii. Delaware Count}', (Faxon) ;
Belniond, Wright County, (Faxon).

Missouri: St. Louis, St. Louis (.'ounty, (Faxon); Carroll County, (Faxon).

Kansas: Leavenworth, Leavenworth County, (Faxon); Lawrence, Douglas
County, (Harris).

Arkansas: Paragould, <jireene (ounty, (Faxon); Fayetteville, Washington
County, (Faxon).

Mississippi: Monticello. Lawrence County, (Hagen).

Louisiana : New Orleans, (Hagen).

Wyoming : Cheyenne, Laramie County, (Faxon).

Colorado: Clear Lake, (Faxon)-"; Boulder, Boulder County, (Harris)'".

RE.ALVRKS.

CamharuH (liot/encs occupies two areas, in the United States, which, according to
oui' |in'siiit knowledge, are separated from each otlier ; a western and an eastern.
Both areas enti'r Fennsylvania, the one extending over a large portion of the south-
western territory of tills stall', tin' other heiiig mueli smaller and restricted to the
southeastern cxln'iiiity.

1 have closely studied the material at hand, and have found certain dillerences
between eastern and western specimens, which however are very slight, and not
always constant; yet a tendency to a morphological separation between the eastern
and western forms seems to be indicated. Faxon (1H85((. p. 7".^) has already called
attention to some of these differences.

The description given al)ove refers chietly to the ((islcrn form of this specie.".
Speciiiieiis from western I'emisylvania show the following ilitlei-eiices :

1. Arcolii ill most cases not entirely obliterated. There are, indeed, casfs in the
eastern form whric tjie two lines bordering the branchial regions are not in contact,
lint they are rare. In western Pennsylvania the latter condition is rather the rule,
although specimens in which lioth lines unite, forming in the ini<ldle only one line.

*" Location uiikiio>Mi to the wiitur.

'" Professor T. 0. A. Cockerell lins sent to me for exniiiinntion a joiini; ninlc collected ( tctolier 7, l!)ir>, in ii sniiill
stream mar r.oiilder. Although very Hmiill it clearly lu'lonia;* to this species.

408 MEMOIRS OF THE CAENEGIE MUSEUM

are b3Mio means absent. There is some variability in this ehanieter. (lenerally a
very narrow space is left between the two lines, which does not leave room for any
punctures. But it is a curious fact that the lareola is widest in specimens from
Fayette and eastern Greene (-ouuties. In these localities specimens with an entirely
obliterated areola are exceedingly rare, and specimens with the areola so wide that
there is room for one irregular row of punctures are rather frequent, (Pennsville,
Dunbar, Smithfield, Fayette ( 'ounty ; llice's Landing, (Ireene County). Such
specimens with punctures on the areola, which is accordingly wide, are scarcely
found anywhere else. I possess only one from rittsbui'gh.

2. Rostrum, in all eastern specimens at hand, with a more or less distinct acu-
men. In the western form there is a distinct tendency to render the acumen ob-
scure. Indeed there ai'e many speciniens which have the acumen exactly as in the
eastern form, but there are as many where it is not marked, the margins converging
evenly to the tip. In such specimens the rostrum assumes a rather regular lanceo-
late shape, and appears somewhat more elongate and narrow. Howevei', it is actu-
ally not longer than in the eastern form.

3. The swelling at the posterior ends of the pusinrliildl ri(l(jes is sometimes more
distinct in western specimens.

4. In oni- western form the rjifriml nrJiiUi! (iin/lc is rarel}' angular, l)ut generally
blunt or rounded. In some cases it is very slightly developed.

f). There are specimens in western Fennsylvania where the posterior section of
the telson is longer and more tapeiing. In extreme cases this is I'ather .striking, the
posterior section being distinctly longer than the anterior, and longer than wide.
This latter condition is never found in eastern specimens. On the other hand there
are many western specimens which do not differ in this respect from the eastern,
and many transitional conditions have been observed.

6. Avtennal sciile in the western firm often slightly wider than in the eastern,
and with a stronger spine. This difference, however, is very slight.

7. <'h(hr in the western form (PI. XL. Fig. 7) of slightly different shape, but this
difference always holds good, provided the chela has not been regenerated, and is
otherwise normally developed. The inner margin of the palm in the eastern form
has always two rows of tubercles, while on the upper surface there are at the best
only a few minute, scattered tubercles, chiefly near the base of the dactylopodite.
In the western form the two rows of tubercles are also generally distinguishable,
but often the inner row is in-egular, and merges into the scattered tubercles present
upon the inner half of the upjier surface. These latter tubercles are invariably
present, and are much more numerous than in the eastern form. The dactylopodite

ORTMANN: THE CKAWFISHES OF THF, STATE OF PENNSYLVANIA 409

of llie western form is generally shorter. While in the eastern form it is at least one
and one-half times as long as the palm, in the western form this relation is the
maximum, and is due to a proportionally heavier and stronger development of the
palm as compared with the fingers. (This does not hold good for regenerated
cheliu, in which the dactylopodite always is considerably longer in proportion to
the palm.)

The tubercles of the cutting edge of the dactylopodite are slightly different in
both forms. In the eastern the third or fourth is generally much larger, and, just
before it, there is a gap, as if one tubercle were suppressed. This produces a distinct
excision at the base of the finger, which is always more or less marked, even in
rather young individuals, so that the fingers always appear gaping at the base (PI.
XL, Fig. 6). In the western form the fourth or fifth tubercle is larger than the
rest, but there is no distinct gap anterior to it, the three or four proximal tul)ercles
being ratlier equidistant. They decrease slightly in size from the first to the fourth,
so that a slight emargination is indicated. I'ut this emargination and the large
tubercle following it are well <listinguishable only in larger individuals ; in younger
specimens they are rather indistinct, or entirely wanting, so that the basal gaj) is
absent, and the fingers are in contact all along their edges.

The differences in the relation of dactylopodite to palm, and in the tuljercles of
the dactylopodite, give to the whole chela of the western form a difierent aspect,
the hand appearing rather more massive with shorter fingers. (See PI. XL. Figs.
G and 7.)

8. The co/o/'.s in western specimens are more vivid, and with more contrast.
Eastern specimens are more uniformh' russet or olive-green, with no oil-green at the
l»ase of the fingers, while the latter tint is very characteristic of the western form, at
least in specimens of a certain size. Old western specimens, when fresh, are ratlu-r
brilliantly colored.

1 think 1 am able to recognize and t(j distinguish ea.stern and western speci-
mens, chiefly by the help of the characters of the chela?, if the latter are normally
developed; but I do not know whether it would be advisable to distinguish lioth
forms l)v varietal names. Tlie latter maybe necessary in future, when the forms of
C. dioyenes from the regions west of Pennsylvania have been more clo.sely studietl.
I think I am able to see certain differences in the western specimens in our collec-
tions, but the material is too poor to be sure of it.

No remarkable freaks or malformations have been observed in this species, with
the exception of a few color variations. They are the following:

1. In I'ern Hollow, Pittsburgh, a specimen was found in a stagnant [lool, (i to

410 MEMOIRS OF THE CARNEGIE MUSEUM

10 inches deep, in yellowisli brown mud. Its color was entirely yellowish brown,
mottled lighter and darker, and no trace of olive-green was present. This appa-
rentl}' was a stray specimen.

2. A large male of the first form was found at l>unliar, Fayette County, the
ground-color of which was salmon-color (VII, 17), the abdomen lnif(V, 13), irlntish
on the sides. The red was brightest on the cheke, with- traces of green- between the
tubercles of the hand, and the lower side of the chehe and body were dirty brown-
ish yelluw. This is) apparently a case of albinism.

IV. EC^OLOGY AND GEOGRAPHICAL DISTRIBUTION.

A. Ecology.-"

Satisfactory conclusions as to the relation of geographical disti'ibution to the
physical conditions of the country can only be expected, if we know all about the
ecological laws governing the different species. VC'Ah reference to the seven species
of crawfishes present in Pennsylvania, we shall see that the ecological conditions
are quite varied, and the single species behave very differently. Thus it is necessary
to discuss these facts first, before we attempt to study the distribution.

Three main types of ecological conditions may be distinguished among t>ur
crawfishes. We pos.sess species which generally live in the larger rivers ; (jther
species which favor the opposite extreme, preferring the groundwater, where it is
not far from the surface, and appears in the shape of springs and swamps; and
intermediate between these two conditions is a species which selects the smaller
streams for its home. We may conveniently call these "the river species," "the
mountain-stream species," and "the Imrrowing species."

1. TltP River Species.

Cambariis Jimosns, Caniharns propiiKjims, Cumharns ohscurus.

Although princi})ally living in the larger rivers of the state, these species ai-e

not entirely' restricted to them, being able to live in any larger body of water, I'un-

ning or stagnant, providing it is permanent. Thus these forms, in some cases, go

'■" " Ecolog}-," the science of the "relation of organisms to external conditions,'' is the oldest term, created by
Hieckel (" Oecologie," in " Generelle ilorphuhigie da- Orgauisme," 18(56). The term "Bionomics," which is often used
in its place, was first introduced by E. Ray Lankester (in the article: Zoology, in Encyclopaedia Britannica, 9th ed.,
1888, p. 803), and subsequently, but independently, (as " Binnouiie") by J. Walther (F.inleitung in die Gciiloyie als
hislorische IVissensrhaft" 1. Bionomie des Meeres, 1893, p. XX). The term "Oecologie" was revived chiefly by E.
Warming, (Plantesamtund. Gruudtrick af den lukologiske Plantegeografi, l'-9o). The term " Ethologie " introduced
by F. Dahl (Verh. Ges. Naturf. & jErzte, Bremen, LXIII, 3. 1891. p. 123) has a wider sense, including also what
we here call "life-history."

ORT.MANN : THE CRAWFISHES OF THE STATE OF PENNSYLVANIA 411 '

far up stream into the smaller tributaries of our rivers, sometimes almost to their
sources. The only condition which stops them in an up-stream migration seems to
be the character of the watercourse, which must not be too rapid and rough. This
is a very important fact, and largely explains the absence of these species in the
mountainous regions of the state. On the other hand, these species are by no means
averse to quiet bodies of water, such as ponds and lakes, and although tlie parts of
Pennsylvania where these species are found are singularly free from lakes, craw-
fishes are almost regularly found in them, and even in artificial ponds, reservoii's,
etc. It has been observed tliat in ponds and lakes these species seem to tiirive
exceptionally well.

Among the three species belonging to this class, there are certain differences.
Cambarus limosu!^ of the eastern part of Pennsylvania has its main abode in the
quiet streams of the lowlands. It goes up stream for a certain distance, but rarely,
and only under exceptional conditions, (see below), is it found in streams which are
somewhat rough. Its center, at least for tliis state, is in the lower part of the Dela-
ware River, where it is under the influence of the tides. Here it prefers the muddy
banks, living among the water weeds, and congregates often in large numbei-s at the
mouths of small streams tributary to the river. In fact the latter places are the
most favored, since this species loves to hide under stones, and it is chiefly at the
moutli of streams that stones are found in this part of the Delaware. Further up
stream, beyond the reach of tlie tide in the Delaware, and in its tributaries (Nesh-
aminy Creek, Schuylkill River, Brandywine Creek) and in the Susquehanna and
Potomac drainages, this species is generally found hiding under stones, as was
first reported b}' Abbott (1873, p. 80) with reference to the Delaware River at Tren-
ton, N. J. ]3ut such is not the exclusive habitat of C. limosiis. It is very often
found in quiet ponds, in ditches or canals, where there are no stones to afford cou-
cealnu'ut. In these places it frequents patches of weeds (J^tllisneria, etc.), often in
considerable numbers. From such places (ditches of the Delaware meadows at
'I'lviitim) it was reported by Faxon (1885a, p. 88). C. limosits is generally found in
very shallow water, but sometimes at a considerable depth. 1 captured a few speci-
mens in a quiet cove of the Delaware River at Penns Manor, Bucks County, at the
woodwork of a pier, at a depth of from six to eight feet (Sept. 15, 1!K)5), and fre-
(luently got numbei-s of it in creeks and canals (Schuylkill Canal, Manayunk ;
Delaware and Raritan Canal, Princeton), in the water weeds, at a depth of from two
to four feet. Altliough this species loves to hide under stones, and although it
scoops out the dirt under stones, it is by no means a Imi rowing species. 'I'lic hol-
lows made under stones are very insignificant, and I have never olwerved that it

412 MEMOIRS OF THE CARNEGIE MUSEUM

makes holes in the l^anks of streams. Faxon (l(S85a, p. 89 j reports that Mr. Uhler
found this species near Cumberland, Md., in " holes in the bottom and sides of a
canal," but whetlier these were made by the crawfish, or were cracks and joints
between stones, remains doubtful. In the lowkmds in Maryland this species,
according to tlie same authority, is found under stones in rivers and creeks. We
may say of (J. limosus that it is of all the species of this state tlie one which most
decidedly prefers the quieter water of large rivers, canals, and jionds ; that it
likes to hide under stones, but is not at all averse io muddy Ijottoms and masses of
vegetation.

The latter trait distinguishes it from the species of the western rivers, CamJxtras
obscurus, which dislikes muddy bottoms (without stones) and vegetation. In fact,
this is so general a rule, that it is vain to look for ('. ohscurns in any part of a river
which has no stones. Only in rare and exceptional cases have I found it not hiding
under stones, apparently' being forced to do so by necessity. I observed this in two
cases : in the Allegheny River at Larabee, iMcKean ('ounty, and the Shenango
River at Linesville, C'rawford County. In both cases the river runs through peaty
soil (through the Pymatuning Swamp at Linesville), and it was only after a long
search that the s{)ecies was discovered, when I struck jjlaces where stones were lying
in the watei-. But it was interesting to note that at l)Oth places the supply of stones
was apparentl}' not sufticicnt to accommodate all the specimens, and so a number
of them had to be content with a shelter atlbi'ded by the peaty banks, where they
had built short, hoiizontal holes, not more than a few inches long, clo.se to the edge
of the water. These holes are apjiarently only temporary, and are often abandoned
and changed, since a number of them were seen on the banks above the present
water level, which wei-e built and iidiabited at a previous higher stage of the river.
('. obscurus does not love vegetation. The patches of iJiaidhera americaua, so fre-
quent in our rivers, do not harbour many crawfishes, although they are not entirely
absent from them ; but the}' do not hide undei' these plants and their roots, but
under stones. They always scoop out a hollow under the stone selected, and bring
out the mud and gravel, throwing up a small rul)l)ish pile in front of the hole,
which, however, is soon obliterated by the current. The crawfishes ai'e easily found
bs' noting these rubbish piles. They rarely go into deep water (possibly only in
winter), but always are close to the banks in shallow water; liut on the other hand
they never go out of water. In the mountains of western Pennsylvania this species
is generally absent, and it is appai'ently the roughness of the streams which causes
its disappearance. The stones, under which it hides, must be rather permanent in
their position, and must rest upon a bed of mud, sand, or gravel, to afford congenial

ORTMANN: THE CKAWFISHES OF THE STATE OF PENNSYLVANIA 413

conditions. In the niountain streauiis tlie rocks are rolled over very frequently, not
only at high stages of water, but also under ordinary conditions, and this api)arently
does not suit the tastes of this species, and may be even directly dangerous. Since
the general direction of the inigratiou of this species in western Pennsylvania was
and is up.streain, it is evident that falls and rapids in the mountain regions present
effective barriers, In tlie ponds and lakes of western Pennsylvania, connected with
the Ohio drainage, this species is very abundant, but here also it always selects
stones under which to hide.

Cdmbarus propinqinis is restricted to Lake Erie and the lake drainage. It lives
ill the tributaries of the lake, exactly under the same conditions as C. obscnru.i. In
the lake itself it has been found on two occasions. I'r. 1 >. A. Atkinson collected a
minil)er at Presque Isle in the l)ay, but particulars as to their habitat were not
recorded. The only other specimen from the lake was collected l)y myself on the
sandy and gravelly beach near Miles Grove, thrown out by the surf, but alive. It
does not seem to be very abundant in the lake, or at any rate seems to favor
only certain places, and we may presume that places with stones and rocks on
the beach and not too much exposed to the surf are the projjer localities in which
to look for it.

Camhariis fropmqmi s sauhorni in ( Hiioand West Virginia is found under exactly
the same ecological conditions as its representative forms in Pennsylvania.

Nothing was known hitherto as to the ecological habits of C. obscurus and p''"-
jnnqmti), except the short notice of Hay (1896, p. 498), that in Indiana C i>ioiiin-
quus lives " in the smaller streams hiding under stones, concealed in short burrows
along the banks, or resting quietly on the bottom."

2. The Mountain Sfrram Species: CamlxirKS hartoui.
Conspicuously diifering from •the River Species," Camhaniis harhii I favors the
rough streams of the mountains, hills, and the u[)lands generally, an<l is absent from
the large rivers. The size of tlie .stream may vary. In fact it goes up to the very
sources and is found in the s|)rings. The amount of water ma}' be very small. In-
deed it is frequently found in streams which dry out superficially during the hot
season. But in such cases water is always present at a certain depth. The varying
and often scanty supply of water forces this species to accommodate it-self to these
conditions, and thus it has Ijecome to a certain extent a burrowing species. It
always selects stones to hide under, an<l in larger streams with a permanent .supply
of water is satisfied to scoop out a liollow under th.e stone after the fashion of ' '.
obscarus. i>ut very often the burrows are more complex, consisting of a hole going

414 MKMOIKS OF THE CARNEGIE MUSEUM

down to a depth of a foot or even more. These burrows are found along tlie banks
of the streams, and the opening is often not in the water, but away from it, but
rarely more tliau a lew feet. The deej^est l;)uri-ows ai'e found in late summer and
fall, when tlie small streams are almost or entirel}^ dry. Then necessity compels
the ci'awfish to dig deep to ivaeh the underground water. 1 have observed burrows
eighteen inches deep in a vertical direction (see Plate XTJ, Fig. 1). Under these
conditions a consideralile amount of dirt (mud, sand, gravel), is removed from the
hole, and this is piled up in more or less regular mounds at the entrance of the hole,
often assuming the shape of " chimneys," whicli may be fully equal in .size to those
of the typical chinuiey-builders. Here we see the origin of this habit. ('. hartoni
is not an haVjitual chimney-builder, 1)ut is content to hide under stones and to scoop
out shallow holes when the stream has plenty of water. But when the supply of
water becomes scant it has to dig down to reach it, and the burrows and nmd-piles
are the natiu-al consequences of the attempt of the crawfish to accommodate itself to
these peculiar conditions.

The manner in which the l)urro\vs are constructed, and the "purpose" of the
chimneys will be discussed below when we come to consider the true burrowing
species, and it may be remarked here, that everything said with reference to the
latter holds good also for C. hartoni.

The roughness of a stream presents no obstacle to the presence of '"'. hartoni.
Indeed, it prefers small streams which descend in cascades and fall from the hillsides,
provided the rocks lying in them are stati(jnary enough. It goes to tlie \ery ui)i)er-
most springs and is frecjuently found there associated with C. 'luononijuleuais or C.
caroUnus, and also may be found near (J. (Iio(ifii('.-<. 1 have observed cases where C.
harto7ii occupied holes, which were apparently built l)y .specimens of these other
species, and am able to give the following instances. Digging for C. tnonoiKjiiUvxis
at West Brownsville, Washington ( ountv, I found in a large and wide hole a female
(J. hartoni (with eggs). The individual was much too small for this hole. To all
appearances an old (abandoned?) hole of '''. inonungalensis was here occu]iied by
('. txvrtoni. Similar observations were made at Avonmore Station, Armstrong
( 'ounty, where in the swampy ground of the valley of Long Kun a colony of ('. d'axj-
enes was found, and several ('. (liof/fvcs were taken. In two holes, however, a half-
grown specimen of C harloni was fovmd, and again these holes were nuich too large
for them. This place was about fifteen yai-ds distant from the stream in which C.
hartoni was abundant. Another similar case was observed at Creekside, Indiana
( 'ounty.

(jioing down stream (*. hartoni remains abundant, as long as the character of the

ORTMANN: TIIK CRAWFISHES OF THE STATE OF PENNSYLVANIA 415

stream is inaiiitained ; after that it becomes scarce, but it does not disappear entirely,
and ill western Pennsylvania is frequently found associated with (\ ohsaini-^ in
eastern rcimsylvania with (!. limosns. In the large rivers it is generally entirely
absent, and, if louiid. it is at the inoutli of small streams, or at places where there are
springs on the banks. Here it becomes evident that temperature plays an impor-
tant part. The mountain streams, which are the favorite haunts of C. hartoni, are
characterized all the year round by a rather uniform, but comparatively low tem-
perature. Ill winter the temperature of the water goes down to just above the
freezing point, but generally remains slightly higher (in running water about 35°-
40° F.); in sunnner the ma.\imuin of these streams rarely goes above 60°, and does
so only temporarily for a few days, while in the larger streams it remains for weeks
above 70°, and may go up to H()° or even more. (The temperature of the Ohio
River at JJaden, Ik-aver County, on August 26, 1905, was 78° F. on a compara-
tivel}' cool day.) That it is tem[)erature which affects distribution is evident in
summer, when in western I'eniisylvania in the warm water of the rivers C obscums
is found, but where there are springs on the banks discharging perceptibly cooler
water into the river, C. hartoni suddenly appears.

It may be mentioned that I once found this species under very peculiar condi-
tions. At New Hagerstown, Carroll County, Ohio, I discovered numerous burrows
in the black muck of a swampy meadow at the bottom of a small valley, which I
took first for burrows of C. diogeiies. But I was unable to get any diogaies, every
hole investigated being occupied l>v C. Ixirtoni (about half a dozen were taken).
This part of the meadow was clo.se to a hillside, at the foot of which were numerous
.springs with a lew stones, also sheltering specimens of ('. Inirtoui. < >n the other
side of the valley, which was al)out 100 to 200 feet wide, was a small stream with
sandy and gravelly bottom, and a few stones, where also a few C. hartoni were
present. The laigest number of specimens was present in the swampy meadow,
which is rather exceptional, but finds its explanation in the scarcity of stones in
this locality.

The variety <'. hartoni rohiu^tus in general agrees with the typical form as con-
cerns ecological t-oiiditions, especially in tliat it prefers rough, rocky streams. How-
ever, it was found preferably in streams of a larger size, avoiding the smaller head-
waters. As Williamson (HXH.p. 11) puts it: "at the headwatei-s" (Sjuaw Run,
Allegheny County, is taken as an instance) "hartoni is found : following down the
stream roh n si u.'i is noticed; then an occasional ohscurun; till linally hartoni becomes
rare antl disappears; then rohudus disappears; and further down ('. oh.scurus is the
only species."

416 MEMOIRS OF THE CARNEGIE MUSEUM

Since tliose parts of the stream which are inliabited by C. hiuioiii rohHsfits are
always well supplied with water, tliis form does not need to make extensive bur-
rows, and I have never observed regular ehinnieys.''-

The ecological conditions under which ('. Ixnioiii occurs were to some extent
previously known. Goodman (1833 (1842), p. 293) gives a good account of them'*'
as observed in small sti-eams near Philadelphia. According to Abbott ( 1873) it is
found near Trenton, N. J., burrowing in the muddy baidvs of ditches and sn)all
streams, rarel}^ of the river (Delaware). This, however, is nc^t the usual condition,
as we have seen al)0ve. Faxon (188^)(^, j). 63) says that it prefers cooler waters of
mountain regions or uplands, living under the stones in clear streams and in
springs, which is the usual condition under which it is found in this state. How-
ever, that there are variations in its habitat, occasioned by exceptional conditions,
is seen from the case mentioned above from the state of Ohio, from Abbott's account,
and from the observations of Dr. J. Sloan as reported by Faxon (/. c), according to
which, in southern Indiana, it is found in ponds and still water, not in running
streams. This is, however, not always the case in Indiana, since, according to Hay
(1896, p. 489) it is found in "springs and streams of clear ruiuiing water, where it
hides under stones or dies short burrows into the Ijanks."

3. The Burnnvhig Species.
Cantharus caroliitas, Qmiharus nujiunujalcnsls, Cdnihanis dloyenes.

a. General habitat.
The burrowing species are always found at a certain distance from oi)en water,
although often in close proximity to streams, ditches, or ponds; l)ut never, under
normal conditions, in them. Exceptions are very rare, and only accidental, and
found chietl}' in the case of young individuals which have not settled down ])erma-
nently, or of individuals which have been disturbed.^'' These species, however,
always depend on the presence of water, but it is the groundwater which is inhabited

'^Slnifeldt (1896, p. 27) figures a chimney of C. hmtiini rvhnsliis from Dear Wasliiugton, D. C. Why Shufeldt attrib-
utes this chimney to this form, I do not understand. He says that he studied burrows near Wasliington, " many of
these were of C. diogfurs, others were of C. barloni rubiislus, wliich I found abundant in Montgomery County, Md."
The specimen which built tlie chimney figured was not taken by Shufeldt, and he says that in the vicinity anotlier bur-
row was opened which contained a C. (liogitim. According to the description of the hole belonging to the chimney, it is
too deep and complex to belong to C. bditmii, and I do not see any reason for not regarding it as belonging to C. diiigenes.

'^The crawfish hole, eight to ten inches deep, with a wider chamber at the end, under stones in a small stream,
with the opening in the water, undoubtedly belongs to this species.

"A case where young specimens of C. iliugenes were found in numbers in open water by Dr. D. A. Atkinson will lie
discussed below. (See V. ) This case is also to he regarded as exceptional.

ORTMANX: THE CRAWFISHES OF THE STATE OF PENNSYLVANIA 417

by them, and thus they are found at places where the groundwater is near the sur-
face, in springs and swamps. In order to reach the water these species have to dig
a hole in the ground, wliich often goes down through a considerable amount of dry
soil, i)ut it is always iilled witli water at the bottom.

The three species belonging to this class differ slightly with regard to the selec-
tion of their localities. C. carolinus chooses the mountains, and is found in springy
places on the highest parts of the Alleghany plateau. The most favored localities
are high valleys with a '• hard pan," that is to say a layer of stiff clay below, which
serves to keep the groundwater within a few feet of the surface. In such places the
surface is often apparently dry, l)ut upon digging down fresh and clear spring-water
is found at a depth of one to three feet, and the holes of this species go down to the
" hard pan " in order to reach the water. C. monongalensi.'i favors similar conditions,
3'et it does not live in the mountains, but on the foothills west of the Chestnut
Ridge. (The physiographic classification of these features will be discussed below).
In this region extensive valleys with clay bottoms are rarely found, and thus
C. movov(jaleiisl.^ is content with the more restricted deposits of clay found on the
hillsides. Such localities, however, are very abundant in this region, and wherever
there is a spring and a certain amount of clay this species occurs. It prefers the
cool spring-water, and if the spi'ings collect to form a small swamp, this species is
found on its up])cr margin, not in the swamp.

G. diogeiies does not haunt springs to the same extent as (.'. caroliims and ('.
monongalensl'i. It is sometimes found under similar conditions as the other two
species, but generally at places where a spring or small stream spreads out to form
a swamp. It is also abundant in swampy ground along the borders of ditches and
streams, and in swamps formeil in depressions of the valleys of the large rivei-s
(abandoned o.x-bows). In the formerl}' glaciated area of the state it prefei-s kettle-
holes. Like C. monongalensvi it rarely occui*s in the .soft mud of swamps, but
generally along their borders, where the firmer ground affords a better ciiance
to dig more permanent holes. In consequence of the habit of preferring swamps to
springs, C. dioynies is generally found at a lower elevation than C. mmlinus
and monongalen-aiis, where it comes into contact with tlu'in. The two la.st named
forms occupy the region of the clear and cool spring-water, while ( '. dlugcius appi-ai-s
a little further down stream, where the water is not so clear, and in summer
not so cool. In and near swamps the water in the holes of C. dingoics is often
stagnant and muddy (even sewage is not much objected to by this species), while
in the holes of the other two species there is always fnsh and cKar spring-water
bubbling up.

418 MKMOIKS OF THE CARNEGIE MUSEUM

h. Shape of the burrows. (See PI. XL, Figs. 8 and 9, PI. XIJ.)

The burrows of these species (and also of C. bartoni) are to a certain degree alike,
although they are very vai'iable in depth and shape, so that there is very little uni-
formity. Only a few features are common to them. From the more or less dry
surface they go down to the groundwater, where there is generally a kind of a pocket
or widened chamber (PI. XLI, lugs. 5 and 6). The width of the hole corresponds
to the size of its inhabitants. It seems that one and the same individual perma-
nently uses the .same hole, although one and the same hole may be oceujiied by dif-
ferent individuals in succession, for an old abandoned hole may be occupied l)y a
young specimen. This happens chiefly in localities where the holes are much
crowded. There are places where the ground is fairly honeycombed with them," and
under such conditions a new hole may interfere with an old one, when a young
specimen after attaining the proper size begins to Ijuild its own burrow, as it invari-
ably does. If the old hole is abandoned the young specimen may take advantage
of it, while in the alternative case, a fight ensues which ends in the expulsion or de-
struction of the weaker.

Each hole is always occupied by o/u' individual only, with two exceptions. The
first is the case of mating couples, when one adult male of the fir.st form and one
female are found in one and the same hole. The second is when the young of a
certain size are associated with the mother in the hole of the latter.

The holes have all manner of shapes (see PI. XL, and PI. XLI), They may con-
sist of a single shaft only, or may be more complex, branching oft' in various direc-
tions, and may have more than one opening at the surface. The chaml)er may be
well marked or indistinct, and there may be several chambers. The chambers may
be simple widenings of the hole, or may form side pockets. The direction of the
descending shaft is rarely more or less vertical, and if vertical in the upper part, it
generally soon assumes a slanting direction, and sometimes it is irregularly spiral.
Shorter or longer branches may go off' at the sides, and these may end blindly or
may ascend to the surface. At the bottom side-branches may be absent, or may be
developed to a considerable extent, running either horizontally or vertically. On
steep hillsides, or along the banks of ditches, the general direction of the burrows is
very often horizontal, the outward opening being lateral (PI. XLI, Figs. 2, 'A, 7).

The depth of the holes depends on the distance of the level of the groundwater

'5 1 have seen this on the largest scale in the case of C. cnroliniis in the valley of Upper Decker's Creek near Reedsville,
Preston County, W. Va. The whole valley, for two or three miles, offers favorable conditions for this species, and
thousands of chimneys ujay be seen everywhere, coming up even between the railroad ties of the Morgantown & King
wood Railroad.

0I;TMANN: TUE crawfishes of the state of PENNSYLVANrA 419

from the surface. The holes are driven clown by the crawfish to such a depth that
a good supply of water is at the bottona at all seasons. Where the water appears at
the surface, or is very near to it, the holes are sometimes hardly a foot deep. Gen-
erally they are considerably deeper, as much as two iind three feet. They certainly
at limes go even deeper than this, but I never tried to dig at places where such con-
ditions prevailed, that is to sa\', where from all appearances the level of the ground-
water was more than three feet from the surface. Such conditions were not infre-
quently met with in the case of C. carol inus.

In a general way we ma}^ say that the holes of (\ bartoni are very simple
(PI. Xl>, Fig. 8; ri. XLI, Fig. 1). Among the true chimney-builders the holes
of C. diogenes are also rather simple, consisting often of a single shaft with a pocket
at the bottom (Pi. .\1J, llgs. 5 and 6). In C. monongalensis they are decidedly
more complex (PI. X Id, Fig. 2), and the highest degree of complexity is reached
in ('. carolinus (PI. XL, Fig. 9).

The shape of the buri-ows of C. diogenes was first described by Girard (1852, p.
89), who called attention to their variable character. Tarr (1881, p. 127) has given
sketches of burrows of this species, and also observed their variability. Of C. caro-
liims, only the fact that it is a chimney-builder was known (Faxon, 1885«, p. 71).
The burrows of C. monongcdensis (as dubius) were described by \\'illiamson (1901, p.
12), and he emphasizes their complexity as compared with those of C. diogenes.

c. Construction of the burrows and of the chimneys.
Although the "chimneys" or mud-piles at the mouths of the burrows have
often been descrii)ed and their purpose discussed, (Girard, 1852; Tarr, 1854; Shu-
feldt, 1896; Harris, 1903), the manner in which the crawfish excavates the burrow
and piles up the mud in front of it had never been correctly observed. Abbott
(1885) describes how Mr. J. DeB. Abbott saw the crawfish (C. diogenes) engaged in
building its chimney, and states that it comes out of its hole " bearing on the back
of its right claw a ball of clay mud, wliirli by a dexterous tilt of the claw was
placed on the rim of the chimney." This description, as we shall presently see, is
apparently founded upon correct observation, but the observer witnessed only the
final act, and drew from it a wrong inference. The old ob.servation of Goodman
(1833, (1842), p. 293), that C. bartoni brings out of its hole an "armful of rubbish
and throws it over the side of his cell, and down the stream." should be quoted,
since, although referring to another species, it is pertinent and applies well to the
regular chimney-builders as regards the mode of cairying the mud.'""'

'■>Tlie way of carryinj; tlie niiul out of the holes seems to be identicnl in nil Imrrowiiig species. It has been ulaerved
in a similar form by Mr. W. S. Sutton in C. pilonus Hay, ns described by 1 larris ( 1900, p. 27->). That llie cniwlisli n.ws

420 MEMOIRS OF THE CARNEGIE MUSEUM

I have repeatedly observed the digging and the renio\'al of the dirt out of the
burrow. Of course it is impossil:)le to see tlie digging going on in the field inside of
the l;)urrow, and consequently this was observed in the laborator3^ in the case of speci-
mens of G. diogenes and moncntgaknsis kept in captivity in large glass jars partly filled
with clay and water. It is not difficult at all to see them at work, and after they have
been brought into the laboratory the specimens begin to work within a short time,
digging out the mud, carrying it upward and plastei-ing it all over the walls of the
jar. After some time (days or weeks), their activity lessens, and not much digging
is done, producing the impression that the}' have become discouraged in the effort
to construct something similar to the burrows in the field.

In digging the chehe of the first pereiopods are used. The fingers are slightly
spread out, so that they are al)0ut parallel, thus acting as forks for digging. They
are pushed vertically down into the mud on both sides at the same time, and a
lump of mud is thus loosened and lifted upward toward the ventral face of the
body. In lifting the chelipeds are bent toward the body (the region of the mouth),
and finally the ball of mud is appressed to the anterior part of the body and held
in position by the chelas. Very likely also the third maxillipeds take hold of it,
but it was impossible to ascertain this. In this position, as Goodman expres.ses it,
carrying an "armful " of dirt (or rather twoarmfuls), the crawfish walks slowly and
deliberately to the mouth of the hole. I have repeatedly observed it coming out in
nature.'' It advances to the top of the chimney and deposits the mud pellet upon
the rim, finally jjushing it into the proper position with the upper (outer) surface
of the claws. This latter act ajiparently was seen b}' Mr. J. DeP). Abl)Ott; but
according to my experience the mud is not Ijrought up upon the back of the claw,
but held, as described above, between the folded claws and the anterior part of
the body.

After luivinc; Ijeen disturl)ed in the field, the crawfishes often begin to woi'k again
within a short time, and it is chiefiy on such occasions that I have seem them at
work, with the excepti(jn t>f one case, when I saw a large male of C. dhxiciiex at work
on the evening of Aj)i-il .30, 1905, (Hunday), in Nine-]\Iile Run, Pittsburgli. TIk-

the " lateral tail-fins and telsoii " in any way. as suspected by .Sluifeldt ( 189(5), in the sealing up of the orilice of the
burrow, is hardly possible.

" The following particular instances maybe mentioned: C. baiinni in a spring near Burgettstown, Washington
County, Aug. 4, 1904 ; C. cnroliiius at Indian Creek, Fayette County, July 11, 19i)4 ; at Ohiopyle, Fayette County,
July 12, 1904 ; at Myersdale, -Somerset County, August 11, 1904 ; C. uKinniigdliiisis in Fern Hollow, Pittsburgh, May 6,
1901 ; at Edgewood Park, Allegheny County, May 9 and 31, 1004 ; April '21, 190,5 ; Mon.ica, Beaver County, June 150,
1904 ; at Cheat Haven, Fayette County, September 6, 1904 ; at Cameron, Marshall County, W. Va., May 1, 190.") ; at
Morgantown, W. V., May 16, 190.5 ; C. diogenes at Dunbar, Fayette County, September 7, 1904 ; in Nine-Mile Run,
Pittsburgh, April 30, 1905.

ORTMANN: THE CRAWFISHES OF THE STATE OF PENN.SYI.VAXIA 421

usual tiinc for working seems to be at night, and 1 have repeatedly observed that
holes and chimneys disturbed or destroyed on one day exhibited signs of recent
action on the following day. 'i'lic ci-a\vfishes also seem to work occasionally on
rainy or cloudy days; at all events, on such days it is easier to induce them to come
to the mouth of the hole.

As to the purpose of the •' chinuieys," different opinions have been expressed.
Abbott { 1 884) believes that the cliimneys are designed, and that the crawfisli intends
to build j\ist such struc-tures, that is to say, rather regular subconical mud towers.
He maintains this against Tarr's view (1884, p. 127), that the cliimneys are not a
necessary part of the burrows, and that they simply are the result of the digging.
Subsequent writers have rather inclined towards Tarr's idea, for instance Shufeldt
(1890, p. 80), who says that it is easier for tlie crawti.sh to build a chimney than to
carry the mud away from the hole, and that "it is the most convenient and safest
way to get rid of the pellets, besides being the least troublesome, and the method by
which they are the least likely to roll back into the burrow." Harris (1903, p. 605)
thinks that the chimneys very likely are only " the result of the easiest method of
disposing of the material i-emoved in excavating the burrow."

I must indorse the latter opinicm, and for the following reasons. Regular chim-
neys, although claimed by Harris (/. r.) to be "usually" present and well Iniilt,
are l)y no means so frequent as believed by most authors. Of coui-se they are
abundant in each colony of chimney-builders, and attract the attention of the
observer. However, according to my experience well built chinmeys are rather
scarce compared with the total numl)er of holes existing in a particular locality. In
the majority of cases only more or less irregular and shapeless mud-piles are found
at the mouths of the holes, and it is only under certain Aivorable conditions that tliey
assume the .shape of "chimneys."" Tbe.se conditions occur when the upper part of
the hole is more or less vertical (see PI. .\ b. Fig. 9 at .1 ; IM. .\l.i, I'ig. 2 at C; Fig.s.
7 and 8), so that there is opportunity for the crawfish, in bringing uj. the pellets of
mud. to deposit tiiem rather uniforiidy all around the rim of tiie chinuiey. Sup-
posing that it is always the lowest part of the rim at which additional pellets are
dei)osite(l, which is altogether a very likely supposition, if the crawfish wants t«i get
rid of the pellets as quickly as possible, the chimney must grow regularly, if. how-
ever, the mouth of the burrow opens in a slanting direction or horizontally, more or
less one-sided mud-piles will We tlie result. (See I'l. .\l.l, l"ig. 2 at .1 : Figs. :; and
4). iMiilher, iiincli (lepeiKJs on the character of the material brought up. If it is
fresh clay (not disturbed before), as will generally be the case when the crawfish is
digging out a new hole, the pellets will be firmer, stick better to the rim of tlie chim-

422 MEMOIRS OF THE CARNEGIE MU8EUM

ney, and will remain in position, thus favoring the construction of a "well-built"
chimney. On the other hand, when the mud is very soft, chiefly so when the craw-
fish is not digging new holes, but only cleaning out the old ones, the pellets are not
firm, and the more liquid mud will flow down the outside of the chimney and ren-
der it lower and l)roader and, consequently, less " well-built." This latter fact also
explains why young specimens often con.struet the neatest and most elaborate chim-
neys ( Al>bott). Young specimens, when they begin to work, bring out undisturbed,
firm, and sticky clay, and tlie pellets are more likely to remain where they are
placed on the rim of the chimney, which thus becomes very i-egular. Old speci-
mens, on the contrary, live in holes which are ^practically finished, and when they
work it is rather a process of " housecleaning " than of " housebuilding." The mud
removed is more li([uid and less stick}', and thus the chinnieN'S are shapeless and
irregular.

Very often the ojDening of the chimne}' is found closed. Abbott believes that
the closing is merely the result of the accidental falling in of tlie rim. This may
indeed happen, but in other cases it is plain that the crawfish closes the aperture
intentionally, and (lirard (1852) regarded this as the completion of the work of
chimney-building. Sbufeldt and Harris likewise believe that the crawfish itself
seals up the burrow. This is my own opinion, and with Girard I think that the
sealing up is the final act characterizing the completion of the burrow. Sealed
burrows are very often found (see PI. XL, Fig. 9; PL XLI, Figs. 2, 3, 4), chiefly in
summer and fall, and it is in many cases evident, by the material used (see PL
XLI, Fig. 6) that the shutting up was done by the crawfish by clrpositing ])ellets
in the orifice. Often the "stopper" is not at the orifice itself, but a certain distance
(5 to G inches) below. In fall the stopper is made rather substantially and fills the
upper end of the hole for a distance of ('> to 10 inches (see PL XL, Fig. 9// at I>), and
such a filling cannot be accounted for by accidental falling in.

]n my opinion the construction of the hole is the chief aim for which the craw-
fish works. For the removal of the clay and dirt an opening on the surface is
needed ; but wben the burrow is completed this opening is shut up again, and the
crawfish is content to remain inside, possibly for weeks or even months. This
affords protection for the crawfish and its young from enemies (snakes). Females
with eggs or young are almost always found in closi'd boles. It also affords neces-
sary quiet and seclusion during the moulting ])rocess (soft shells are generally found
in closed holes). It furthermore protects the hole from the disturbing influences
of rain and frost. Of C(jui-se it would not be advantageous to have the hole perma-
nently sealed, since the crawfish wants to get f)ut now and then (for mating, for

OliTMANN: THE CRAWFISHKS OF THE STATE OF PENNSYLVANIA 423

food), but this is necessary only at long intervals (even for food it is not absolutely
imperative to go out frequently, see infra), and the stopper is easily removed.
huring winter a more effective stopper is provided liy tlie crawfish, and it remains
ftir three or four months shut up in its liole.

The chief activity in ciiimney-building is in spring."" l>uring winter frost de-
stroys or damages the upper parts of the hole, and the rel)uilding necessitates a good
deal of work, and large mud-piles are accumulated in con.sequence (4 to 12 inches
high, 12 to 18 inches in diameter). But after the hole has been restored to a .satis-
factory condition work ceases, and in summer not much fresli mud is brought out.
Occasionally new chimneys are seen in summer, and the activity may be resumed
at any time if necessary. Besides young specimens remain active all through the
summer. In <'. diogenes, as we shall see, it is chiefly in midsummer that the
young l)egin to build their own holes. In the other species this may take place at
any time from spring to fall, and thus the new and often very regular chimneys of
small specimens may be seen at any time during tlie warm season.

( ienend activity again begins with older specimens late in the fall, and this has
a very interesting cause, and my attention was called to it Ijy Mr. V. K. Kdl}' of
rittsburgh, but I have confirmed it by subsequent observations of my own. It is
evident that the deepest parts of the holes are occupied and used by the crawfishes
only in winter; these parts go down to about three feet, and thus are entirely out
of reach of the fro.st. In sunnner these parts are abandoned and tlie crawfish in-
habits only the upper parts of its burrow. In digging for crawfish in summer I often
followed the main hole to a considerable depth, finally discovering that this hole
was filled with soft ooze and mud, and that no crawfish was in this part; further
careful investigation generally revealed a side branch at a higher level, which was
clear of mud, and here the crawfish was captured. In tiic fall the deeper, aban-
doned part of the hole (see PI. XLl, Fig. 7 at c), which fills up during the sunnner
with dirt, forming :it the bottom of the hole asoft. pulpy nuis.s, is reclaimed by the
crawfish in order to go deeper down out of reach of frost ; the nuid is consequently
removed, an<l the necessity of cleaning out these deeper pnrts of the hole is the
cause of the renewed activity in the autumn (PI. .\LI, Fig. 7). Before Mr. Kelly
communicated to me his discovery of this fact I had not paid attention to it. but
was able to verify it in the summer and fall of lUUo. The fall activity tnkes place

"Young specimens begin first, as soon as the fro.st is out of the ground. New cliinineys of C. ilhgrmf were ecen
on March 23, 190.5, in Nine-Mile Kun, and the activity wasgeneial on April G, 190.'), ( K'cnfrew). Tlie limt signs of new
chimneys of C. iminnngnlni^is were seen at Edgewood I'ark on March 18, l!)(l."i (frost only partly out of the ground) ; the
activity was general on March ;51, (Colliers, W. Va.), and April I (Edgwood I'ark).

424 MEMOIRS OF THE CARNEGIE MUSEUM

in the month of Novemher (in the neigliborh(M)d of Pittsburgh), after tlie iirst kill-
ing frosts.'*^

It is evident froni the foregoing observations and considerations that the '" chim-
neys " are not necessary parts of the burrows. They are simply the result of the
work of the crawfish, and only represent the material removed from the holes,
which must be carried somewhere, and is most conveniently disposed of right at
and around the mouth of the hole. The regular shape of the chimneys is simply
due to the way the crawfish has to work under certain conditions, and to the phys-
ical properties of the clay.

Nevertheless there are certain advantages connected with the shape of the chim-
neys, which, however, are by no means always present, and, in my opinion, are not
originally intended. The uppermost part of the hole generally has the tendency
to be more or less v'ertical ; an addition of 4 to \2 inches adds so much to the
length of the vertical canal, and the crawfish, when sitting at or near the mouth, is
able to suddenly drop down to escape enemies, which, as [ have repeatedly
observed, it actually does. Thus a considerable length of the vertical part is
decidedly advantageous, giving the crawfish a chance to get more suddenly and
effectually out of reach of danger.

Another effect of the nuid-pile is noticed when the hole o^jcns horizontally on
sloping ground (Ijanks of ditches). Here the mud-pile generally is semicircular,
convex toward the ditch, concave toward the mouth of the hole, and thus serves to
keep the water at a uniform level in the hole (PI. XLT, Figs. 2 and 3), for generally
in such cases the hole has spring-water flowing out of it. This may be advantage-
ous under certain conditions, since I have often fcHind that liy removing a pile of
nu)d of this character I was able to drain off the water from a considerable part of
the hole, thus making it distinctly uncomfortable for the crawfi.sh, as is evidenced
by the fact that it often came out of the hole, as if to investigate the cause of the
sudden disappearance of the water.

^'In 1905 it began rather late. On November 8, in Fern [follow ami Nine-Mile Run, no fresli cbinmevs were
seen on the golf links, where C. dliigeiiea is abundant. On November 22 fresh mud piles were numerons at the ident-
ical locality, several sharp frosts having occurred in the meantime. The same dates and the same facts were ascertained
tor C. mnnongalensis in Fern Hollow. Mr. Kelly's observations were made November 14 and 15, 19(14, but in 1904 I
noticed fall activity as early as November 5 (Nine-Mile Run, ('. dingoux). (See PI. XLI, Fig. 5.)

OKTMANN: THE CRAWFISHES OF THE STATE OF PENNSYIA'AN'IA 425

B. Geogkai'hical Distribution.

(Plates XLII and XLIII.)

1. Camharus lirao.fus.

a. Summarji of Facts (see above, pp. 35G-358).

This species belongs to the rivers, ponds, and canals of the lowlands of the At-
lantic (yoastal Plain and tlie Piedmont region *" in the states of New Jersey, Penn-
sylvania, Maryland, District of ("olumbia, and Virginia. It has not been reported
from the State of Delaware, but must certainly occur there also.

In Pennsylvania it extends up the rivers to a certain distance and in the Sus-
quehanna iviver enters the Alleghany Mountain region. In Maryland it goes up
i\w i'otonuic River, reaching the eastern extremity of West Virginia, thus also en-
ti'i-jng tlie Alleghany Mountain region.

Thus it is found in Pennsylvania in the drainages of the Delaware, Susque-
hanna and Potomac Rivers ; but it decidedly prefers the region of the lower Dela-
ware, from the bend of the river at Trenton downward. Here it is exceedingly
abundant, as also in the lower and quieter parts of the Schuylkill River at Philadel-
phia. It goes up the Delaware and Schuylkill, and is found in their tributaries
within tlie Piedmont region, but here it is by no means as abundant as in the Dela-
ware. It seems to be absent in the great Alleghany Valley between the Susque-
hainia and the Delaware, but reaches the foot of the Blue Mountain between the
Su.squehanna and Potomac, occupying the Cumberland \^illey (part of the great
Alleghan}' Valley), and in the Susquehanna and Juniata it a^scends even further,
far into the Alleghany Mountains (Center and Bedford Counties).

h. OrUi'iii of the distribution of C. limosus.

III. J'cii.nsi/lraitia.
ill the Delaware Kiver al)ove Trenton this species goes up as far as Nrw IIo|)e
in lUuks ('i)unty; but is very rare there, (only one specimen was secured liy tiie
writer after a prolonged search), and it seems that it does not go far lieyond tliis
point, if at all. Professor A. E. Davison informs me that it is not found near
Easton, North^impton County, about ten to lifteen miles from the Blue Mountain,
and I was unable to find it in the Little Lehigh Creek lu'ar Emaus, Lehigh Coinity.

•"As to tlie division of Pennsylvania into Cnastnl Plain, Pinlmnnl Plttlrnii, GrrnI Allfi/hnny f llry. ilhi/hnnii .l/.m..-
(dins nn<l Alleghany I'laliaii, see Davis, I8S9, p. I><7, an<l IIolli«t(T, IOm), j, |o, niiip. Fit; I • lUn |'.iw,-ll l-(ii'. j.
13ei seq. nncl map, and Willis. lU9ii, p. I(i9.

426 MEMOIRS OF THE CARNEGIE MUSEUM

Mr. W. Ti. ]Mc('onnell mentions (in his n(;tes) the absence of crawfish in the Dela-
ware at Porthmd, Northanijiton County.

It is found, liowever, in small tributaries of the Delaware in the southeastern
half of Bucks County (Neshaminy Creek). In the Schuylkill River it goes up to
Reading (Girard and also McConnell), and slightly beyond (Maiden ( 'reek) in ]^)erks
( 'ounty, but I have not been able to find it in the Schuylkill, where it comes out of
the Blue Mountain, (Shoemakersville). it has been reported from Brand3'wine
Creek in ( 'h ester County.

It is known from a number of places in the drainage of the Sus(),uehanna, Init
they are ail in the region of the Gi'eat Alleghany Valley or the Alleghany ]\Ioun-
tains. I was unable to find it in the Susquehanna in Lancaster and York Coun-
ties, (Pequea and Yoi'k Furnace), and I do not tiiink that it is present there on
account of the roughness of the rivei', which tlows over a I'ock}' bed in a channel
cut deep into strata, cliiefly of the archaic age, belonging to the Piedmont Plateau,
from York Haven to the Maryland state-line and beyond. Such conditions are de-
cidedly unfavorable for this species, and it is rather strange that it should be found
at all above this rough part of the Susquehanna, which is about thirty to forty
miles long. I think that this species immigrated into tliese parts in very recent
times by way of the Susquehanna and Pennsylvania canals, which closely followed
the river from its mouth in Maryland to the New York state-line and the Juniata
up to HoUidaysburg, and connected it with the Schuylkill. These canals were
maintained and in use a long time, beginning as early as 1834, were abandoned
about 1890,^' and at present only remnants of them are seen. C. l!tno.'<iiH is often
found in canals. First reported by Faxon from near ("uniberland, Maryland, I
have found it in considcralile numbers in the Sciiuylkill and Delaware and Uaritan
( 'anals. It is quite possible that the Susquehanna and Pennsylvania ( anals afforded
this species the means of reaching the Susquehanna River in the region of the < ireat
Alleghany \'^alley south of Ilarrisburg. Its further distribution up stream is then
not strange, after the rough portion of the lower vSusquelianna had been overcome,
or avoide<l.

The same may be true of the Schuylkill Uivei-. Although certainly originally
present in the lower ])ai-t, it was the Schuylkill canal (once connected with the Penn-
sylvania, canal) which possibly alfoi'dcd an o])])ortunity for '' '. IInio^^ks to go up the
river as far as it does now, since the Schuylkill above Philadelphia is rather rough.

" The maiu line of the canal was completed in 18:54, the Susijnehanna Canal from Columbia to Havre cle (iiace in
1840 ; see Jenkins, 1903, jip. 27.5, 277, 2S2 and Klein, 1900, p. LXXIX ; see also Hoyt & Anderson, 1905, p. 24. In
the latter paper line views of the scenery of the lower Susquehanna are published (PI. 1, B, PI. 8), which couvey a good
idea of the roughness of the water of the liver.

ORTMANN : THK CUAWFISHES OF THE STATK OF PENNSYLVANIA 427

Similiir conditions sooni to have played a part in tlie distribution of this species
in tlie Potomac River. It lias been reported from an old canal (Chesapeake and
Ohio) four miles south of Cumberland, and I have found it in the Potomac at
Cherry Run, West V^irginia. and at South Cumberland. At both places it was scarce,
and I am much inclined to Indicve that in this region (western Maryland and east-
ern West \'irginia) it got into the river from the canal. Originally its distribution
in Maryland was very likely similar to that in Pennsylvania, belonging only to the
Coastal Plain and the, Piedmont Plateau. ^-

Of the tributaries of the Potomac in southern I'ennsylvania those which empty
into the Potomac east of the Alleghai^y Mountain region also possess this species.
It lias ix'en found in the di'ainage of the Monocacy River at ( Jetty sburg, Adams
County, and that of the Conococheague-Creek in Franklin County, the latter local-
ity again belonging to the ( Jreat Alleghany \'alley. Further west, within the Alle-
ghany Mountains, it seems to be absent. I did not fnid it in l>ig Cove Creek and
Tonoloway Creek, Fulton County, and it is not in the collections made Ijy Mr. 11.
A. Pilsbry for the Philadelphia Academy in Sideling and Town (Jreeks, Wa.shington
and Alleghany Counties, Maryland. This supports the view that the presence of
this species in the Potomac as far up as Cumberland is due to the existence of the
canal. Above Cumberland, where the canal ends, C. limosus is positively absent in
the Potomac drainage in Penn.sylvania as well as in Maryland and in West ^'irginia.

Thus it seems that C Hmosus belongs oi-iginally only to the largei- rivei-s of the
southeastern section of our state, and that its real center for Pennsylvania is the
Delaware. It has .spread, however. u|)stream, and has approached the Alleghany
Mountain region, even entering the latter in the Su.squehanna River. This upstn-am
dispersal is apparently not everywhere due to natural migration. l>ut has lieeii
favored in recent times by canals. The present northwestern boundary, disregard-
ing the Susquehanna River, is marked by a line (.see PI. XLllI) running from New
Hope, Bucks County, to Maiden ('reek and Reading, Perks County, thence to P.ain-
bridge, Lancaster County, ( "arlisle, ( 'umberland ('ounty. and to Williamson, Frank-
lin < 'ounty. 'i'liis line, generally speaking, runs parallel to the I'lue Mijuntain, and
it is very likely that the differences in the physical features of the Piedmont Plateau
and the .Mleghany Mountains have something to do with the distributi<in of this
species, although the real cause cannot an}' longer be clearly .seen, the original con-
ditions being apparently obscured l>y several factors. l''or it shoultl not be forgotten
that the streams from the Susquehanna to tin- Pclaw.nc. i-suing through the Plue

*'Tlie Chesapeake and Ohio Canal forms a continuous watiTway from Wa.'<hinnlon to Cumberland, and was com-
pleted in 1850, see Hulbert, I'JOl, p. lUO, and map opposite p. SO.

428 MEMOIRS OF THE CAKNEGIE MUSEUM

Mountain from the Anthracite basin, are largel}^ charged with mine-water, and in
this section of the state (Berks and Bucks counties) we see that C. liviosus does not
so closely approach the Blue Mountain, wdiile in Cumberland and Franklin Coun-
ties, where the streams are clear, it goes to the very foot of the mountain.

Of course we cannot any longer ascertain what the original conditions were, and
thus it is hardly profitable to enter into an_v furtlier speculations. It is probable
that tlie original range of this species has been reduced t>n the one band by pollu-
tion of the streams, and has been extended on the other band by modern river im-
provements. How far this holds good in detail, remains doubU'ul.

General orhj'ni of tlt< ilidrihiil khi of <_'. hinosas.

Aside fi-om the more recent dispersal of this species just discussed, we are
prompted to incjuire how this species was able originally to reach the parts where
it is now found.

As the writer lias pointed out in a former paper ( l!)()5/>, p. 108, 111, 114, 127)
C. /r;»o.s«.s stands rather isolated geographically as well as morphologically. It
belongs to an ancient group of the sul)genus Fa.rouiuf<, probabl}' the most ancient,
which consists of five species. The other four species are entirely removed geograph-
ically from C lirnosiis, and are found in the central basin of the United States, in
Kentucky, Indiana, and Missouri, that is to say, about four hundred miles to the
west of the range of G. Irmosu.^, with the Appalachian System between them. We
have to deal here with a marked case of discontinuity of distribution in the /r//u«».s'-
gruup. Since, as has been shown by the writer in the paper referred to, we locate
the center of the suligenus Faxoii'm^ in the central ])art of the ^Mississippi ch-ainage,
G. Vnuoi^iix must have reached its i)resent liome by migration, and there are several
ways Ijy which it may have gone.

The most direct i-oute is acro.ss the Alleghany Mountains. AVe may suppose that
the //'/((o.svfi'-group oncte extended in the Ohio drainage uj)into western I*ennsylvania
and West Virginia, and that it was able by some means to cross the divide into the
Atlantic drainage. This does not appear impossible, inasmuch as in the mcjuntains
stream-piracy has taken place on a large scale during all ages (Davis, 1889). In
fact all of the larger rivers now running into the Atlantic have captured large tracts
originally l)elonging to the interior drainage. an<l the divide has Iteen continuously
shifted westward.

On the other hand, considering the ecological peculiarities of G. linw^Ks, this as-
sumption does iKjt appear very likely. The habit of living in larger streams in
rather quiet water would not favor a migration across the mountains, and if this

ORTMANN : THE CRAWFISHES OF THE STATE OF PENNSYLVANIA 429

ionn :u-Uiully came l)y the way indicated some traces of its former existence should
have been left in Pennsylvania. Maryland, or the \'irginias, chiefly since there was
no competition l>y any other species, river-forms being absent in the AUeghaiw
Mountain region. Thus the direct route across the mountains seems to be out of
the question, and this is further rendered probable liy another consideration.

C limosus being ancient, its migration eastward must have taken place at a re-
mote epoch, certainl}' at an earlier time than that of a group which is more advanced,
namely, the jJi'opinqniin-grouii. As we shall see beloAV, the latter existed already in
Preglacial times, and thus we are forced to place the origin of the limo.<ias-gnm\) at
least as far back as the Teiliary. During this time, however, ilie Ohio in ite pr(i<riit
form did not crixl. There was Spencer River,^'' in ^^'est Virginia and western Penn-
sylvania, and another river (Old Kanawha)^ in West Virginia and < >hio. running
northwaid to the Erigan Piver, wliich transversed the basin of Lake Erie.*'' And
further the present upper Susquehanna (North Branch) is apparently new. It must
have taken in Preglacial times a northward route toward the St. Lawi-ence l)asin,
possibh' also to the Erigan River (White, 1896, p. 376). All these rivers flowing
northward in Penns3'lvania and Ohio were different in character from what the
rivers of this region arc now. Their fall was slight, and they were rather sluggi.sh.
This is {)()sitively known of the Spencer River (or the Old ^h)nongahela), which
must liave been practically at base-level (White, 1896, p^. 377). If tliis was the case,
nothing is opposed to the assumption that C. Hmosuti (or its ancestral form) once was
an inhabitant of some of these rivers. Put then we see that its eastward migration
cannot have been in a direct route, but must have gone on in a roundabout way,
chiefly by the old Erigan River.

If the Erigan River was tributary to the ^Mississippi system, this is easy to
imagine. If it drained to the St. Lawrence Gulf, as Spencer believes, we must
assume an earlier crossing of the continental divide by this form, wherever this was
situated (Indiana?), and then again a crossing of the divide between the Erigan
River and the Atlantic coast drainage.

Be this as it may, we are forced to move the old range of the /i?«o.s-Hs-group to
the noith. into the Erigan River drainage, and this gives us the means of explain-
ing the discontinuous range of this group. If it were at one time present in an area
extending from Kentucky and Indiana through Michigan into Ontario, and if we
assume that it crossed over into the Atlantic drainage somewhere in northern Penn-

'» See Fosliny, 1890, p. 368 ; Leverett, 1902, p. 89.

«'Sce Wliite, 1896, p. .■{76 ; Leverett, 1902, p. 100 ; Tiglit, 190:i, ninp. Tlntc I, I'latra 16 iiiiil 17. (Tenys River.)

" Sec Spencer, 1881, map 2, aud 1891, p. 293.

V

430 MEMOIRS OF THE CARNEGIE MUSEUM

sylvania or New York, the advancing ice of the ({lacial Period must have entirely
covered a large part of this range. In the central parts, in Ohio and western Penn-
s^dvania, it was impossible for these forms to retreat southward, these parts being
occupied by another vigorous group of river-crawfishes, as we shall see Ijelow (/'/-o-
j>ivijtn(s-grtm\>), and onl_y in the east and west a chance to survive was left. The
eastern remnant is the present ('. limoi^ns, the western is the group of species found
now in southern Indiana and Kentucky.

How C. liviKtSKs reached the Atlantic ("oastal Plain from the Elrigan l)asin is very
hypothetical. One suggestion may be made. Not only does the North Branch of
the Sus(]uehanna seem to be a reversed I'iver, but the West Branch has captured
a large jiart of the original drainage of the Alleghany Plateau in Potter, ( 'ameron,
and ('learfield Counties. Davis (1889, p. 248) believes that this happened largely
in Pretertiary times, since he tliinlcs that the Alleghany Plateau belongs to the
Cretaceous peneplain. However, Campbell (1903, p. 280) has shown that there
are two old base levels in northern Pennsylvania, an older one (Cretaceous), iden-
tical with that of Davis, and a younger one (1,000 to 2,200 feet) corresponding to
the Harrisburg peneplain of Old Tertiary age. k>ince the headwaters of the West
Branch of the Susquehanna are carved into this second peneplain, it is probable
tliat during Tertiary times the stream-piracy of the Susquehanna was going on
rather vigorously. If we assume that ('. Jiniosus in Tertiary time existed in this
part of the Erigan River drainage, namely in tlie Old Upper and Middle Alleghany
Rivers,^" which did not belong to the Old Monongahela or Spencer River, it must
have been possible for it to get into the Susquehanna drainage in consequence of
this stream-piracy in Tertiai-y times. This, however, is a mere suggestion. There
is no other evidence for it but the bare fact tliat stream-piracy has gone on in this
region. I mention it here only to show that the crossing over of this species into
the Atlantic drainage is not altogether unthinkable.

After arriving in tlie coastal plain C. Umosus was cut off in the (dacial Period
from its allied forms in the west. But it survived, and in Postglacial times was
able to advance again. But the Postglacial dispersal cannot have amounted to
much, since the increasing roughness of the streams, caused by the Postglacial eleva-
tion of the country, was not favoi'al)le to a nortliward exjiansion. We do not know
the exact northern boundary of *". //mo.>--/(.y outside of our state. It is found in New
Jersey as far north as Morris ( 'ounty, yet we do not know whether it reaches Rari-
tan and New York 15ays, and the Hudson River. No positive record from New
York State is at hand (see De Kay, 18U, p. 23, and Pauhnier, 1905, p. 117).

"See : Carll, 1880, pp. 333 and 33«, map, PI. 2 ; Leverett, 1893, pp. 129 and 132 ; Tight, 1903, map, PI. 1.

ORTMANN: THE CRAWFISHES OF THE STATE OF PENNSYLVANIA 431

An alternative supposition might be entertained. C. limosms might have arrived
ill its present home coming from the south by way of the Atlantic Coastal Plain.
This, however, does not seem probable. First of all, the distribution of V. limos-us
does not extend southward beyond \'irginia, and even in \'ir.<,'inia it is known only
from a fijw localities. Southward no representative of this group is known on the
coastal plain, and, if C. limosus had come from the south, traces of this migration
might be expected. On the other hand, if it came from tbe nortli, as we here
assume, the fact that it did not spread beyond \^irginia may be accounted for by the
presence of another group of this genus, the subgenus (Aimharus (hlandingi-sectlon),
in the soutbern parts of the coastal plain, which, like C. Umosu.-^, prefei-s ponds and
sluggish streams. Indeed both species ( C. limosus and C. blandiugi) are found actually
associated at the same localities (by Faxon, 1885«, p. 88, at Trenton, New Jei-sey,
and by the writer in the Delaware and IJaritan Canal at Princeton, New Jei-sey),
but we must bear in mind that in New Jersey, and also in Maryland and Virginia,
C. hiaiidingi is an intruder, its chief domain being in the Carolinas.
The following are conclusions from the above considerations :
Cambarus Ihno>(US is an ancient species, characterized by morpiiological and
geographical isolation. The most closely related forms are found in Kentucky and
southern Indiana. An attempt to explain the presence of C. limosii.s at its present
location has to connect its range with that of these related species. A connection
by way of the Atlantic Coastal Plain southward is out of the question. Thus only
the connection across the Appalachian system remains. The fact that the rivere
just west of the mountains in western Penns3dvania are occupied by a more
advanced group of species (^;ro/m?r/f( »,v-group) of a subgenus which is cei^tainly of
Preglacial age, as we shall see below, leads us to the conclusion that the liruotuii-
group also must be not only Preglacial, but older than the propmquu,s-group. But
at that time there was no direct way from the lower Ohio, where its center of dis-
tribution was situated, into western Pennsylvania and across the mountains, the
Ohio having no existence as yet, and the general drainage in this region being to
the north. This leads us to assume a former more northern range of tbe limnxus-
group, extending into Preglacial Canada ; and this assumption furnishes an expla-
nation why it was possible for the Olacial Epoch to cut the range of the llmosiis-
group in two, leaving no representative of it in the region now drained by the
middle and upper Ohio. Carabunis liravsua is a Tcrtinri/ tijpc, and it reached its pres-
ent area coming from the west and by way of the north, being driven so^ith along the
Atlantic Coastal Plain by the advancing ice of the Glacial Periml. It .survived during
the Glacial Period in the region of the lower Delaware River and Chesajwah: Hay. while

432 MEMOIRS OF THE CARNEGIE MUSEUM

((// ihe rest of the fonner range of the group loas covered hg ice and ila reprcsentatices were
dedragcd, with the exception of n srnoJI remnant in the soiithivesteni- portion of the range,
in southern Indiana and Keiitncki/. outside of the glaciated area. The reason why
this group was destroyed in the glaciated area, and was not able to retreat
southward and to survive in the intervening parts ((^hio, Avestern Pennsylvania,
and West \"irginia), was that here the rivers were occupied hx another group of
the subgenus.

The above is a mere theory, and it I'eniains doubtful by which way ('. Vnnosus
reached the Atlantic Coastal Plain. The assumption that it was by way of the
Erigan River and the St. Lawrence l:)asin satisfactorily accounts for the facts, but
this is the only point directly in favor it. However, the .study of the distribution
of C. liiiiosus is not yet finished, since the actual boundaries of the distribution,
chiefl}' to the north and south, are not positively known. But this does not con-
cern us at present, since they are not situated in the State of Pennsylvania.

In C. JiiiKisus we have a species which survived during Glacial times in a part of
the Atlantic ("oastal Plain which is well to the north, not far from the southern edge
of the ice. Of course this forms a pai't of Adams' (1902, p. 121 ) .southeastern center
in its widest sense, lying at its northeastern extremity. Although surviving not far
from the edge of the ice, ('. lirnosus cannot be considered as belonging to ihe tuudral
l)iota (Adams, 10U5, p. 58), but it belongs very likely to the second wave (north-
eastern biota), with a slight suggestion of the third wave (southeastern biota) (/. c,
pp. 58 and 62). As Adams indicates, the first and second waves of Postglacial di.s-
persion had their glacial homes in very narrow belts parallel to the southern edge of
the ice, while the southeastern (and southwestern) biota covered in Glacial times
wide tracts of country. The second wave largely invaded the coniferous forest-belt
of ( 'anada, while the third wave was more stable and did not spread so far north-
ward. A\'ith regard to its geographical location during Glacial times, ('. limosus
should be classed with the norfJieaster)! hiota ; and with regard to its stability in Post-
glacial times, with the semtheastern. But we are to consider that a Postglacial north-
ward dispersion was rendered difficult in this case by the physiographical features
of the country. The coastal ])lain with its sluggish streams and stagnant ponds
disappears in northern New .Jersey, the uplands (Piedmont Plateau) reaching the
coast in the vicinity of New York Bay (see McGee, 1888, PI. 2) ; this did not offer
advantageous conditions for this species, and thus it remained within comparatively
narrow limits in a corner, into which it was pushed in Glacial time. C. limosus is a
Tertiar,g relic at the northern extremity of the coastal plain, which has not been able
to expand its area to any considerable degree in Postglacial times.

ORTMANX: THE CRAWFISHES OF THE STATE OF PENNSYLVANIA 433

2. Cambaru.s ijropiriquas, Cauibarus proptiKjuus suiihorni and Camhanis ohscurns.
a. Summarn of Facts. (See pp. 362-363; 368-369; 372-373.)

If we desire to arrive at a proper understanding of the distribution of C. propin-
quus, (J. prophupiiia mnhnrhi, and C oh.'icuruii, they must be discussed together.

The area occupied Ijy these three forms (see PI. XLII, Fig. 3) includes eastern
Iowa, southern Wisconsin, nortliern lUinois, Indiana. .Miohigan, ( )hio. northeastern
Kentucky, nortliern West N'irginia, western Pennsylvania, western New York, and
parts of Canada (Ontario and (Quebec). In the western and northern part of this
range C. ■pro]>iii(juus is found ; (J. prophxpiUii sanhoriii occupies the larger part of
Ohio and ])arts of Kentucky and West Virginia; while C. ohscurns has its chief
domain in western I'emisylvania, passing southward into Must \'irginia and iKjrth-
wartl into New York. Thus it is apparent that the three forms occupy different
sections of the general area of the group, propbupius being western (and nortliern),
sanbonii central, and (iliscurua eastei'n. As far as observations go all three formsare
rather jsharply .separated geographically, although they come into contact at the
edges of their ranges. This is especially true, as we have seen, in our state and the
adjacent portions of Ohio and West Virginia, while in western Ohio and in Indiana
nothing is known of the boundaries of the forms represented there.

In Pennsylvania only two of these forms are found (PI. XLII, Fig. 2). ('. propin-
quus is restricted to Lake Erie and its drainage ; C ohscta-us belongs to the Ohio sys-
tem, and is found everywhere in the western section of the state, in the Ohio, Mo-
nongahela, and .Mleghany Rivers and their tiilnitaries. The l)()undary toward the
east is formed liy the divide between the Alleghany and Susquehanna sy.steras, and
farther south generally b}' the ("hestnut Ridge (with exceptions to be discussed
below). Northward this species eros.ses over into the ( ienes.see drainage, and extends
into New York. It also crosses over into the Lake Erie drainage in Pennsylvania.

Along the western border of the state it pas.ses beyond the state line into Ohio,
the drainage belonging in the northern i)art to the Beaver River. Furthermore it
goes down the Ohio and is found in all creeks running from Pennsylvania through
the Panhandle of West Virginia as far .-^outh as I'ish ( 'ri'ek in ( ireeiir < 'ounty,
Pennsylvania, and Marshall ( '<ninty. West N'irginia. Fish ( 'reek falls into the ( )hio
a little below iSIouniisvillc West N'iruiiiia. an<l e()ntains only the typical form of
C. obscttrus.

Going further down the Ohio conditions suddenly change. In Fishing ( 'rock,
Wetzel County, West \'irginia, which empties into the Ohio near New Martinsville.
about thirteen miles below the mouth of Fish ( 'reek, (.'. priip'niipiiiK.idiihonii appears.
Put the form hei'e found is not typical. As we have seen above, it inclines some-

434 MEMOIKS OF THE CARNEGIE MUSEUM

wliat toward C. obscurm, and one individual lias l)een found wiiich represents
typical C. obscurus. In Middle Island ('reek near St. Mary's, Pleasants ('ounty.
West Virginia, which is al)out twenty-five miles further down the Ohio, the few
specimens collected seem to be typical C. propinquus sanJmrtii.

Thus it appears that C obscurus goes down the Ohio River to alxjut Mounds-
ville. West Virginia. All the tributaries of the Ohio in the Panhandle possess this
species, and very probably it will Ije found also in Ohicj on the opp<jsite side of the
river. But crossing over the divide between this part of the Ohio and the Muskin-
gum-Tuscarawas River in Ohio, we again find ('. projiiii<jnii.'< ><anJ>iinn in the drain-
age of the latter. The western boundary of (J. obscurus consequently is formed Ijy
the divide just mentioned, but this line crosses the Ohio River between Mounds-
ville and New Martinsville, West Virginia (PL XLII, Fig. 2, and PI. XLIII).

Further to the south in West Virginia in the drainage of the u})per Mononga-
hela this species has not been traced. It surely goes up the Monongahela bey(jnd
the southern l)Oundary line of Pennsylvania, Init how far has not been ascertained.

The fact that C. obscurns is found also in the Potomac drainage, in Wills Creek,
between Hyndman, Bedford ( 'uunty, Pennsylvania, and EUerslie, Alleghany County,
Maryland, deserves special menticjn, and will l)e eommenteil upon elsewhere.

b. Orujhi of the (li.sfriJnitlnv of ('. propivquus, propi nqiius sanhornu niid C (iJ)scnr(is.

In order to get a fair understanding of the distribution of these forms, we must
take notice of the Preglaeial physiography of the region in which they are found,
for, as we shall see below, we are led to believe that these forms ai'e of Preglaeial
age, and survived during the Glacial Period in the southern parts of the drainage
systems, which now constitute that of the ( Jhio.

First of all, we should bear in mind that at the end of the Tertiary Pei'iod before
the ice pressed down from the north, the Ohio River in its present form did not
exist. In the whole region, drained now by the middle and upper (jhio, the drain-
age was at that time not to the west, but to the north, and it was collected by a
river running in a northeasterly direction toward the present (iulf of St. Lawrence,
(the Erigan River or Ancient Cirand River). ^'

Disregarding some smaller streams, for instance the Old Middle and ( >ld U])pcr
Alleghany, which do not concern us here, three main rivers, tributaiy to the Erigan
River, have been traced with uKjre or less accuracy, and the evidence for their ex-
istence, although fragmentary, leaves no doubt as to the general correctness of the

■"This is tlie opinion of Spencer (1881 and 1894). Others believe that tliis river drained toward the Southwest,
into the Mississippi ; see (Jrabau, 1901, maps, p. 44 and 45 (Dundas River).

OKTMANN : THE CKAWFISHES OF THE STATE OF PENNSYLVANIA 435

main features of this drainage, wliieh dillers so strikingly from that which exists
to-day.

The easternmost of these rivers was the Spencer River, or Old Monongahela, or
Old Upper Ohio,^* which drained southwestern Pennsylvania, northern West Vir-
ginia, and a small part of eastern Ohio. West of it was the Old Kanawha River,
or Old Middle Ohio, or Teays River (Leverett, 19U2, p. 100, map, p. 101 ; Tight,
1903), which drained parts of West Virginia and Kentucky, and the larger part of
central Ohio. The old Muskingum-Tuscarawas River belonged to this drainage,
the Muskingum River not flowing southward, but westward and southwestward
from near Zanesville, Ohio, to ("ircleville, Ohio, thus joining the Old Kanawha
(Newark River; Tight, 1903, PI. 1).

The divide of the Old Kanawha to the westward was formed by the Cincinnati
uplift, and was situated according to Leverett (1902, p. 100) near Manchester, Ohio,
on the present Ohio River. P)eyond this divide we have the Linver Ohio system
(Leverett, p. 109). The Preglacial lines of discharge in this region are rather
obscure, but according to Leverett and Newsom (1902, p. 168, I'l. <)) it is probable
that a large part of the present system of streams was triltutar}' to the lower Ohio in
Preglacial times, but that a small number of them may have had a northward dis-
charge through the Great Miami basin in western Ohio (Leverett, p. IIG). There
are distinct indications of a northward drainage in the vicinity of ("inciimati (Cin-
cinnati River, Tight, I'JOo, PI. 1). This possibility is also admitted by Newsom
(1902, p. 181).

We may take it for a well established fact that in Preglacial times at least two
rivers existed in this region, the iSpencer and the (^)ld Kanawha, which did not
drain into the Ohio and Mississippi in a .southwestern direction, but Howed north-
ward into the Erigan basin. Westward there was very likely a third river ("(Hd
Miami") running in a similar direction; but in this region we arrive at the old
Preglacial divide between the Lower ( )hio and the Erigan Uivtr. It remains
doubtful whether the latter drained to thi' St. Lawivnce Oulf or to tiir Mi.-;.>i.<.-ippi
by the way of the |)resent Wabash.

Assuming the theory of the former existence of an Old Miami (or Cincinnati)
T\iver, we see that there are certain interesting relations of these three old rivers to
the present distribution of the three forms of (.'(intlxirn.'i under discu.ssion.

Ofcour.se, we must disregard those parts of the ranges of the.^e forms which lie

«*See above, p. 429. Descriptions are given by Fosbny. If^OO, Wliite, 1803, and I.everelt, 19(1*2, p 8^! (witb iniip
on p. 89). Additional evidence bas been furnished by Mice. l!1(i:!, p. :in2. Anolberuainc is rillsbiii^b IJiver /rijjlit,
1903, PI. 1).

430 MEMOIRS OF THE CARNEGIE JIUSEUM

in the formerly glaciated area, for these are due to Postglacial expansion. But
looking upon the localities south of the terminal moraine (PI. XLII, Fig. 3) we see
that only a few are known for C. pi'ojnnquus, and these are all in southern Indiana
(Prown, Monroe, and Green Counties),*' and belong very likely to the old Lower
Ohio drainage, hut in the region where it comes into, contact with the suj^posed Old
Miami River (or possibly some other river flowing north in the State of Indiana).
Since we have reason to believe (Orlmann, 19056, p. 114) that the center of ra<lia-
tion of the subgenus Faxoiiins, to which the propinquus-group belongs, is in the
centi-al basin formed by the thi'ee great rivers (Missouri, Mississippi, and C)hio), ('.
prop'hiqavs distinctly points toward this center, of which southern Indiana forms
part. This is the more interesting since we see that it is the most primitive species
of the jirojiiiiijtiux-gvou]) which most closely approaches the original center. In
Preglacial times ('. prujiliiquns belonged to the northeastern extremity of the old
Ohio drainage (Lower ( )hio), and in tliis region there apparently was a chance for
it to cmss over the continental divide into the Atlantic (St. fjawrence) drainage.
If however, the Erigan River drained to the Mississippi, the presence of this
species in the Lowej- (_)hio and in the lower part of the Erigan River is more easily
accounted fnv Ijy direct communication of the waters.

Taking up tlie distribution of ('. projiinqiins sanJxrrni, we observe that until
recently oidy one locality was known to the south of the di'ift, namely, the type
locality in Carter County, Kentucky, which is undoubtedly in the drainage of the
Old Kanawlia River. In addition, I have discovered a number of localities in
eastern Ohio (< 'arroll, Harrison, and Stark Counties), and in northern West Virginia,
wbich l)elong to the same drainage (Newark River and Marietta River, tributaries
of the ( )ld Kanawha), which are also outside of the glaciated area (at Canton,
Stark ( 'ounty, ( )hio, close to the edge of the drift).

The chorological facts about the disti-ilnition of ('. jiropinqtiv^ and C. jiroprnqiius
sanhorni are very meager, and not at all .satisfactory; but as far as our present
knowledge goes, all known localities of C. propiiKpnix sdiilmnii, outside of the drift,
are in the drainage of the Old Kanawha, while none of the known localities of ('.
propiiiqnu^ are in this drainage, but are situated to the west of it. Now, this
mutual relation between distribution and Preglacial drainage becomes more evident
when we look upon ('. oltsrnrn.'^, the distribution of which 1 have studied more
closely.

*'They are close to tlie southern etifie of tlie drift, ami it is a little doubtful wlietlier they are inside or outside of
it. Disregarding the Ulinoisan drift, they are surely outside of the Postillinoisan glaciation, as is also a loaility in
Franklin County, Ind.

ORTMANN : THE CRAWFISHES OF THK STATE OF PENNSYLVANIA 437

Leverett (1902, p. 89, Fig. 1) has given a map of the Old Monongahehi River,
which is reproduced on Plate XLII. Fig. 1, and alongside of it. Plate XLII. Fig. 2,
I give a map of tlio present distrihution of ('. ubscKnis. It is evident at a glance
that there is close correlation between ('. (Mairus and this old river. The most
important features are furnished 1)\- the western boundary. The divide between
the section of the Ohio which runs along the Panhandle of West \'irginia and the
Muskingum-Tuscarawas drainage is the old divide between the drainages of the
Spencer River and the Old Kanawha. This divide crosses the present C)hi(j just
above New Martinsville (see Leverett's map, p. 90, Fig. 2 : " proljable early di-
vide"). As I have found (p. 434) this old divide coincides with the present boundary
between C. obscurus and C. obscurus scinborni. It also is significant that it is not the
Tertiary (Preglacial) divide, whidi is located by Tight (1903, PI. 11) ju.st below New
Martinsville, nor the "later divide" of Leverett (/. c), but just the one which
existed at the beginning of the Glacial Period. We shall have to return to
this topic.

Thus it is clear, first, that the original separation of these two forms was brought
about Ijy the fact that they belonged to different river systems; second, that we
must assume, the Preglacial age of the jii'opinquus-group ; and third, that the distri-
bution of these crawfishes furnishes additional evidence for the correctness of the
view of the Old Monongahela and Old Kanawha, as held by Leverett (and otliei"s) ;
and with reference to these crawfishes it seems to me that the following theory is
rather well founded.

In Preglacial times, the propinquus-group, coming from the southwest {lower Ohio)
reached the Erigan River drainage (either dircctlg or bij crossing a divide), of which it
became characteristic.^ It entered, consequently, also the southern tributaries of this
river, and ojving to the fact that there were three main irilnUaries, this group developed
the tendency to split up into as many geographical forms. These were apparently the
conditions when the Glacial Period began.

The chief effect of the advancing ice was that the northern parts of the range of
this gi'oup were covered by ice. Only in the region of the headwaters of these
rivers, to the south of the edge of the ice, was there a chance to survive, anil sur-
vival here occurred. Both the Old Monongahela and the Old Kanawha were

'*' We have seen that a similar dispersion very likely took place in the case of the limu.iuanTOup. The latter beinj;
more primitive, we must assume that it formed a lirst aud earlier wave of immigration from the Lower Ohio into the
Eri(;an drainage, while the proyji'iijiiKs-group came later. This movement is still goinR on. There is evidence of a sob-
seqnent Postglacial wave (later than the Postglacial migration of C. pnipiiitiuiif) also sUrting from the Lower Ohio, and
represented by the nis^ciw-group, which again has all the morphological marks of a more recent type than the propin-
quus-group. But this is outside of the scope of the present paper.

438 MEMOIRS OF THE CARNEGIE MUSEUM

dammed up by the ice, and transfonued into lakes (Lake Monongaliela of White,
1896, and Lake Ohio, cf. Jillson, 1893. p. 19, and Map, PI. 5, with the necessary
restrictions), and this led to the I'esult that the colonies uf crawfishes bel«)n;L;in,i;' to
the southern (upper) parts of these rivers became sharply sejiarated fi-Din each otiier,
and I think that the foidmcji toivard llie formation of three species {('. jtritjiiinpnis, C.
sanhonn, C obscurus) is (Jirecth/ (hie to ilris process amJ Id iiIii/-'<i<>(/roi)]uc(il comlifiovs
prevailinij in tlie earlier part of the (jlacial Period (Kaiisan or Prekansai}, cf. Hice,
1903, p. 300).

Finally these lakes were connected and drained off toward the southwest, thus
forming the present Ohio River (Postkansan, but liefore the Wisconsin stage, cf.
Hice, 1903, p. 29rl); the areas of the three forms of crawfishes were reunited, but
the different parts of the new Ohio drainage are occupied by diffei'ent forms of the
projiiiKpius-gixmp, remaining in their original areas; the ui)per Ohio is character-
ized by ('. oJ>scnras. the middle Ohio by C propinqaus sanhoriii, and the lower Ohio
by ('. propineprus.

]'>ut additional changes took place in Postglacial times. According to the pres-
ent distril)Ution these must have been greatest in the case of C. propimpeus.
Almo.st the entire range of this form lies within the ijlaciated area, and thus it is
beyond question that its present distribution is largely due to the Postglacial migra-
tion northward and northeastward.'' This migration possibly began at an earlier
date than in the case of the other two forms. We know that in southern Indiana
and southwestern Ohio an early i-etreat of the southern border of the ice took place,
as is indicated by the presence of lllinoisan drift soutli of the early Wisconsin border
(cf. Leverett, 1902, PL 2 and PI. 11). Tliere also was considerable recession of the
ice of the Maumee-Miami glacial lobe in the earlier and later Wisconsin stage, while
in central and eastern Ohio and western Pennsylvania (Scioto glacial lobe and
(irant River glacial lobe) only in the later Wisconsin stage did recession take place
[cf. Leverett, ibid., and PI. 13 and PI. 15). Toward the end of the later Wisconsin
stage large lakes began to form in front of the receding ice, and this happened first
in the western part of this region. Tiie first lake thus formed was Lake Maumee
(Leverett, p. 710 tf., PI. 20 and 21). which had an outlet toward the west and south-
west (Fort Wayne outlet; see also Grabau, 1901, p. 58). Lake Maumee was situ-
ated in northwestern Ohio, in the present Huron-Frie basin, and thus we see that
the latter was opened first in its western part tcj an immigration from the southwest

^' A loss of territory must liave occurred in the sontli, C. propinqints losing ground in competition with C. rusticus
which was pushing on from the south. This matter does not belong to our present investigation, but attention should
be called to it.

ORTMANN : THE CRAWFISHES OF THE STATE OF PENNSYLVANIA 439

(Indiana) at a tin)e when tliis basin was entirely covered by ice further east, thus
being closed more or less to an immigration from the central parts of Ohio (drain-
age of middle Ohio), and being closed entirely to an immigration from eastern
Ohio and western Pennsylvania (drainage of upper Ohio).

This explains why C. jrropinquus, which survived in southern Indiana, had the
first chance to spread northward and t(j enter tlie future Hunjn-Erie basin by way
of Lake Maumee. The subsequent stages of this lake (Lake W'iiittlesey, Lake Warren,
etc.), are all direct continuations in time of Lake Maumee, and so it is not astonish-
ing that C. irropinqxnLs, after the final establishment of the St. Lawrence drainage,*-'
is found all over this region, not only in the Lake Huron and Lake J^rie basins, but
also farther down, in Lake Ontario and the Lower St. Lawrence drainage. In the
occupation of this whole region C. propinqmis was not interfered with by the other
forms, since no opportunity was given to C. propinquus sanhorni and C. obscums, to
enter the Erie basin, the drainages of the middle and upper Ohio remaining perma-
nently changed to the southwest, away from Lake Maumee, a condition which ob-
tains, with very slight changes, up to the present time.

However, C. propmqmi.s sanhorni as well as C. (Mcanis, have entered the Lake
Erie drainage. With regard to the first, it maybe sufficient to state that it is found
in Lorain County, Ohio, in rivers and creeks running into the lake, and this is ap-
parently due to a comparatively recent immigration under similar conditions as in
the case of ('. oJisciirns in Pennsylvania. 11 if latter species has been discovered by
the writer in Crawford and Erie Counties. Pa., in streams fiowing to Lake Erie,
associated with the Lake Erie form, C. j^rojnnquv.-^. Thus C. obscurns must have
crossed the divide between the upper Beaver (Shenango) River ami Alleghany
River (French Creek) on the one side, and Lake Erie (Conneaut and Elk Creeks) on
the other, and the question is by what means this was accomphshed.

It is only natural that C. obxcurus, surviving during Glacial times in soutli-
wcstern Pennsylvania and West Virginia, migratetl up the drainage of the upper
Ohio, chiefly the P.eaver and AUegiiany Rivers, in Postglacial times, for after
the end of the Glacial Period this system formed a unit", and no .serious l>arriers
to the dispersal were, or ai-e, present. Thus it was easy for this species to go up

" The cliange of the westward ilraiiiiifje to an castwarii took place toward the cud of tin' Olncial Perio«l, as rooii m
the ice recede<l far enough to nncover Ijike Ontario (l-ake Irmiuois), thii» permitting tlic water to dr .in olT iliroiijili tlie
Moliawk, and hiter throuKh the St. Lawrence. This was ncconipanied prolmhly l>y a depression of the land in the
Northeast, enlniiimtiiiK in the marine invn.sion of thcSt I^iwrencc valley (Clmmplninmihmcrgence). (SceGmlmn, 1»»1,

p. 59 et srq. )

"As to the formation of the present Alleghany out of the former Lower, Middle, and Ipper Alleghany, see Lev.

erett, 1902, p. V29 it siq.

440 MEMOIRS OF THE CARNEGIE MUSEUM

toward the head-waters of these rivers and to closely aiiproaeh the divide toward
Lake Erie.'^

This would favor a direct crossing of the divide h}' actual migration over land,
and indeed the river-species are al)le to survive when out of the water for a consid-
erable time under certain circumstances, as 1 have ascertained by experiments.
During hot and dry weather it is hardly possible to keep them alive for more than
an hour or two ; but in cool, cloudy, and damp weathei- I have found that speci-
mens suspended on a string on an open veranda"" were not dead after seven hours,
and restored to water, recovered entirely. This might at least render a
migration over land possible, but I do not think that it actually takes place,
since it has never been observed, either by others or by myself, that C uh-
scurus, or any other species classed ecologically with the river-species, leaves
the water voluntarily. On the other hand it is possible that C. ohscwrus may
undergo a passive transport from one drainage to the other, as for instance by Ijirds.
However, I do not believe that the crossing of the divide toward Lake Erie is due
to the latter cause. It seems to me highly improbalile, not that birds should be
able to carry crawfishes for a long distance, but that it should happen that a bird
should take up a crawfish in one stream, carrying it to another safe and sound, and
arop it there without hurting it. Birds do take crawfishes "^ and sometimes carry
them short distances, but this always results in serious injury, even if the specimen
is not immediately eaten. Thus, even though we may admit that crawfishes might
be transported by birds without being injured, such cases must necessarily be
extremely rare, and do not happen often enough to efiect the establishment of a
species in a drainage system from which it was originally absent.

There are other considerations which make the assumption of passive transfer
improbable in our case. Toward the east ('. nbscurus is (with exceptions to be dis-
cussed below) rigidly restricted to the Ohio drainage, and nowhere crosses into that

^* At Linesville, Crawford County, I found tliis species in the very headwaters, almost in the springs running into
Shenango River just south of Summit, wliich is on the divide.

*'' Particulars of one of the experiments ( I liave made a series) are as follows : November 9, 1905. Cloudy day.
Mean temperature : 31° F. Light breeze from West-South- West, and light snow in afternoon. Specimens of C ohscunis
suspended on strings on veranda with southern exposure. Beginning of experiment 9 a. ni. One specimen taken in at
2 p. ni., another taken in at 4 p. m , and put into water. Both alive and vigorous ne.\t morning, and were kept alive
till December 18, when they were thrown into alcohol.

In midsummer, on hot days, I often observed that the vitality of C. obscunts becomes very low after they are only a
short time out of water. They may die within an hour, without having been subject to any other injury than that
caused by the removal from the water.

5'' Mr. W. E C. Todd informs me that remnants of crawfish are quite usual in the nest of the kingfisher. 1 have
seen, in the collection of the Department of Agriculture, Harrisburg, a specimen of C. barloni, taken from the stomach of
a kingfisher.

OKTMANN : THE CKAWFISHES OF THE STATE OF PENNSYLVANIA. 441

of the Susqueliiuiiia. If traii-sport were at all jnubaltle we sliould expect to fiml
that it liad taken place here, as well as in the region of Lake Erie.

Further, and this is the most important olyection to the transport theory, while
C. obscurus has invaded the Lake drainage, not only in Pennsylvania, hut also in
New York (Genessee River), in no case has the opposite taken place namely, that
C. propinquus has invaded the Ohio drainage. If the cro.«sing of the divide were
due to passive transport, the same cause should have acted in hotli directions; but
C propinquvs is entirely absent from the Ohio system.

The latter objection holds good also with reference tcj another assumption, that

C. obscurus may have crossed into the lake drainage by the aid of the old canal
which connected the Beaver River with Lake Erie (Erie extension of Beaver canal).
This canal (see Jenkins, 1903, p. 288, 289) was in i)art used as early as 1834, and
was completed in 1844 ; it was abandoned in 1871, and it cannot be denied that by
it C. obscurus might have been able to reach the Erie drainage. I would not liesi-
tate to accept this as correct if it were not for the fact that C. propinquus has not g(jne
in the opposite direction.'"" Precisel}' in the region of this old canal my collections
are very complete, and are supplemented by those of others (Messrs. O. E. Jennings,

D. C Hughes, and W. R. McCouuell), so that I am positive about the absence of
C. j>ropinqims.

On the other hand, we have seen that the specimens of C obscurus from the
tributaries of the lake seem to approach more closely those of Beaver River than
those of French Oreek. This would be in favor of the canal-theory, the canal run-
ning from Newcastle by the way of Shenango River to Conneaut Creek (Jenkins,
/. c), while French Creek was not so closely connected with it (although there was
a "French Creek feeder"). The aljsence of C p/-o^>/?i7»«.5 in the lieaver drainage
may be due to the fact that in Erie County, the canal was not so closely connected
with the streams running to the lake, and that thus the lake species could not get
into the canal ; or else C. propinqutis being the weaker species of the two could not
make any headway against the more vigorous C. obscurus.

There remains another theory, namely, that the migration of C. obscurus into
Conneaut and Elk Creeks is due to stream-piracy. The latter has undoubtedly
taken place in this region in Postglacial times. The Postglacial divide between
Lake Erie and the Ohio was formed originally by moraines t)f the late Wisconsin
stage (Lake escarpment morainic system. See Leverett, 1902, PI. 18; also Carll.
1880, PI. 1) or by higher elevated parts of the non-morainic drift lying immediately

^ It should, however, he home in mind that the dischnrpe of tlie wnter from the cnnal %vaa downward toward the
lake and thus that migration might in that direction have heen easier than in the opposite. — Editor.

442 MEMOIRS OF THE CARNEGIE MUSEUM

in front of this morainic system. The fall of the creeks running northward to Lake
Erie from this divide is much more considerable than that of those running south-
ward, and thus it is clear that erosion on the northern slope must have been more
efficient than on the other side. The consequence is that the tributaries of Lake Erie,
at least some of them, have worked back through the original divide, and have cap-
tured parts of the original Postglacial drainage of the Ohio. This is most evident
(see PL XLIII) in the cases of Conneaut and Elk C'reeks, and it is just in these
creeks that I found C. obscurux associated with (.'. pnijiiiujuus/'' while in Walnut
Creek, which has apparently not entirely cut through the original divide, C. oh-
seurus is not found.

Thus it is possible that the presence of ('. ohscvrus in the Lake Erie drainage is
due to stream-piracy. Both species, ('. (ihscuruf! and j)roj)inquus, are associated here,
but it seems that they are antagonistic to each other to a certain degree. In the
tributaries of Conneaut Creek I found C. propinquvs exclusively, while (Jonneaut
Creek itself contained l)oth, but C. obscunts prevailed, and it appears as if the latter
had driven out the other species, which took refuge in the smaller tributai-ies.

We might expect to (jbtain S(Miie light upon the question, whether C. obscurns
reached the Lake Erie drainage in consequence of stream-piracy or by the help of
the canal, by the analogy offered in the Genessee drainage, but conditions seem to
have been not entirely identical here. The type locality of C. obscurvs (see PI.
XLII, Fig. 3) is the Genessee River at Rochester, Monroe County, New York, where
this species also is found associated with C. pro^nnquns. Mr. W. 1'. McConnell has
discovered C. obscurns in the upper Genessee drainage near Ulysses, Potter County,
Pennsylvania. The material consists of numerous males of the first and second
form and of females, and there is not the slightest question that this is the true C.
obscurus, no trace of C. propinquus being present here. How did this species get
from the Alleghany drainage into that of the Genessee ?

The drainage of the Genessee River lying entirely within the glaciated area, this
must have happened in Postglacial times. Fairchild (1896, p. 423) has shown that
during the recession of the ice the Genessee basin was occupied by a lake, which had
its outlets in different directions successively, draining either to the Susquehanna or
to the Ohio. He distinguishes ten stages, and the sixth was the last in which the
water flowed to the Susquehanna; in the seventh and eighth stages Genessee Lake
became connected with Lake \Varren, which drained to the west into the Missis-
sippi basin (but not into the upper Ohio), and finally the St. Lawrence drainage was

'■'The sources of Elk Creek are in a tamarack swaiDii, which also drains to the south, to French Creek, so that some
kind of a direct connection may be present. I have not visited this swamp.

ORTMANN : THE CRAWFISHES OF THE STATE OF PENNSYLVANIA 443

establislied. Thus we see that in the beginning Genessee Lake was connected
repeatedly with the upper Ohio (Alleghany River) drainage, l)Ut it is not probable
that C. ohsciirus immigrated at this time, for then it ought also to have reached the
Susquehanna drainage, since the lake discharged its water into the Susquehanna
(through the "Burns outlet'") subsequently to the last coiniectiitn (" Cului outlet ")
will) the Alleghany Kiver. (See Fairchild, 1896, map. PI. 19.)

After this a discharge toward the upper Ohio was never re-established. But we
know that stream-piracy has taken place in this region (headwatei-s of the Genessee),
and although in some cases the Alleghany River seems to have captured pails of
the Genessee drainage (Oil Creek has captured the head of Black ( 'reek ; see l^ev-
erett, 1902, p. 207). the opposite has positively also taken place, for instance, Knight
Creek and Van Campen Creek have captured, according to Fairchild, small lakes
that once discharged towards Oswayo Creek, a tributary of the Alleghany. This may
have happened after the sixth stage of Lake Genes.see, when there was no longer
an}' connection with the Susquehanna system, and would explain the presence of C
obf<ci(rn>> in the Genessee River and its absence in the Susquehanna.

The eastern l)Oundar3'of C. obsairus in Pennsylvania is formed, generally speak-
ing, l)y the divide between the Ohio drainage in the west and that of the Susque-
luunui an<I the Potomac in the east. This is most evident in the northern part of
this line, in Potter, McKean, Elk, Clearfield, Jefferson, and Indiana ( 'ounties. This
species goes up the Alleghany River probably into Potter County, for it has been
found not far awa}' from the county line at Larabee, McKean County. It has not
been found in the drainage of Clarion River in Elk and Jefferson Counties, V>ut this
is very likely due to the excessive pollution of this river. There is hardly a water-
course known to me in Pennsylvania which is in a worse condition than ( 'larion
River in Elk County. The wood-pulp mills at Johnsonburg. the tanneries at Ridg-
way, the chemical fact(jry at St. Mary's discharge refuse into it, ami Toby ( 'reek
adds sulphur water from the mines above Brockwayville (Jefferson County). Simi-
lar conditions prevail in Red Bank and Sandy Lick Creeks in Jetlei-son ( 'ounty. but
I have been able to ascertain the presence of this species near the head of Sandy
Lick Creek at Dubois, Clearfield County (about 10 miles from the divide).'" In
southern Jefferson County, ('. ohscurus is not present in Mahoning Creek at Punx-
sutawney (although C. barUnii was there), this creek being slightly polluted by mine-
waters; but I found it here in a pond connectetl with tlu- creek, in Indiana
County it is present in all creeks running to the Alleghany and ( 'onemaugh ( Little

"I found this species here on June IB. 190,5. Only two livinR specimens were taken, but nnnierous dead ones were
lying in the creek. Apparently some injurious substance had been quite recently introduced into the water.

444 MEMOIRS OF THE CARNEGIE MUSEUM

Mahoning Creek, (/rooked Creek, Two Tick, and Yellow ( 'reeks). Crossing over the
divide in this region into the drainage of the West Branch of the Susfjuehanna, no
trace of this species is found. I hunted for it in vain in Sinnamahoning Creek in
Cameron County, in the West Branch and its tributaries in ('learfield, Cambria,
and Indiana ( ounty (near ('berry Tree), and in ('learfield ( 'reekin ( "ambria County.

In this whole region (headwaters of the West Branch) stream-piracy has taken-
place on a large scale, the whole basin of this river having been taken away from
the original Alleghany drainage. But (J. obscuras has not been taken over. Ac-
cording to Davis (1889, p. 248, see also above, p. 430) this stream-piracy fell largely
into Pretertiary times, and although we are to assume that it continued during sub-
sequent times (p. 430), it must have been rather slow, and insignificant, chiefly so in
Glacial and Postglacial times, which alone are to be considered in the case of C. oh-
scurus. Although this species was present in the Alleghany River drainage, it did
not go up into the headwaters, remaining away from the actual divide for a distance
of about ten to twenty miles. Under these circumstances, as stream-piracy was only
going on at the headwaters, no good opportunity was offered foi- this species to cross
the divide.

In Cambria (bounty the continental divide bends to the east, and is transferred
to the main chain of the Alleghanies (Alleghany Front) ; but the eastern boundary
of (J. ohscvA-'US does not follow it. Here it is the (^'hestnut Ridge which constitutes
the boundary, beginning in southern Indiana County, and continuing through
Westmoreland and Fayette ( 'ounties to the southern state-line. Generally C.
obacurus does not pass beyond this ridge into the higher parts of the Alleghany
Plateau, Ijut theie are two exceptions. It is found in the Loyalhanna River in the
Ligonier valley, and in Indian Creek, and in this region it is not the Chestnut
Ridge, but the Laurel Hill Ridge which forms the eastern boundary. In the Cone-
maugh River and the Youghiogheny, this species has not been able to pass up-
stream beyond the (Jhestnut Ridge, since both rivers become very rough above this
point, and this roughness apparently existed also at the end of the Tertiary Period,
when the rivers descended, through the Chestnut Ridge, from the elevated Old Ter-
tiary peneplain to the late Tertiary base-level, at which they were then flowing.'"

*' Acoordinu; to Campbell (1903, p. 292) the peneplain of southwestern Pennsylvania, elevation 1200 to 1300 feet,
is identical with the Old Tertiary Harrisburg peneplain ; and according to White (1896, p. 377), the Old Monongahela
( with the Youghiogheny) of Late Tertiary age was about at base-level. Stevenson ( 1878, p. 259) has called attention
to an old terrace of the Youghiogheny at Connellsville, which apparently corresponds to the late Tertiary base-level,
200 feet above the present level (894 feet) at about 1100 feet above the sea. At Confluence it is 1820 feet high, thus
giving to the river betweeu Confluence and Connellsville a fall of about 700 feet at the end of the Tertiary At present
the fall of the river is only 432 feet between the points named. Although the identity of the old terraces is not demon-
strated, the difference of elevation is so great that a considerable fall of the Tertiary river is beyoud doubt, and thus at
that time a barrier to the upstream dispersal of C. obscuras must have existed here.

ORTMANN: THE CKAWFISHES OF THE STATE OF PENNSYLVANIA 445

As lias been repeatedly mentione<l, C. obscunis has been discovered in Wills
Creek, a stream which belongs to the Potomac drainage, at Hyndman, Bedford
County, Pennsylvania, and EUerslie, Maryland. I "his localit}' is entirely isolated
iiiid about 40 to 50 miles distant from the nearest parts of the main range in West-
moreland and Fayette Counties, separated from the latter by that part of the Alle-
ghany Plateau which is included between Chestnut Ridge, Laurel Hill Ridge, and
the Alleghan}' Front. In this region, chiefly in the drainage of the upper Youghi-
ogheny and Castleman Rivers, C. obscurus is missing, of which fact I am quite posi-
tive, having searched for it in vain at the following localities : the Youghiogheny
River at Ohiopyle, Fayette County, same river and Laurel Hill Run, Confluence,
Somerset County; Youghiogheny River, Selbysport, (iarrett County, ^Maryland ;
Castleman River, Rockwood, Somerset County ; Flaugherty Creek, between Meyers-
dale and Keystone, Somerset County.

Under such conditions stream-piracy is out of the question. For some time I
suspected that C. obscurus might be present in other parts of the upper Potomac
drainage, but this is not the case. I have investigated the Potomac River at Cum-
berland, Maryland, and above Cumberland (Rawlings, Alleghany County, Mary-
land), and further up, where it forms the boundary between Garrett County, Mary-
land, and Mineral and Grant Counties, West Virginia ; but I have not seen a trace
of this or any other river-species. Below Cumberland G. limosns turns up. Thus
the presence of C. obscurus in Wills ('reek is very local, and restricted to only a
small part of the creek. I found it at Ellerslie, Maryland, but not below this point,
although I investigated the whole creek from Mt. Savage Junction to the Pennsyl-
vania state-line. At Hyndman it is (juite abundant, but only below a point about
half-a-mile south of the railroad station, thus occupying only aliout eight or nine
miles of the creek.

These facts are rather strange, and, I believe, can only be explained by the
assumption of artificial introduction by human agency. 1 do not think that it was
necessarily intentional, but it may be due to accidental stocking of the creek with
this species, which is not altogether improbable, if we consider that in this region a
good deal of fishing is done, and that fishermen from places between Pittsburgh and
Connellsville go over this whole region, and frequently use crawfishes as bait, cap-
turing them in one part of the country, and carrying them for their purpo.^^cs to
other parts. If ('. obscurus has not been tran.sported in thi.s way to Wills ( 'reek,
intentionally or accidentally, 1 have no other explanation to ofler.

The above theory as to the origin of the distribution of the group of C jtroiiin-
quus explains the facts, as far as I can see. Our knowledge of the ilistribution of

446 MEMOIRS OF THE CARNEGIE MUSEUM

C. propinquus and of C. j^rojyinq^ms scmborni is rather unsatisfactory, but none of
the known facts is opposed to our theory. With refei-ence to C. ohscurKs in Penn-
sylvania, I think our assumptions are well supported. Cumbanis obscurus is a Pre-
glacial form, helonging to the Old Mononguhela {or Spencer) River, which survived dur-
ing Glacial times in the Jiradiraters of this river {Lake Monongahela), and spread ant,
in Pustglaciid tinas, orer the irlmle of the Upper Ohio dreihuige {in ad<liti<in to the
Ohio a)id Monongalnla, orcr tite drainages of the Beaver and thr Alleghang Ilivers), (tnd
iras onlji checked in its disjx rsal in the direction, toirard tin: riionnfains hg the roughness
(f tlie streams. Tlie Ohio River of Postglacial times opened a way down stream,
but C obscuriis was unable to spread in this direction, since these parts were occu-
pied by another closely allied species, C. propmieptus sanborni. It has slightly
entered upon the territoiy of the latter (Fishing Creek), hut has not been able to
ci'owd it out or to coiKjuer it. Similar conditions prevail in tlie Lake Erie drainage,
which has been reached in consequence of stream-piracy, or else, by the help of
nrodern canals. Here it came into contact with C propinquus. In both cases (in
West Virginia and Erie County, Pennsylvania) we see that the (jtlier species show
indications of an inclination toward C. obscurus. I believe we have to deal here with
]ii/J)ridization, but tliis will be discu.ssed later. Finally the species has crossed over
into the Lake Ontario di-ainage in the region of the headwaters of Genessee River,
presumably in consequence of stream-piracy. In the upper part of this system, in
Pennsylvania, it did not find any competition, and is alone represented there, while
in the lower part, at Rochester, N. Y., it is again fountl associated with C. propin-
quns. Further details with respect to these parts are not at hand.

Comparing the distrilmtion of tlie //rr*j>/»7/n/.x-group with Adams' scheme of
Postglacial dispersal of the biota of North Ameri-ca, we see at a glance that the whole
group belongs to his northea-^tcrnbiata of the second irare (Adams, 1905, p. 5S). The
biotic preserve of this element, during glacial times, was not far from the southern
edge of the ice, in what is now the ( )hio drainage, but it was re.stricted to this
western part, and was not extended east of the x\lleghany Mountains. In Post-
glacial times this grou[) advanced northwai'd, firming part of the second wave,
which is most clearly seen in the ])resent distribution of (J. propinqmi^i, which largely
entered the coniferous forest-lielt in JMichigan, New York, and < 'anada. 'I'lie other
two forms (C propin(ptns .^oidxjmi and ('. olm-nrn.^) did not take nuicb jiart in the
migration of this wave, since they found a harrier to the noi-tli in tiie shape of the
continental divide, and then, after they had crossed this divide at certain points,
they found competition in C. [jropinquus, which had populated the whole St.
Lawrence drainage at an earlier date ("biocenotic barrier"). In New Y^ork state.

ORTMANN: THE CRAWFISHES OF THE STATE OF PENNSYLVANIA 447

liowover, C. ohscurus has advanced north in the (Jenessee basin to a considerable
distance.

3. ('ambarus hartoni.

a. Sammar;/ of Fads. (See pp. 381-38G.)

Cmahanis hartoni is very uniformly distributed all over the state, being, how-
ever, rather scarce in the extreme northwest in Erie ( 'ounty, where it is replaced
by the form C. bartani rohishis. 'We shall discuss this later.

The species extends considerably beyond the limits of this state, chiefly toward
the southwest and northeast. In these directions it ranges from Tennessee and
North Carolina to New Brunswick and Quel)ec. Westward it reaches central Ken-
tucky and southern Indiana. The Atlantic Coastal Plain is apparently not invaded
by it to any considerable degree.

We clearly see that its range follows the main strike of the Appalachian system,
and knowing that ecologically this species is a form of the rapid and cool waters
of the uplands and mountains, living preferably in small streams and even springs,
we understand that the distribution must be entirely different from what we have
learned with reference to the river-species already discussed.

In Pennsylvania conditions seem to be favorable for this species everywhere,
possibly with the exception of a very narrow strip on the eastern border, along the
Delaware River (coastal plain); but even here it approaches the lowlands very
closely, the Piedmont Plateau reaching the river at many places.

In the mountains elevation is no barrier for it, I found it mv-self at 2.G00 feet on
Laurel Hill Ridge, west of Jennerstown, and at 2,300 feet near Sandpatch, Somerset
County, and at other places at elevations not much less (Chestnut Ridge in West-
moreland County ; near Cresson. ( 'anibria ( ounty ; Keating Summit, Potter ( 'ounty).
At Davis, Tucker (bounty, WestMrginia, I collected it in Ijlackwater River at 3.050
feet, and Faxon, ISOS, p. (MD. records it from Roan Mountain, North Carolina,

6,000 feet.

b. Origin of the dintribiition of C. hartoni.

The first point is to ascertain the center of radiation of this species. As I have
pointed out in a previous paper (1905, p. 121). we must regard the southern section
of the Appalachian system as the original home of the subgenus liartitniu.f. to which
this species belongs, and (/. c, p. 122) the advance and dispei-sal of the subgeiuis
took place over the eastern mountains of the T'nited States, the axis of the dispei^sal
being directed from southwest to northeast.

We have reason to believe that the origin of this species falls into Preglacial
times, it being rather primitive within the subgenus (at least in comparison with the

448 MEMOIRS OF THE CARNEGIE MUSEUM

fJiogcvcs-gro\i\}). Jf this is tlie case it very likely extended in the Tevtiiiry at least
as far north as at present, but the advancing ice of tlie (llacial Period must have
driven it south again, and it nnist have survived in the mountains of Virginia,
West Virginia, and states further south. Possibly southern Pennsylvania formed
part of its preserve in Glacial times, for th.e peculiar preference of this species for
cold water admits this assumption. Be this as it mav. it is certain that after the
retreat of the ice this species advanced, occupying or reoccnpying the whole state
of Pennsylvania, and keeping on in its northwai-d migration, until finally reaching
its present range.

This advance in a northeastern direction clearly agrees with Adams' tliird h.ujli-
ivai/ uf dlsj)ersal {1902, p. 123) along the Appalachian chain, and V. Intiioni also
belongs to the northeastern biota of the second Postglacial wave (1905, p. 58). What
is interesting in this case is that an a(|uatic creature follows here the main strike of
the mountains, independent of the drainage systems. I have })reviously called
attention to this fact (l'.)05/', p. 129), and have pointed out that this is rather the
rule with the subgenus Bartoirias (this has been oKserved already 1)V Faxon, 1885*7,
p. 179). There is not the slightest doubt that this peculiarity is connected with the
ecological laws governing this species. It lives generally in the region of the head-
waters of the streams, where the dendritic conformation of the drainage sj'stems and
their mutual interlocking favors frequent shiftirjg of the divides in consequence of
stream-piracy.

Moreover, '''. hartoni is a form which habituall}' leaves the water. It is found
not oidy in small streams, but also in springs, often at places where there is a very
scanty suppl}^ of water, and this has fcM'ced it to often assume burrowing habits.
Like ('. ohsciirvs it is al)le to survive exposure to the open air for a consideral)le time,
provided the temperature is not too high, and thus it is easy to imagine that it may
cross over divides during rainy oi' cloudy weather, wandering from spring to S[)ring
in the mountains. ( )n the other hand, we see that C imrtoni is not entirely absent
from larger streams, and if once established in a small part of the drainage of a cer-
tain I'iver it may easily be distributed over the rest of it l)y simply following the
course of the stream. Thus it is not strange that this species has occupied the whole
of the state, and this uniformity of distribution is chieily i\\w to the fact that the
whole of I'ennsylvnnia is hilly or mountainous, oHering everywhciv favorable condi-
tions for this species. The genei'al dispersal is due to two cau.ses : first the ability of
this species to cross watersheds b}' active migration ; and second to stream-piracy,
which has apparently plaj'ed a considerable pait in its dispersal.

it should be noted, as we have seen above, that the size of this species decreases

ORTMAXN' : THE CRAWFISHES OF THE STATE OF PENNSYLVANIA 449

markedly in the eastern section of the state. This fact is significant, in so fai- as it
points out that the center of radiation for the state of Pennsylvania is rather on the
western side of the mountains than on tlie eastern (see Adams, 19M2, p. 122. "fnitrth
criterion for the detenu inat ion of centers of dispersaV).

4. Canibarus hartoui robustus.
a. Siuiiiiiarij of Facts. (See pp. 390-391.)

This form is found in Pennsylvania in a rather continuous area in the extreme
northwest, in McKean, Warren, Erie, and Crawford Counties, hoth in the Alleghany
River and the Lake l^rie drainages. It is often associated with the typical C. hartoui,
but has been found at different localities in Erie County without the latter. In
addition it is not rare in the northeastern part of Allegheny County in the Alle-
ghany River, and its tributaries, and has also been found in Chartiei-s Creek, in
southwestern Allegheny County. Here it is always associated with the typical form.

In no other part of the state has this variety been discovered, and it is very im-
portant to note that no trace of it has been found in southwestern, central, southern,
and eastern Pennsylvania. Although C. hartoui is abundant in these parts, and
particular attention has been jjaid to the possible presence of C. hartoui rohnstus,
all attempts to find it have failed, and I feel justified in asserting that it is ab.sent here.

I am not so sure of this with reference to the region lietween Crawford and ^^'arren
Counties on the one side, and Allegheny County on the other. 1 have searched in
this section for C. hartoni rohustiis, for instance near Tionesta, Forest County, at Oil
City, Venango County, in Mercer and northern and central Butler Counties, and near
Kittanning and Mosgrove, Armstrong County, l)Ut did not discover it. However, it
is possible that it is present along the course of the Alleghany River, in the river itself,
and some of its tributaries, in Forest, \'enango, and Armstrong Counties. In .some of
the places mentioned 1 did not strike streams which looked very favoralde, Ijcing gen-
erally not large enough. Yet in Erie and Crawford Counties I sometimes found this
species in rather small streams. Conditions in Otter Creek, Mercer County, Slip-
pery Rock (Jreek ami Tiioni (icek, Butler County, were apparently identical with
those under which it is generally found in Ij-ie County, but this form was not found.

h. Origin of the distrihutioti <f C. hartoni robustus.

Considering that the true C. barlotii roliu.'<tiis is a iiorthern form, being found

outside of Pennsylvania in northern Ohio, western New York, and Canada (St.

Lawrence Basin), its center of distril>ution .seems to be at tlie nortliwestern edge of

the range of C hartoui, in the St. Lawreiuv drainage. In Peim.sylvania, however.

450 MEMOIRS OF THE CARNEGIE MUSEUM

it has crossed the continental divide, and has invaded the Allegiiany River drainage
in McKean, Warren, and Crawford Counties, and possibly has come down the
Alleghany River as far as Allegheny Count3% spreading into some of its smaller
tributaries."" This assumption seems plausiV)le if we take into consideration only the
Pennsylvanian material and that tVom the St. Lawrence Basin. Wo would have
here a case of distril)Ution which is entirely unique. C. Jxirtorii rohiistus should
then be regarded as a Postglacial form, which originated in the St. Lawrence
drainage, and in Pennsylvania spread southward, coming fi'om the north.

But there are objections to this view. C. hartoni rohushts has been reported also
from Virginia, Maryland, and Kentucky, and this, of course, would not be in favor
of this theory. However, as has been said above (p. 392), I am inclined to believe
that this southern form is not the same as the northern. If this view should be
correct, I should regard C. robasfns as a good species, and then the above opinion
would hold good.

But further, the morphological characters of C. hdiinni roJxiMux, as compared
with those of the typical hartoiii, are distinctly more primitive. The shape of the
rostrum is decidedly more archaic, the original form of the rostrum in the subgenus
Barformis being rather elongate, and not short and broad as in ('. Ixirioni. The
frequent presence of distinct lateral spines on tlie carapace is undoulitedly a primi-
tive character; and the ecological peculiarity of prefei-ring larger streams than are
haunted by the typical fjrm might also be I'egarded as a remnant of more piimitive
conditions. This, of course, would be strange in a Postglacial form, originating within
the glaciated area, and we rather ought to expect a higher differentiation than the
original, typical form.

Until the question of the identity of our northern C Innioni mJiuMuf! with the
southern form, which bears the same name, is settled, we cannot form a tiiial opinion.
If both forms should be actually identical, we might have to deal with two races of
(J. hartoni, an older one (C. bartuni rohvdus), Avhich possibly constituted a first wave
of migration from southwest to northeast, which was overrun and crowded out by
a later wave, consisting of C. Ixuioiti fijpicus. Remnants of the older stock have
been alile to survive only at a few, scattered localities in the south, while in the

'"The Alleghany Kiver, between Sandy Creek and Verona, lias been investigated repeatedly. It is a curious fact
that Dr. D. A. AtkiDson collected here a large number of C nl>«ciiriis on September 17, 1900, but not a siugle rubnstns.
I was at the same place on June 1, 1004, together with Dr. Atkinson and Dr. O. T. Cruikshauk, but we did not collect
this form (conditions were unfavorable) ; on November 19, 1904, I spent a whole day there, collecting numerous C. nb-
scurus, and a few C. hartoin (typical ), but not a single ro6Hs(»swas seen. When I visited thisplace again, on September
7, 1905, I secured within a short time six specimens of C. hartoni robustus, and on September 30, 190.5, I found three fine
specimens a little further up the river, at Hulton, although I did not hunt very diligently. Is it possible that the
migration of this form down the river is going on ? Does it gradually become more abundant ?

ORTMANN : THE CRAWFISHES OF THE' STATE OF PENNSYLVANIA 451

northwest a more continuous and solid colony lias remnined. The scarcity or even
absence of the typical harloni in Erie County, Pa., which in our state is the chief
domain of C. bartoni rohuslus, would support this view. C. harttmi has not yet in-
vaded this region to such a degree as to crowd out the other form. Though I must
confess that it does not strike me as very likely that the smaller form should be able
to conquer the larger one.

Further investigations on this question should be made outside of this state.

5. Camhanis carolinus.
a. Sumniari/ of Facts. (See pp. 396-397.)

This species (see PL XLIII) is found in Pennsylvania in the southern part of
the Alleghany Plateau, between the Chestnut Ridge in the we.st, and the Alleghany
Front in the east, preferring the high valleys in this region. l)Ut not going up to the
highest elevations of the mountains. Thus, although abundant near Meyersdale in
Somerset County, it does not go up the valley of Flaugherty Creek toward Sand-
patch. I have searched for it in vain between Meyei-sdale and Keystone, and at
Sandpatch. In a northern direction this species ranges in the valley between the
Chestnut Ridge and the Laurel Hill Ridge as far as southern Westmoreland County.
Here the northern boundary is formed by the cross-divide in this valley separating
the headwaters of Indian ( "reek from the Ligonier \'alley. I am quite positive of
this boundary, since I have .searched in vain for chimney-builders all over Ligonier
Valley from Idlepark (below Ligonier) to the sources of the Loyalhanna River.
Coming across the divide to Jones' Mills, within a short time I discovered this species.
In the longitudinal valley between the Launl Hill Kidge and the Alleghany Front,
this species has advanced further north. It has crossed the divide between the Cas-
tleman River drainage and that of Stony Creek (tributary to the Conemaugh), and
I found it near Listie and Windl)er, in Somerset ( 'ounty. At the latter place it seems
to attain its northern boundary. At all events I failed to find it near Ix)vctt in Cam-
bria County, in the high valley of Laurel Run. which to all appearance allbrds con-
genial conditions for its presence being rather swampy in many places. I have also
searched for it unsuccessfully in the region of ( "resson, Cambria (!'ounty, and at
several places further north.

The rest of the range of this species is entirely to the south of this state, in
Maryland, West Virginia, Virginia, North and South Carolina (disregarding the
isolated report from the Indian Territory, in which 1 do not put much faith). No
particulars are known about its boundaries, but in tliis rcu'lon also it is restricted to
the mountains.

452 MEMOIRS OF THE CARNEGIE MUSEUM

h. Origin of the distribution of C. carol irius.

Generally, conforming to tlie subgenus Bartonius, the center of radiation of this
species is to be sought in the southern part of the Appalacliian system. It has fol-
lowed in its migration the strike of the mountains, keeping to the higher parts of
the latter. Thus it has entered soutliern Pennsylvania, being restricted here to the
highest portions of the Alleghen}^ Plateau.

The lowest elevation at which I found it is at Ohiopyle, Fayette County, 1,250
feet, and at Dunbar, P'ayette ('ounly, 1,260 feet. (At the latter place a few strag-
glers— two specimens — were taken as low as 1,070 feet, associated with (J. diogenes,
but here they had apparently come down from the top of the mountain, where this
species was abundant at 1,260 feet.) All other localities in Pennsylvania were
highei', generally between 1,500 and 2,000 feet.

The northern boundary of this species in our state is formed by two difi'erent,
opposite features in the physical geography. Between Chestnut and I^aurel Hill
Ridges it is a cross divide of the longitudinal valley ; between Laurel Hill and the
Alleghany Front tlie deep erosion of the original longitudinal valley by the head-
waters of the Conemaugh River forms the boundary. We do not know much of the
geological history of this I'egion, but it seems to me that the floors of these high
valleys with their extensive clay deposits form a part of a former base-level, namely,
that of the Old Tertiary peneplain identified with the Harrisburg peneplain by
Campbell (1903, p. 293). In northern Somerset and southern Cambria Counties
this has been eroded by the ( 'onemaugh system, thus removing a good deal of the
clay bottoms, which seem to l)e an essential condition for this species, and conse-
quently the lack of this feature, or its interruption l)y the < 'onemaugh system at the
northern end of Somerset County, has formed here the Ijarrier to the dispersal of C.
carol inus.

To all appearances C. carolinus is a Postglacial immigrant into this state. The
northern boundaries in both of the longitudinal valleys are rather insignificant, and
we should expect that C. carolinus, being a chimney-builder and able to leave the
water for a considerable time, should be able, like'V'. hartoni, to cross boundaries of
this character. We should even expect that it would be better fitted to do so than
C. bartoni. In fact 0. carolinus must have done so repeatedly on its way from the
South, being found in the upper drainages of rivers running in difierent directions,
for instance, the upper Youghiogheny in Maiwland, the u])per Potomac in ^laiy-
land and West V^irginia, upper Decker's Creek (tributary of the Monongahela), and
upper Cheat River in West Virginia.'' That it has been checked in I'ennsylvania

^' As to stream adjustments and migration of divides in Garrett County, Maryland, See Abbe, 1002, p. 47, .53.

OKTMANN : THE CRAWFISHES OF THE STATE OF PENNSYLVANIA 453

by sucli minor barriei"s as an insignificant divide and a deepl}' eroded system of
valleys, renders it very probable tliat these obstructions are only temporary, and
may be overcome in time, and, on the other hand, that tlic immigration of tills
species is rather recent, its northward migration being not yet finished, but only
temporarily stopped.

The fact that this species is restricted to a narrow strip within the mountains
is clearly due to its ecological habits. It prefers a certain altitude and clay bottoms.
'riic lattur are found in Pennsylvania chiefly on the Old Tertiary base-level, and this
is represented to a large degree only within the mountains. East of the Alleghany
Front and west of the Chestnut Ridge only insignificant renuiants of this base-level
are found, and thus this species is missing.

AVe do not know anything about the Preglacial history of this species, and the
facts at hand furnish no evidence with regard to this question. According to the
mor{)hological characters, and compared with C. diogcncs and C. monoiKjahusis, we
must assume Preglacial age for it. Its immigration into Pennsylvania probably is
Postglacial, and thus it po.ssibly belongs to Adams' third wave of migration, starting
from the southeastern center (Adams, 1905, p. 62). However, in analogy to C.
monongalensis it may belong to the second wave, and the northeastern biota (see below
under C. monongalensis).

6. Camhanis monongalensis.
a. Summari/ of FactJi. (See pp. 400-401.)

Cambarrcs monongalcnisis occupies in Pennsylvania (.see PI. XLllI) a continuous
area in the southwestern part of the state. Toward the east, beginning at the south-
ern state-line, the limit of the distribution is formed by the Chestnut Ridge as far as
the point where the Loyalhanna River cuts through this ridge in Westmoreland
County. From this point the lioundary follows the Foyalhanna to the north, and
continues northwestward along the Kiskiminetas River. From the point where the
Kiskiminetas empties into the Alleghany, the latter river, ami further down the
r»hio, form the northern boundary of this species, until the Ohio leaves the state in
Reaver ( 'ount}'.

Within this area this species has been found wherever it has been .searched for,
namely: ni (ireene, Washington, and southern Heaver Counties ; in the northwest-
ern section of P^'ayette County ; in the larger part of Westmoreland < "ounty. and in
southern .Mlegheny County. It has also been traced beyond the boundaries of the
state in a western and southern direction : it is found all over the Panhandle of
West Virginia (Hancock, I'rooke, Ohio, and Marshall ( 'ountii'sK and has also been

454 MEMOIRS OF THE CARNEGIE MUSEUM

found at Morgaiitown, Monongalia County. It undoubteilly goes; further south in
West Virginia, hut no records are at hand from these parts.

The writer was unable to discover this species in the state of ( )hio (Harrison,
Carroll, and Stark Counties), and its absence north of the Oliio-Alleghany Kiver is
well established (with one exception to be presently mentioned). Particular jtains
have been taken to ascertain the latter fact. While it is very abundant in Alle-
gheny County, south of the Alleghany and Ohio Rivers, the writer has not in a
single instance found it north of them. He has searched in vain at many localities
in northern Beaver, northern Allegheny, in Ai-mstrong, and Butler Counties, and
further north. At one single locality, however, on the northern side of the Alle-
ghany River it is present. It was found l)y I>r. U. A. Atkinson near Squaw Run,
at Aspinwall, Allegheny County (more correctly near Claremont). This seems
to l)e a very re.stricted locality. The writer did not visit it himself l>ut he hunted
all over the region aromid it from Aspinwall to Squaw Run, and beyond to Mon-
trose, Powers Run, and Harmarville, without discovering additional localities for
the species. Thus it seems that this locality is the only one on the northern side of
the river, and we are able, as we shall see below, to explain its presence there.

This species is generally found at elevations from 900 to 1,200 feet; and it rarely
descends to <S00 feet or less. The lowest altitude at which it was found is 790 to 800
feet at Colliers, Brooke County, West Virginia, and at about the same (estimated)
elevation it occurs in Fern-Hollow and Nine-Mile Run, Pittsburgh.

h. Origin of ihe (Jisfrihiitii))/ of C. moi/onijalcims.
The distribution of this species outside of the state is very incompletely known,
and consequently we cannot form any opinion as to its center of dispersal. ( 'on-
sidering, however, that it is clearly a form cognate to (J. carol iniis, we may safely
assume that it also came from the south, from West Virginia. C. carol iiii(>^ and ('.
moiionyaJcnsis .seem to be two parallel species, closely connected genetically, the
one belonging to the Old Tertiary base-level within the mountains, (elevation 1,200
to 2,000 feet), the other to the hills west of Chestnut Ridge (elevation 900 to 1,200
feet), formed l)y the Tertiary erosion of this base-level. The areas of both are sepa-
rated by the escarpment of the Chestnut Ridge, and l)oth have probably migrated
on parallel lines.

C. mononijalcniii-'t must have invaded Pennsylvania and the Panhandle of West
Virginia from the south, being confined to the region between the Chestnut Ridge
and the Ohio River. That in this case a large river forms a barrier to an aquatic
creature is highly interesting, but is easily explained by the ecological habits of the

OHTMANN : THE CRAWFISHES OF THE STATE OF PENNSYLVANIA 455

species. Living underground near springs, and positively avoiding even the smaller
streams, it is clear that a large river does not offer congenial conditions, and that it
even may become dangerous to single individuals when they are accidentally swept
into such a stream, they then being unable to get out and reach more favorable
locations.

The restriction of this species to a comparatively small area in southwestern
I'ennsylvania is thus easily explained. The northward expansion was stopped by
the first large river flowing from east to west in this region.

A few additional points need discussion. Coming from tiie south, this species
migrated largely in the direction of the great tributary of the Ohio, the Mononga-
hela, and this river did not offer a barrier. It is different with the Youghiogheny.
The latter comes through the Chestnut Kidge, and should form a barrier to the east,
preventing it from entering Westmoreland County and eastern Allegheny County,
On the other hand we see that this species has in one instance crossed the Alleghany
River, i do not think tliat this is due to direct and actual crossing of the rival's,
but to a shifting of their courses, of which we have many evidences. The geological
history of the rivers of this region is as follows. The highest elevations of the
country between Chestnut Ridge and the Ohio River are ver}' uniform, rarely going
beyond 1,200 or 1,300 feet. This seems to represent an old base-level, belonging to
Old Tertiary times, according to Campbell (1903, p. 292 ff.). Tliis was again cut into
by a drainage system belonging to the Old Monongahela or Spencer River, which,
at the end of the Tertiary, was running again at base-level (White, 1<S96, p. 377), at
an L'k'vation of about 900 feet (in the region of Pittsburgh), having eroded its valley
about 300 feet below the Old Tertiary base-level. This river was rather sluggish
and frequently formed ox-bows. The most important old channels, having regard
to the matters in hand, are in the first plaee those which are marked by a terrace
about 225 feet above the present river (at Pittsburgh), both along the Youghiogheny
and Monongahela, at Mcdveesport, Allegheny County, to the east of the present
rivers, which, consequently, have been shifted to the west (Jillson. I<sy3. p. 12, pi. 1).
East of Pittsburgh we have an old ox-li«)w of the Monongahela in the '' Wilkinsburg
Valley " at about the same level (Jillson, ibid., p. 8 IT.). Here also tiie river has been
shifted to the west. These instances are sufficient to show tiiat repeatedly and at
various places opportunities were offered to ('. nionongaloi.ii.'^ to passively cross the
Youghiogheny and the Monongahela Rivers on aceount t>f the shifting of the latter,
and the same .seems to be the case with reference to the Allegheny River in the
region of Squaw Run. According to Jillson (1. c, p. 10), there is a terrace 25<> feet
high belonging to the same general level as those mentioned above, one to two miles

456 MEMOIRS OF THE CARNEGIE MUSEUM

north of the Allegheny in the region of Claremont. At the same place thei'e is
another terrace north of the river, only 150 feet high, and consequently belonging
to a later period, so that here the final shifting of the river to the south took place
later than in the other cases.

These facts, if they at all influenced the distrihutiim of ('. oiiondui/alciiKis, and I
believe they did, give us a hint as to the time of the immigration of this species.
The shifting of the rivers must liave taken place sometime dining the < dacial
Period, for we know that during this time a considerable amount of erosion was
accomplished, the 900 feet level belonging to the beginning (jf the Glacial time
(Lake Monongahela stage). ''-

This leads us to the conclusion that C. nioibongaiensis must have l)een present in
this region during the Glacial Period, at least during a part of it, and shortly before
these channels were changed."^ It is quite possible that this species had its preserve
in Glacial time not far from the edge of the ice in southern Pennsylvania and
northern West Virginia, and that it began to advance as soon as the ice of the \A'is-
consin stage began to recede. This would fully explain the fact that this species
was able to cross first the Youghiogheny and Monongahela by the help of the west-
ward shifting of these rivers, thus opening a way into eastern Allegheny and M^est-
moreland Counties, and that it later crossed the Alleghany River at Claremont,
when its channel was changed to the present more southern position.

The question remains, why C. mononyalemis, having crossed the Allegliany,
did not advance further north. It is found at Claremont (near Squaw Run), in
a comparatively restricted locality, which is not altogether favorable, being at a
rather low elevation. It has not l)oen able to I'each more favoi-al)le locations at
higher levels, the ascent being more or less difficult on account of the very precipi-
tous hillsides, and moreover it may not prosper here because of the presence of the
competing species, C. dUxjenrs, which is quite al)undant in this region. C. monon-
galevsis is here, so to speak, cornered, and surroimded by unfavorable physical,
ecological, and biocenotic conditions.

If this species existed in this region during Glacial times its Preglacial origin

*'The rivers were cut down even deeper tban they are at present, but the valleys were tilled up again, 100 feet or
more (see Jillsou, 1. c. ). According to Foshay ( 1890, p. 402), the chief erosion falls into the end of the Tertiary ; but
the presence of glacial material in the old river channels, 900 feet high ( East Liberty. Pittsburgh), places the deepen-
ing of the valleys at a later period. Possibly it was connected with and subsequent to the draining oft of Lake Monon-
gahela (Wnite, 1896, p. 3751. which happened sometime during the Glacial Period. Hice (1903, p. •-29) places this
cutting down below the present channels between the Kansan and the Wisconsin stages.

'^The same conclusion is reached when we consider that this species cannot have immigrated before the present
Ohio was formed, that is to say, shortly before the Wisconsin stage (see last footnote). Otherwise the Ohio would not
form its western boundary.

ORTMANN : THE CRAWFISHES OF THE STATE OF PENNSYLVANIA 457

becomes rather probable. This is in keeping with tlie morphological cliaraeters, as
compared with C. cUogenes, for the latter, as we shall see below, is very likely also
preglacial.

We have no evidence as to the Preglacial history of (: mononfjalensis. It may.
howevei-, be said, tliat it must have come from the original home of the subgenus
Badonius in the southern Appalachians. How for north it extended in Preglacial
times we do not know, but the advancing ice cannot have driven it back very far.
This is very probable because it is a form decidedly partial to cold water. With
reference to its Glacial-Postglacial migration it belongs to the northeastern biota and
the second wave of Adams ; but its advance was apparently checked at an early date
by the Ohio-Allegheny River.

It will Ije remembered that with reference to C. carolinus another view has Vjeen
expressed (p. 453). In the case of that species we do not possess any facts which
enable us to fix its time of immigration into Pennsylvania with the same proba-
bility as in the case of C. monongalensis. The present extension of the range of C.
carolinus in the southern mountains classes it rather with the southeaster)! biota. On
the other hand, we know nothing about the southern range of C. rnonongaJensis, and
thus it is at present impossible to properly compare these two species. Their close
affinity, however, and the identity of the ecological conditions under which they
are found (aside from the difference in altitude) render it rather jjrobable that the
parallelism observed between them in some respects may reveal itself also in others.

7. Cambaras diogenes.
a. Summary of facts. (See pp. 405-407.)

Aside from a narrow strip along the Delaware River, in Delaware, Philadelphia,
and Bucks Counties in eastern Pennsylvania, this species covers a large area in
southwestern Peimsylvania, namely all the region occupied by C. mouoiigaleyusis,
ami. ill addition, a belt of a certain width to the north of it (see PI. XLIII). Here
the eastern boundary is formed, as in the case of ('. monoitgaleiusis, by the < "hestnut
Ridge, but it is continued beyond the Loyalhanna River, extending into Indiana
County, and then it follows the divide between the Sus(|uehanna and Allegheny
drainages as far north as the southern extremity of Jellei-son County. From this
region the boundary runs in a westerly direction.

In Jefferson County I found this species at Punxsutawney, ami I have seen
chimneys rather abundantly to the east of this place, when riding on the P>uHalo,
Rochester, and Pittsburgh Railroad, about as far as IJig Run, Jederson County. But

458 MEMOIRS OF THE CARNEGIE MUSEUM

this species is not present in the neighborhood of Du Bois and Falls Creek in Clear-
field County, although favorable localities are numerous there. In the valley of
Red Bank Creek I have looked for it in vain near Brookville, Jefferson County.
Fm-ther west the boundary becomes obscui'e, and is marked by the following locali-
ties: Kittanning in Armstrong County ; Renfrew and Branchton in Butler County;
and Mercer in Mercer County. At all e\'ents I found this species at the jdaces
named, but not north of them. Since no apparent physical feature marks the
boundary in these parts, it reiuains doul)tful whether this is the actual noi'thern
limit of distribution ; but we can narrow down the zone in which it must l)e situ-
ated by naming a few more northern places where 1 searched for it in vain at
the proper places: Goodville, Indiana County;''"' Templeton, Armstrong County
(swampy places of the Alleghany river-bottoms) ; Oil ( 'ity, Venango County ;
the region of the Pymatuning 8wamp near Linesville antl Summit, Crawford
County. It seems, however, that toward the west the boundary has the
tendency to run in a n<jrthwesterly direction, and in Ohio this species reaches
the Lake Erie drainage in Lorain ( 'ounty (Oberlin).

Within the region above defined this species is generally found at a slightly lower
altitude than (J. 'ntononyalcyisis. It is, however, not preeminently characteristic of
the river-bottoms, as I formerly believed (1905«, p. 400), but is chiefly distributed
at an elevation of about 900 feet (more or less), that is to say, at about the level of
the valley of the Old Monongahela River of Preglacial times. At the foot of the
Chestnut Ridge it goes up to L200 feet and more, the highest point being Donohoe,
Westmoreland (Jounty, 1,260 feet, but on the other hand it descends to the river-
bottoms, between 600 and 700 feet, the lowest elevation observed being ou the Ohio
river-bottoms at New Martinsville, West Virginia, about 600 feet. Thus C. diogcnes
is quite abundant at about 900 feet, where C. monongalensis is decidedly rare ; above
this C. diogencs is rai-e, while C. monongalensis has its chief domain at this level ;
and below 900 feet C. diogcnes is also abundant, while C. monongalensis is found
only in exceptional cases.

While the boundaries of this species in Pennsylvania are tolerably well known,
it is quite different with the rest of the range. It appears that the range is divided
into two unequal, discontinuous parts, an eastern and a western. The eastern com-
prises, aside from the small section of Pennsylvania along the Delaware River, the
whole or poilions of New Jersey, Delaware, Maryland, the District of Columbia,
Virginia, and North Carolina. Here it seems to be found exclusively in the Coastal

"This is in the same valley as at Pnuxsutawney, but C. diogenes is positively not found here, since a splendid
place was found for it where it ought to have been discovered if at all present in the neighborhood.

ORTMANN : THE CRAWFISHES OF THE STATE OF PENNSVLVAXIA 459

Plain, not even entering the Piedmont Plateau. The western range begins in
southwestern Pennsylvania and northern West Mrginia, and we have seen that it
here belongs chiefly to the late Tertiary base-level of the rivers. l>ut in Pennsyl-
vania it has entered the glaciated area (Lawrence and Mercer Counties), and thence
has spread westward over the states of Ohio, southern Michigan, Indiana, Illinois,
Wiscon.sin, southern Minnesota, and Iowa. Its main range is here in tlie glaciated
region. But it also occupies localities south of tiie drift, in Indiana, Kentucky,
Illinois, Missouri. Kansns. Arkansas. Mississippi, and Louisiana, extending westward
to Colorado.

b. Origin of the distribution of C. diogeiies.

The first point to be ascertained is whether there is actual discontinuity between
the eastern and western range of tliis species. In western Penn.sylvania I have
positive!}' located an eastern boundary for this species. It is formed by tiie divide
between the Susquehanna and the Alleghany in the north, further south by the
Chestnut Ridge. In the northern parts of ^^'est \'irginia I am also positive that it
is not found east of the Chestnut Kidge in Preston and Tucker Countie.*. We have
the report of Faxon (1885«, p. 71) that this species is found at Deer Park, in western
Maryland, but, as we have seen, this is erroneous (p. 406, footnote 27), and the species
is absent in tliis whole region. 1 have searched for it in vain in Somei-set and
Fayette Counties (east of the Chestnut Ridge) in Pennsylvania, in Preston, Tucker,
and jMineral Counties, West Virginia, and in Garrett and Alleghany (.'ounties, Mary-
land. East of the Alleghany Front, in the Alleghany Mountain region, in the
Great Alleghany ^'alley, and the Piedmont Plateau it is positively absent. It has
never been recorded from anywhere within these physiograj)hical divisions, and I
myself made special search for it in Bedford, Blair, Fulton, and Franklin Counties,
and in the eastern section of Pennsylvania, and further in the Potomac valley at
Cumberland and Hancock, ■Maryland, and Cherry Run, West Virginia. At many
of these places highly favoiablo localities were discovered, but no chimney-buildere
were found. This is the more convincing since 1 succeeded with ease in demon-
strating the presence of this species on the alhivial flats of the Delaware River in
Pennsylvania.

Although our knowledge of the distribution of ' '. '//(»/*/«>• in \'irginia and North
Carolina is far from being complete, all known localities are on the Coastal Plain,
and thus it appears that there is actually a gap in the distribution formed pliysio-
graphically by the Appalachian system and the Piedmont Plateau.

Our knowledge of the distribution in tlie west is also very defective, and more
particularly we do not know anytliing about its southern boundary in West \'irginia

460 MEMOIRS OF THE CARNEGIE MUSEUM

and Kentucky. Thus it is diliicult or impossible to arrive at any conclusion as to
its center of dispersal. But at this point certain morphological observations may
possibly afford some help. We have seen (p. 407) that in western Pennsylvania the
areola is often not entirely obliterated, a condition Avhich is certainly more i)rimitive
than the normal one. Such specimens are quite frequent in southwestern Pennsyl-
vania, while in the other parts of the range they are rather rare or entirely absent.
This flict, according to Adams' (1902, p. 122, 125) eighth criterion for the determi-
nation of centers of dispersal, points clearly to southwestern Pennsylvania. Hei'e
the character of the areola is the least progressive, while in either direction from
this center, to the east and to the west, it is more progressive. This conclusion is
further substantiated Ijy Adams' seventh criterion : " location of least dependence
upon a restricted habitat." We do not know much about the " habitat" of ('. dioy-
cHf.v in the west and south, but it is certain that in western Pennsylvania it is less
restricted than in eastern Pennsylvania. Along the Delaware River I found it ex-
clusively in the black muck of the alluvial Hats, while in western Pennsylvania it
has a much wider range ecologically, being found in clay l)ottoms, on hillsides, near
springs, swamps, and even on sandy or gravelly soil.

Judging from these facts, and also from the general rule which holds good for
the subgenus Bartoni'iis, that its center is in the Appalachian region, we may safely
assume that C. diogenes did not have its center on the Atlantic Coastal plain, nor in
the western parts of its range in the Mississippi basin, but that it is somewhere on
the Alleghanian Plateau ; and since southwestern Pennsylvania and northern West
Virginia are the only parts of this plateau occupied l:)y this species, we have to place
its center here.

Here, as we have seen, it dwells chiefly upon the late Tertiary Ijase-level of the
Old Monongahela drainage, and I believe this was its original habitat. We have
no means to decide whether it was alread}' present in this region in late Tertiary
times ; but the simple fact that it does occupy an area, the physiographical features
of which have developed in Tertiary times, is in favor of this assumption. Further
on we shall become acquainted with another reason for this view. In the Ter-
tiary period its range very likely extended further north ; but the (jJIacial Period
must have restricted it, and its preserve was in the region indicated. In Postgla-
cial times it spread northward again, at least in Pennsylvania. Unlike C. monon-
galensis, the rivers did not form a barrier, for this species largely descended into the
valleys, going down to the river-bottoms and the very banks of the river,'"'^ and thus

"It is found frequently on islands in tlie rivers (Neville and Twelve Mile Islands, near Pittsburgh). I have seen
chimneys on the river banks near Verona, and obtained specimens on the banks of the Kiskiminetas at Kiskiminetas
Junction.

OKTMANN: THE CRAWFISHES OF THE STATE OF PENNSYLVANIA 461

it should liave Ijeen able to cross the latter. Consequentl}' its range extends
beyond tliat of C. mononyalensis.

It is doulitful wliat physical feature constitutes the northern boundary of this
species. In Jefferson, Armstrong, and northern Butler Counties, where the boun-
dary is apparently located, the late Tertiary base-level, to which this species
belongs, loses its identity. Possibly it was not developed at all, and tliis region was
not reduced to base level. .So it might be possible that the roughness of the coun-
try constitutes a barriei' here, and this is supported l)y the fact that the boundary is
located further south in the .Mleghany vt-lle}' than to the east and west of it. On
the plateau-like regions in Indiana and Butler Counties, favorable localities are
abundant, while the narrow Alleghany valley, with tlie deeply cut valleys tributary
to it, do not offer congenial conditions.

It is different further west. In Lawrence and Mercer Counties this .species has
invaded the glaciated area, and is found to the north of the terminal moraine
(see Lewis, 1884, p. 183 and 193, PI. 1 1 and 12), and here prefei-s the swampy depres-
sions formed by kettleholes. But a northern barrier at this point is not evident,
altliough a tendency to a northward extension seems to be indicated.

Having thus invaded the area of the drift, it is not astonishing that this species
spread over large tracts of the latter in Ohio, Indiana, and Illinois. Its presence to
the south of the drift in the Mississippi Valley would then be a continuation of tins
westward migration, which finally varied toward the southwest and the south. 1
have represented it as such (Ortmann, 1905/;, p. 1 23, PI. 3) in a previous paper. Nev-
ertheless this question needs further investigation.

There remains the eastern area of this species on the Atlantic Coa.-^tal Plain. In
the paper just referred to 1 have expressed the opinion (/. c, p. 123) that it ••de-
scended from the mountains" toward tbeea.st, but this apparently needs correction.
Of course the direct way from its supposed center to the Atlantic plain is from south-
western Pennsylvania and iioi-tliern Wi-st N'irginia across the .\ppalachian .-system
and the Piedmont Plateau to Maryland and \'irginia. I!ut the total ;d>sence of this
species from this region is against this assumption. Thoa"e is no possibU' reason whv
it should have disappearefl from the Potomac valley, if it had once been present
there, favorable localities being abundant.

Comparing, however, the present eastern range of < '. <li();ifii(s \y\\\\ tiiat of ('.
liraoiius, we are struck at once by the general similarity. Hotli species lielong to
the ('oastal Plain from New Jensey southwanl, C illni/cueK g»)ing a little further
south, and not (juite .so far nortii, wliik- <'. limusit.t ha.s ent<?red the Piedmont
Plateau, and C. diogenci has not. This similarity induces us to assunu' a similar

462 MEMOIRS OF THE CARNEGIE MUSEUM

origin of distribution, and in that case C. diogcncs would also have come from the
north, being driven back by the advancing ice.

This necessitates the further supposition that C. (lUxjenes is a Preglacial species
(another reason for this has been mentioned above), which extended before the be-
ginning of the Glacial Period further north,, prubaldy from western Penns^dvania
into New York or even beyond. This is not improbable, since the Alleghany
Plateau stretched considerably to the north in Preglacial times (see Powell, 1<S!)(), p.
80), and although the Preglacial features are largely obscured in this region, it might
have been possible for this species to cross over into the coastal plain from western
New York to southern New England or northern New Jersey, skirting the m^rthern
extremity of the Appalachian sj^stem. The coming of the ice must then have i-e-
sulted in the obliteration of the northern connection of the range, thus dividing the
originally continuous area into a western and an eastern subdivision.

According to Adams' classification (1905, p. 58), C. diogenes belongs to the iiorfJt-
easfcni biota, but its dispersal in Postglacial times does not entirely agree with that
of the second ivavc. Indeed there is a slight indication of a northward adv^ance in
Pennsylvania, Michigan, AVisconsin, and ^linnesota, l)ut the main direction was
ivestward from the Alleghany Plateau, and even southward. This is undoubtedly
due to the ecological peculiarities of this species (chimney-builder), it having found
no competition in the directions named. In the eastern section of its range a north-
ward advance is hardly noticeable. Here the species is more restricted ecologically
(apparently a higher specialization ), favoring oidy the black mud of alluvial deposits,
and this very likely prevented its northern expansion. However, its exact distri-
bution in New Jersey is unknown.

8. Suvimar;/ of the Stuelics on Geographical Disfrihiition.
We have been able in the preceding studies to advance a theory for the dispersal
of each of the Pennsylvanian species of crawfishes. It cannot be denied that in cer-
tain points our ideas do not seem to be well supported, but this is chiefiy the casein
instances where our knowledge of the extralimital distribution is defective. It is to
be hoped that similar investigations outside of our state may furni.^h additional evi-
dence to substantiate our conclusions, or if neccssar}', to modify them. This much,
however, is evident, that tlie facts of the distribution of our species are due to two
causes : (1 ) partly to the existing physiographical features of the country ; (2) partly
to past conditions, which have now disappeared. (Jn the accompanying map
(PI. XLIII), we notice the following particulars. In the eastern part of Penn.syl-
vania, along the Delaware River from Trenton, N. J., to Marcus Hook, Delaware

OKTMANN : THE CKAWFISHES OF THE STATE OK PENNSYLVANIA 463

County, a small part of the At/antic Coastal Plaiv enters the state. 'J'lie Delaware
River runs along tlie escarpment of the I'iedmont Plateau ("f;\ll line," See McGee,
1888, p. 122), hut at several places a narnnv space is left, chiefly opposite Trenton,
in Bucks County, and helow Philadelphia, where alluvial Hats are found. These
we may include in the coastal plain, and they are characterized h\' the presence of
C. dioyenes (together with C. limos-iis).

The next physiographic-al divisions of Pennsylvania are the Piedmont Plateau
and the Great Alhghainj I'allci/, reaching from the eastern escarpment of the former
to the Blue Mountain. These divisions form a unit in Pennsylvania. The divid-
ing line between them, South jNIountain, being rather insignificant and obliterated,
chiefly toward the northeast."'"' This fact is also expressed to a certain degree in
the distribution of the crawfishes. Aside from the generally distributed C. bartoni,
we have here C. limoaus, which has invaded this region, coming from the lower
Delaware, Susquehanna, and Potomac. It seems to have spread all over the Pied-
mont Plateau, and also into parts of the Great Alleghany Valley, for in.stance, into
the Cumberland Valley (between South Mountain and the Blue Mountain, called
here the North Mountain, in Franklin and Cumberland Counties). It has also
been found in the Schuylkill and its tributaries in Berks County, but not as yet in
the Lebanon and Lehigh Valleys (northeastern continuations of the Great Alleghany
Valley). Whether the conditions presented here are original or not seems doubtful.
On the one hand it may be that the canals have served to distribute this species ;
on the other hand, pollution of streams may have restricted it. IV this as it
may, the fact remains that the physiographical divisions distinguished as the Pied-
mont Plateau and the Great Alleghany Valley possess a species of crawfish which
is not found elsewhere, except in the Coastal Plain and the Susquehanna Valley.

Then follows the Alleghani/ Mountain region, between the Blue Mountain and
the Alleghany Front (see Willis, 1. c). In the southern and central parts of the
state this section is well marked. In the northern part its western boundary is
obliterated, the Alleghany Front losing its identity. But all the areas which
undoubtedly belong to the mountain region are uniformly characterized by the
presence of only the one species, Cambarvs bartoni, with the exception that C.
limosus is found in the middle Susquehanna valley from Harrisburg upward to
Columbia and Center Counties, and in the Juniata valley up to Ik-dford County ;
and further, C. ofc.scun/.s- exists in Wills ("reek, Bedford ('ounty. I'oth these ex-

"See Willis, 1896, p. 172, and map p. 170-171. Soutli Monntnin is the continuation of the Blue Kiilgc of \ ir-
(;inia, while the Blue Mountain of Peiinsylvania is not identical with the Blue Kid(;r, but is to the we»t (northwest)
of it.

464 MEMOIRS OF THE CARNEGIE MUSEUM

ceptional cases, however, do not represent, in my opinion, original conditions. This
is most evident in the case of G. ohscwrusin Wills Creek, where no other explanation
is possible except that of artificial introduction. With reference to the occurrence
of C. liviosus in the middle Susquehanna and the .Juniata, within the Alleghany
Mountains, I think in this case also a recent immigration took place, favored by
artificial means (canals). This is, liowever, somewhat doubtful, since it is impos-
sible at present to ascertain the normal and original conditions prevailing in eastern
Pennsylvania before modern improvements were introduced."''"

The region containing only 6'. hartoni goes beyond the boundary of the physio-
graphical division of the Alleghany Mountains. In the northwest the Susquehanna
has captured a large part of the drainage of the Alleghany Plateau, and the whole
basin of the West Branch of the Susquehanna is included in the section containing
only C. hartoni. But again a physiographic boundary is formed by the divide
between the Susquehanna and Alleghany river-systems.

All the rest of the state belongs to the Allcghaiu/ Plateau. Here much more
varied conditions prevail with i-egard to the distribution of crawfishes, and this is
chiefly due to the fact that this region was open to Preglacial and Postglacial immi-
gration from the south, southwest, west, and northwest. Aside from ('. hartoni,
which is found everywhere, the following five species immigrated into this region :
C. ■propinqims, C. ohscurus, C. carolinus, C. niowmgalcnsis, and C. diogenes. Since
each of these species had a different center of radiation, a different geological history,
different ecological habits, and since, consequentl}', different barriers existed to the
dispersal, no two species possess the same range.

(J. 'prcpinquus came from the west and northwest in Postglacial times. It belongs
to the Erie basin, and is restricted b}' the divides of the latter. Thus it is confined
in Pennsylvania to the Lake Erie drainage in Erie and Crawford Counties.

C. ohscurus belongs to the Preglacial Spencer River or Old Monongahela, and to
Lake Monongahela of early Glacial age. The Postglacial dispersal includes first of
all the Ohio-Monongahela-Alleghany drainage, and thus generally the divides of
this basin constitute its boundaries, with a few exceptions. In the region of the
upper Youghiogheny and the Conemaugh the roughness of the streams has pre-
vented it from reaching the plateau to the east of the Chestnut Ridge. In Crawford
and Erie Counties it has crossed over into the Erie drainage (due to stream-piracy
or to artificial means), and in Potter (bounty it has found a way into the Genessee
system (due to stream-piracy).

(J. carolinus came from the south, along the high level plains of eai-ly Tertiary

''» The green color on the map, PI. XLIII, should be continued up the Juniata to Bedford County.

ORTMANN: THE CRAWFISHES OF THE STATE OF PESNSYLVANMA 465

age, being partial to extensive clay bottoms. Such conditions are found well
developed only between that part of the Alleghany Plateau which is enclosed
between the Alleghany Front and the Chestnut Ridge. Possibly also elevation has
played a part. Thus it is found only in Somei-set and parts of Fayette and West-
moreland counties. The noi-thern boundary is formed In- rather insignificant and
possibly temporary barriers.

C mononyalcusis is a form parallel to C. canilinus. It also came from the south,
and invaded southwestern Pennsylvania, keeping to locations of less altitude than
C caroHnus. Thus its eastern boundary is formed by the Chestnut Ridge. Its
northward advance was checked by the first large river flowing east and west,
namely, the Loyalhanna-Kiskiminetas-Alleghany-Ohio.

C. diogenes seems to be similar, at least in western Pennsylvania, to C. mononga-
lensis, but it w^as able to cross the rivers northward. The northern boundary is ob-
scure, and may be not entirely due to topographical conditions. Attention may be
here called to the fact that the isotherms have a curve somewhat similar to tliat
formed by the northern and eastern boundary of this species.

Thus western Pennsyh^ania is divided into several sections characterized by their
crawfish-fauna, namely :

1. Area of C. carolinus (containing C. bartoni and carolimis) : Somerset and
southeastern Fayette Counties.

2. Area of C. diogenes and C. monongaleiisis (containing C. obscurus, bartoni,
monongalensis, and diogenes) : Greene, Washington, northwestern Fayette, western
Westmoreland, southern Allegheny, and southern Beaver Counties.

3. Area of C. diogenes iritliont monongalmsis (containing C. obsourus, bartoni,
diogene-i) : northern Beaver, northern Allegheny, northeastern Westmoreland, west-
ern Indiana, southern Jefferson, southern Armstrong, southern Butler, Lawrence-
and southern Mercer Counties.

4. Area of C. obscurus (containing C. obscur us and bartoni): northern Jetlerson,
northern Armstrong, northern Butlei", northern fiercer, the largest part of Craw-
ford, Venango. Clarion, :ind Forest, western Klk, northwestern Potter, McKean,
Warren, and southeastern Erie Counties.

5. Area of C. proj)iiiquus (containing C. jirujiliiiiiins. i)bscurn.'<, tnirtoni): northern
and western Erie and a small part of Crawford Counties.

These are the chief divisions, but there are a few minor diflerentiations. The
greatest variety prevails in Westmoreland County. Its west4.Tn part (west of the
Chestnut Ridge) belongs to two of the above areas (2) and (3). divided by the lA)yal-
hanna River. But besides the valley Ijetween the Chestnut and the Laurel Hill
Ridges presents three different conditions, namely :

460 MEMOIRS OF THE CARNEGIE MUSEUM

(«) Conemaugh drainage, with only one species : ('. Ixirtoiti.

{h) Ligonier Valley, with two species: C. bartoui and uhscnrus.

(c) Headwaters of Indian Creek, with three species: C. obscurus, bartoni, and
carolmus. This latter section also comprises the northeastern corner of Fayette
County.

The greatest number of species found in any one county is five, namely, C.
obscurus, bartoni, earolinus, monoiigalensis, and diogenes. This is the case in West-
moreland and Fayette Counties. They may be found in close vicinity oidy along
the escarpment of the Chestnut Ridge. For the rest four is the largest number of
species found closely associated, namely the four belonging to the second area, com-
prising the range of G. rnonongalensis.

In conclusion, attention should be called to the fact that the terminal moraine
in no case constitutes a barrier for any of the Pennsylvanian crawfishes. (Compare
Lewis' map, 1884, with our maps, PI. XLII and XLIII.) (3f course, for the river-
species the moraine would not be of any consequence, and of the burrowing species,
two, C. carolinns and C. monongalensis, do not reach it at all, while C dlogcve.-^ has
crossed it in the west. But instead of being a barrier the glaciated area rather
seems to offer more congenial conditions on account of the frequency of swampy
places (kettleholes).

The question remains, whether our survey of the state is to be regarded as com-
plete and exhaustive, or whether there might be other species within its limits. This
is suggested by Faxon (1885«, p. 165) as to Cambaru>: blandingi (Harlan). This
species is found in New Jersey at Trenton, on the Delawai'e meadows just opposite
the eastern extremity of Bucks County, Pennsylvania, associated with C. Ihaoms
(Faxon, 1. c, p. 22 and 88). I have made a careful search for it in this part of tbe
svate, and visited this corner twice (C^ept. 1.^, li)()4, and at the same date, 1905).
Having collected this species previously in New Jersey. I was acquainted with its
ecological habits and knew where to look for it. I indeed found localities that
appeared favorable, but I failed to see any traces of the species. I think it is quite
safe to assert that this species is not found in this state.

The case of Lake Erie is a little different. We have records showing that in
( )hio the western extremity of the lake is inhabited by ('(ludidru^ nisficus Girard and
C. immunis Hagen. The former has been reported from Kcilcy's Island (Faxon)
and from Sandusky Bay ((Jsburn and Williamson), and from several tributaries of
the lake. The latter is mentioned from Lake Erie, off Lorain ( ounty (Osburn and
Williamson), and from tributaries of the lake as far east as Lorain County. C.
rmticm is not found anywhere further east, and it seems doubtful whether it finds

OUTMANN: THE CRAWFISHES OF THE STATE OF PENNSYf-VANIA 467

I

congenial conditions in the lake. The specimens taken may have been accidentally
swept into the lake. Thus I do not believe that it will be discovered in the part of
the lake bordering upon Pennsylvania.

C. immunis, however, besides being found in northern Ohio, reappears in New
York. Faxon (1898, p. 654) has recorded it from a tributary of Oneida Lake, and
recently 1 have seen specimens, belonging to the New York State Museum, col-
lected by Mr. V. (\ Paulmier in Rens.selaer Lake, Rens.selaer County. Thus its
presence in New York, upon which I cast some doubt ( 1905/>, p. 134), is to be
regarded as firmly established. However, the connection of these eastern localities
with the western range has not been discovered. If a connection is present at all, it
is to be looked for in the Erie-St. Lawrence basin, and thus would possibly include
the lake shores of Pennsylvania. Yet this connection may not exist, and C. immiinh
in New York may be a recent, artificial introduction, which is not altogether impos-
sible, since we know that the crawfishes used for food in the New York market come
in part from the lake regions (Milwaukee, see Ortmann, 1900, p. 1260), and thus
this species may have been introduced. But this question is by no means settled,
and we should try to obtain further facts.

Finally we may observe that the conditions now existing in the case of the
Pennsylvania!! crawfishes may not be original, but may have been altered by human
agency. The possible influence of canals upon the dispersion of two species. C.
limosus in the east, and C. obscuru.s in ( 'rawford and Erie Counties, has been dis-
cussed in the foregoing pages, and the transplantation of C. uhscuru.s into Wills
Creek has been stated to liave apparently occurred, accidently or intentionall}',
tlirough human agen(;y. No other ca.ses of dispersion beyond the natural bountlaries
l)y artificial means are probable. Put on the other hand certain species may have
become extinct, at le;istin parts of their original range, through human agency. Of
this we have man}' instances, but in our state none has gone so far as to entirely
obscure the original conditions. \\'l' have pointed out above that the absence of C.
limosKs in the Delaware and Schuylkill Rivei-s in the region of the (ireat Alleghany
Valley may be due to the pollution of the streams issuing from the anthracite region.
That these rivers, as well as the Susquehanna are considerably polluted partly by
city sewage, partly by mine-water, is sure (see Leighton, 190:3. p. 112, and 1904.
p. 48), but whether the absence of C limmois in this region is due to this fact, or not,
cannot be settled.

It is dilFerent in the western part of the state. Here C. o/wcv/r«.v originally occu-
piril all of the Monongahela and .Mlcghanv drainages west of the Chestnut Kidge,
but tin re are many streams in which it is now lacking, and in which we must assume

468 MEMOIKS OF THE CARNEGIE MUSEUM

its former presence. This is apparently due to the hirge amount of pollution in
these streams, chiefly by water from mines. The pollution of the Alleghany River
near Pittsburgh, although bad enough from a sanitary standpoint, and due in the
first instance to sewage (Leighton, 1903, p. 122) does not affect the crawfishes, for
they are very abundant here, and the Ohio below Pittsburgh is rich in crawfishes.
But there are many smaller streams contaminated by the waste of coal-mines."'
Such streams are recognized at a glance by the precipitate of reddish and yellowish
sulphate of iron upon their bottoms, and are invariably without life. This is most
evident in the Monongahela drainage of southwestern Pennsylvania (Washington,
Fayette, and southern Allegheny Counties), and also in many smaller streams in
Butler, Westmoreland, Indiana, and Jefferson ( 'ounties, where coal-mines are abun-
dant. The worst conditions prevail in certain tributaries of the Monongahela,
in the Monongahela itself in the Lo3'alhaima below Tatrobe and the Kiskimin-
etas, and in Red Bank and Sandy Lick Creeks. The ( 'larion River is also with-
out crawfishes in Jefferson and Elk ( 'ounties, but this is due chiefly to pollution
by sewage from wood-pulp mills and tanneries (see above, p. 44o). In all these
cases it is evident that C. ob>!Curus once existed here, since remnants of it are left at
many places in some of the clearer and not polluted side streams. Since this pol-
lution of the streams by coal-mines is bound to increase, C*. ohscurus certainly will
disappear from other streams. As we have seen above it was on the point of dying
out in Sandy Lick Creek at Du Bois in 1905 (p. 443, footnote 58). Another case has
been observed in Fern-Hollow Run, Pittsburgh. In the fall of 1903 I found a
small number of specimens of this species left over in some pools once connected
with the run ; a sewer had recently been built here, discharging its jaolluted water
into the run. In subsequent years this species was not again seen, and has entirely
disappeared, as also from Nine-Mile Run, which receives sewage from \A'ilkinsburg
and Edgewood.

It should be added that C. bartoni also is frequently influenced by the contamina-
tion of streams, but seems rather more resistant than C obsairus. In two cases this was
evident, namely, in Mahoning Creek at Punxsutawney, and in Slippeiy Rock Creek
at Branchton. In both cases the streams were only slightly polluted l)y mine-water,
and contained a certain number of specimens of C. burtoni, wliile C. obscurus was
absent. The latter existed at Punxsutawney in a pond connected with the stream,
and at Branchton in a smaller clear tributary, and consecjuently must have once
been present in the two creeks.

A stream or river polluted in a certain part becomes relatively clear and pure

" As to the chemical processes going on in the so-called " sulphur water," see Leighton, 1904, p. 24.

ORTMANN: THE CRAWFISHES OF THE STATE OF PENNSYLVANIA 469

again further down. This is generally seen in the Ohio below Pittsburgh. Although
the Ohio collects all the badly polluted streams of western Pennsylvania, it is itself
not unfavorable to crawfish life. The best instance for this is the Cheat River. At
Cheat Haven, Fayette County, this river is rather clear and teems with life, craw-
fishes and Unionidx being abundant. 1 was therefore astonished at the condition
of this river at Parsons, Tucker ( 'ounty, West Virginia. The water there has a foul
smell, and is utterly unfit for life, which is due to a wood-pulp mill just above Par-
sons on Shavers Fork. Between Parsons and Cheat Haven (about fifty miles) the
water has improved so far that life is not only possible, but is abundant, only the
blackish color of the water remaining as the last result of the contamination.

V. LIFE HISTORY.

Only a few scattered notes have been published on the life-history of any of the
American species of Camharus, and some of them are ratliei- doubtful. The most
complete account is that given by Andrews (1904) on the breeding habits of C. limo-
bi.i^, but even this comprises only a small part of the life-history, and moreover, as
may be seen below, is in part rendered unreliable by the fact that the observations
were not made in the field, but in the laboratory.

My own observations have been almost exclusively made in the field, and were
only occasionally supplemented, or rather confirmed, in the laboratory'. Since it
was my object from the beginning to watch the behavior of the crawfishes under
natural conditions, laboratory-work could not be depended upon, unless controlled
by field-work, and thus the former was neglected altogether.

With the exception of January and Februaiy,'^^ ni}' work in Pennsylvania extends
over the whole year, thus including all seasons. The results are rather satisfactory,
and I am able to give a complete account of the seasonal life of no less than four
species, and by comparison with these the life-history of the other species of this state
may be inferred. Of course I have not been able to solve all questions. For
instance the question of the frequenc}' of moulting in one and the same individual
remains open, since it can only be settled by observing the same individual contin-
uously; but this is impossible in the field. Nevertheless I have found means to
elucidate this question in other ways, although not with absolute accurac}'.

The most numerous and most complete records I possess refer to the common
river-species of western Pennsylvania, C. obscurua, and of this I shall first give an
account.

"From New Jersey I possess observations nintle even in January ami February and referring to C. blandingi, ('.
limosus, and C. bartoni.

470 MEMOIRS OF THE CARNEGIE MUSEUM

1 . Camharus obscurus.

Nothing whatever was previously known in regard to tlie Hfe-hist(jry of this
species. I have observed it during the larger part of two seasons, the dates of actual
observation covering the time from March 28 to November 19 (in 1904 and 1905).

Beginning in spring ( Marcli) it is ascertained that the species is at this time quite
active, being found in the usual localities (under stones in rivers and streams), and
the specimens are of various sizes and conditions, !)ut all agree in having a rather
dirty (mud-incrusted) shell, a sure sign that tlie shell is old and that no recent
moulting has taken place. Tliere are occasional specimens with a very clean shell,
in which moulting has occurred quite recently. This teaches us that during the
winter months as a rule moulting does not take place, but that it begins quite early
in spring, although only in the case of a few individuals. Males of the first form
are abundant at this time, while males of the second form are scarce, and it is chiefly
these newlv moulted males which are of the second foi-m. It seems, however, that
in exceptional cases rather young males (30 to 40 \nm. long) may have gone through
the winter in the second form. The size of tlie males of the first form varies greatly;
tlie smallest found by the writer in spring (May 2, 1905) measure 40 mm. in length,
but specimens between 40 and 50 mm. long are very abundant. All the males
between 30 and 40 mm. long are of the second form, but they are not abundant, as
has been stated. The smallest male found in spring was 31 mm. long. The condi-
tion of the females in early spring corresponds to that of the males, and in this sex
the minimum size is 27 mm. in length.

Very soon an impoi'tant event takes place in the life of the females. Eggs are
laid. No signs of this were seen on March 28, 1905, and March 31, 1905, although
a large number of individuals were collected at tliese dates. But on April 6, 1905,
(in Thorn's Ci'eek, Renfrew, Butler ( 'uunty), numerous specimens with eggs were
taken, some in the very act of spawning. I was able to observe in this species the
peculiar attitude assumed by the female, and the "apron," described by Andrews
for C. limosus (1904, p. 180, fig. 5 ; p. 182, fig. 6). The same was seen repeatedly on
subsequent dates in April, so that April is to be considered as the spawning season.
The number of eggs is rather large, one hundred to two hundred and even more,
but young specimens sometimes have considerably less.

From the beginning of April onward females with eggs are found very regularly
until the end of May. My dates are the following : A}>ril 0, 1905 ; April 10, 1905 ;
April 1<), 1905; April 24, 1905 and 1906; May 1, 1905; May 2, 1905; May 3.
1899 (Williamson and Shafer) ; May 4, 1905; May 8, 1905; May 17, 1906; May
22, 1905 ; May 25, 1905. With one exception (April 15, 1905) I found females with

ORTMANN : THE CFJAWFISHES OF THE STATE OF PENNSYLVANIA 471

eggs every time I collected this species during this period. This rather precisely
fixes the time when the females are '"in berry." They carry eggs during the
months of April and May, hut at no other time of the year, and during this season
all females, with few exceptions, no matter whether they are large or small, have
eggs. The smallest observed with eggs was 40 mm. long. Of couree in the begin-
ning of the spawning season larger females may also be without eggs, but later on
females larger than 40 mm. long are only very rareh' found without them. The
latter generally are newly moulted (having soft or clean shells), showing clearly
that at the beginning of the spawning season the}' were very likely below the mini-
mum size for spawning. Of the few females under 40 mm. long none had eggs.

During the spawning season (April and May) a general tendency toward moult-
ing is observed in all specimens which are not females "in berry." Among the
sterile females, as well as among the males, the old, dirty shells disappear; newly
moulted shells become more and more frequent, and soft shells are frequently
observed. This moulting process in most individuals takes place in the first half of
May, but, as we have seen, some individuals begin as early as March, and in others
the process is delayed till the beginning of June. But by this time all specimens
have moulted under normal conditions, witii the exception of the fertile females,
wliicli iiioiilt after the young are hatched in June.

A remarkable fact in the Ciise of the males is that this spring moult invariably
changes them to the second form.'"'' In consequence males of the fii-st form become
scarcer and scarcer, till finally at the beginning of June all have disappeared and
onl}' males of the .second form are left. Another remarkable fact is that after the
end of the moulting season in spring no very large males are found. While large
males of the first form of over 70 and 80 mm. m length are quite abundant in March,
April, and the fn.st half of May, they become very rare after that time, and the
males of the second foru), which arc then abundant, only in rare instances exceed
the size of 70 mm. in Kngtli, (only two cases on record). During the summer tlie
males are generally less than 70 mm. in length. Large males reappt-ar after the
summer and fall moults begin, and then they are again of the fii-st form.

The question arises what becomes of the large males (over 70 mm. in length),
which are rather frequent in spring. Acconling to the records, we cannot a.ssume
that they moult into the second form, for we should then lind large males of the
second form in summer. Thus it is suggested that the.se large males die ami disjip-
pear. Of this I have found positive evidence in two cases. On .hnie H, 1;mI4, I col-
leeted in the Shenango River at Linesville, < 'rawford County, a large male of the first

"This cliange was first observed by Faxon (18Sl<i, p. 12) in CamUirus ruflicun Girard.

472 MEMOIRS OF THE CARNEGIE MUSEUM

form, 81 mm. long, which was lying concealed under a rock in the usual position.
It was absolutely perfect, without Ijlemish, and with an old, very dirty shell, thus
clearly showing that it had gone through the previous winter. This specimen was
barely alive and to all appearances in a dying condition. A similar instance was
noticed on April 24, 1905, in Wheeling Creek, Elm Grove, West Virginia. Here a
large male of the first form (81 mm. long) was found showing no signs of injury, in
fact in very beautiful condition, but barely able to move. It was kept in water,
but was dead the next day, wliile other specimens collected together with it were
none the worse for their journey to Pittsburgh. Thus it seems that the conclusion
is justified that the largest males of the first form, after having in the autumn at-
tained a certain maximum size, which may be different according to conditions, Init
may be said in general to be about 80 mm. in length, go through the winter, but do
not moult again, and die a natural death in spring.'"

The latest dates at which I found males of the first form in spring are as fol-
lows : June G, 1904, Linesville (the case just mentioned), May 30, 1901, at Waynes-
burg, Greene County ; May 25, 1905, Alleghany River, Mosgrove, Armstrong
County. After the beginning of June, all through the month, and through a large
part of July, no males of the first form have been found, and through the remainder
of July they are scarce. (See below.)

The eges carried by the females hatch at the end of May and the beginning of
June. I found young under the abdomen of the mother on May 30, 1904, on June
5, 1906, and on June 6, 1904. The period daring which the young stay with the
mother seems to be sliort. On May 25, 1905, I found eggs, not yet hatched. From
June 15, 1905, onward all through the remainder of the year I never observed a
female with eggs or young. Between these two dates I have only four records, May
30, 1904, June 2, 1905, June 5, 1906 and June 6, 1904, in three of which the pres-
ence of young ones with the mother was shown. Thus the period when j^oung are
found under the abdomen of the mother is very likely the end of May and first half
of June (about three weeks), and the young crawfishes probably do not remain with
the mother much longer than a week.

Throughout June and part of July no niales of the first form are present ; all
males are of the second form, but they are not very large, reaching a maximum size
of only between 60 and TO mm. The females have got rid of their progeny, and
begin to pioult. The old females may die like the old males, but I have no evi-
dence on this point, except as drawn from analogy to the males, and the fact that

'° A great mortality of males in spring (after copulation in captivity) has been observed by Andrews ( 1904, p.
175) in C. limoaus.

ORTMANN : THE CRAWFISHES OF THE STATE OF PENNSYLVANIA 473

very large females are rare in the latter part of June and in July, and do not become
more abundant till the beginning of August. In addition we now have a new genera-
tion of young crawfishes, hatched at the end of May and beginning of June. After
these have left the mother it is difficult to get them. They are too small, and are
often overlooked, and if captured in the net. are able to e.scape through the meshes.
I)Ut I have seen them at this time, although the first recorded captures are as late as
July 10, 1900 (by Dr. D. .\. .\tkinson), size 26 mm., and July 24, 1905 (by myself),
size 21 to 23 mm. This young generation is easily distinguished from the rest by
its size, being considerably less than 30 mm. in length. The minimum length of
crawfishes in spring is 31 mm. in the case of males and 27 mm. in that of females.

In the middle of July further changes occur. A new period of moulting begins
for the medium-sized and older individuals, which is chiefly noticeable among the
males, since they now again as.sume the first form. The earliest date for the new
males of the first fcjrni is .Inly 11, 1905 (Tionesta and Spartansburg). Altogether
four individuals were taken, all of which had soft shells, showing the fact that they
had recently moulted. Further dates are July 24, 1905 (Deer Lick), July
25, 1906 (Russelton), July 26, 1904 (Deny), July 27, 1906 (Shousetown), and
then in August and the following months they regularly occurred. At first
these males of the first form are scarce, but they become gradually more fre-
quent, till finally at the end of September and in October almost all males have
assumed the first form. This also holds good fur the new generation born at the
end of May and tlie beginning of June. These young ones are about 20 to 23 mm.
long in July; in August I have specimens from 24 to 39 mm. in length; in Sep-
tember from 26 to about 50 mm. in length. About this time this generation l)e-
comes obscured ; for it seems that the rate of growth of the young crawfishes is very
different in different individuals, some gaining during June, August, and Septeml»er.
only about 15 mm. in length, others more than twice that length. They are al>out
10 or 11 mm. long when they hatch. The same fact was observed by Andrews
(1904, p. 202) in C. Iimom.% with even greater differences in size (the length of the
young of the same generation in October being between 22 and 60 mm.).

It is ascertained from the above observations that young specimens, born in
early sununer, already at the end of the first summer (Septemlier and October)
reach a size sufficient to prepare them for propagation, and the males of this genera-
tion as a rule show this by changing into the fii^st form. The smallest male of the
first form, collected by my.self in fall (October 6, 1905), is a specimen from Kittjui-
ning, 38 mm. long, but specimens from 40 to 50 mm. long, and undoubtedly belong-
ing to this generation, are quite abundant at this time. Thus we see that by October

474 MEMOIRS OF THE CARNEGIE MUSEUM

the same conditions are established which were found in early spring. Males of the
first form prevail, and those of the second form are scarce, and generally of a small
size, between 30 and 40 mm. long. Specimens of less than 30 mm. in length are
very rare and represented by individuals of the last generation, which have not
been able for some reason to keep pace in growth with their l)rothers and sisters.
The males are sexually mature, and apparently the females likewise, as we shall
presently see.

Copulation actually takes place now. 1 have quite often observed it in the field,
and made record of the following dates: September 5, 1906; September 28, 1905;
October 6, 1904 ; November 19, 1904. In addition couples were found apparently
preparing for copulation, but not in tlie act, on September 7, 1905, and September
30, 1905. Among the material collected by Mr. W. R. McC-onnell was a couple taken
in cojyuki on September 5, 1905. In captivity I observed copulation on SeptemVjer 8,
1905, and November 22 and 23, 1904, and I have found that it is very easy to
induce couples to copulate about this time (September, October, November), pro-
vided that one male and one female are put in the same jar. In no other part of
the year, and, what is more important, not even in spring (March, April, May) does
copulation take place, either in nature, or in the laboratory. All my attempts to
induce specimens to copulate in spring have l)een in vain, and, of course, in June,
July, and part of August, copulation is impossible, the males not being in condition.
Copulation may occur in August, males of the first form being present, but possibly
the females are not in proper condition before September on account of the delay
of the spring moult. The smallest female seen in copulation was 43 mm. long;
and she undoubtedly belonged to the generation born in spring, thus establishing
the fact that the females like the males are generally sexually mature at the end of
the first summer, and that they are able to produce eggs the next spring. {See
above. The smallest female with eggs was 40 mm. long.)

The above observations and conclusions are founded upon the comparison of
large numbers of individuals, but no single specimen has been followed through all
the different stages of , seasonable development. But to a certain extent it is possi-
ble to ascertain the changes through which one and the same individual has to go,
and to lay down its life history.

The young Cambarus obscunis is hatched at the end of May or tlie Iteginning of
June, from eggs laid in April. The young stay with the mother under the abdo-
men of tlie latter, for a short time (about a week) ; then they shift for themselves
and develo() during the sunniier rather quickly, moulting repeatedly.'' In Septem-

" Compare Andrew's observatious on C. limoaus (1904, p. 190, ff. ) : he liistinguishes seven larval stages (each be
ginning with a monlt), from the hatching, end of May, to the middle of July, when a length of 29 mm. was reached.

ORTMANN: THE CRAWFISHES OF THE STATE OF PENNSYLVANIA 175

ber or October they have attained a Iriigth of from 40 to 50 mm., and the males
have assumed tlie first form. The females also are sexually mature, and copulation
takes place from September to November.'- During the winter no changes occur, and
in early spring they are in about the same condition as in the previous fall. In Ajiril
the females spawn, and it i.s remarkable that spawning takes place normally from
four to six months after copulation. The males generally go through the spririf/
moult in May, the females a little later in June. This brings up the size of this
generation to from 50 to 60 mm. Then the fall moult begins, lasting from August
to October, in which the specimens attain a size of over 60 mm. After the first sum-
mer only two moults, the one in spring and the other in fall, seem to take place.

At about this time, (October of the second year), the specimens are seventeen
months old. They go through a second copulating season, and through the follow-
ing winter, and again through the spring and summer with the same changes,
attaining by the two moults their maximum size of over 70 mm. in length. A
third copulating season follows, their age being now two years and five months. After
this they live until the next spring, when the old males die in April and May, and
the old females probably in June. This shows the life of the indivi<lual to be about
three years.'^

This seems to be the usual life-cycle of this species. But there are exceptions,
which are primarily due to the fact that in the first summer the growth of single
individuals may be quicker or slower. Whether slow growth, inducing late devel-
ment, influences the total length of life cannot be ascertained, but it must lead to
the result that some specimens are not sexually mature at the end of the fii-st sum-
mer, and that thus the fii-st copulation is postponed a whole year ; for copulation
seems to depend directly on the season, and takes place exclusively in fall, but never
in spring. Furthermore it may be that in single ca.'^es life is prolonged an additional
year, as for instance in exceptionally large individuals (about UO mm. long). But
we may safely assume that three years, or at the outside in exceptional cases four
yeai-s, is the duration of the life of this crawfish, and that an individual that lives
up to this age without having met with an accident has fulfilled its destiny and dies
a natural death.

A few additional remarks should be made with reference to egg-laying, moulting,
and copulation. The act of laying eggs is hard to observe, and I cannot improve
upon Andrews' observations on C limosns (|UoteMi al)ove. The process of moulting,

" Possibly be^iiinin^ at the end of AnKii.st and extending to .Innunty.

"Andrews ( 1901, p. 204) was able to trace ('. liiiwsuii only to the tliird siiniiuer, when the sole snrvitor o( his
material reached the size of 90 mm.

476 MEMOIRS OF THE CARNEGIE MUSEUM

is also rarely observed. The old skin splits on the back, between the carapace and
the abdomen, and the crawfish pulls itself out gradually, leaving the empty shell
intact. I have not made any observations on the increase of size at the moulting
time, in the case of this species. (But see below under C. diogenes, monovgaknsis,
and C. haiioni.) None of my specimens kept in captivity went through this process,
and those found in the field immediately after or during the act were too flabby to
be measured. Empty shells have been found now and then, but the individuals
belonging to these had then lost their identity. Possibly, as has been observed in
G. morumyalevsis, the old shells are eaten up.

The copulation resembles throughout that of ('. limosus, as described by Andrews
(1895, p. 867, and 1904, p. 166, Fig. 1, p. 168), and only a few remarks seem neces-
sary. The male with its claws takes hold of the claws of the female at the base of
the hand or the base of the fingers, and in shifting its position it often .seizes several
of the other pereiopods of the female. The other legs of the male are lying on the
sides of the carapace of the female. All the legs of the female are lying close
together on each side, directed forward. The male uses one of the fifth pereiopods,
sometimes the right, sometimes the left, to elevate the copulating organs, and this
leg is laid across the sternum, sticking out on the other side behind the fuurth perei-
opod. The use of the hooks is the same as in C. limosus.

After copulation the annulus of the female contains a " .spermal plug," as
described in C. limosus. Copulation takes place repeatedly between the same
couj^le, and one male may copulate in succession with several females, and one
female with several males. This has also been observed by Andrews (1895, p. 867)
in C. limosus, who says copulation "may be repeated by either animal with some
other."

2. Camharus propinquus and Cavibarus propinqmis .vanhorrii.

My observations on these two forms are fragmentary, but the dates at hand make
it certain that the seasonal history is identical with that of C. obscurns.

For C. propinquus I have only three observations dated in the summer ; the most
important being June 7, 1904 (( 'onneautville Station), when I collected a consider-
able number of this species. As in the case of C. obscurus no males of the first form
were found, and all males of the second form as well as females were of medium size,
between 47 and 60 nun. long. Specimens collected at the end of August, 1900, by
Dr. D. A. Atkinson at Presque Isle were in the same condition (no males of first
form), but there was with them a young female 27 mm. long, belonging apparently
to the generation born in June.

The rest of ray material was collected on October 4 and 5, 1901, in Erie C'ounty.

OKTMANN : THE CRAWFISJHES OF THE STATE OF PENNSYLVANIA 477

Here males of tlie first form were abundant, while those of the second form were
few and small (between 32 and 48 mm. long). The latter consequently all belonged to
the generation of that year. Some of them very likely would have changed into the
first form within a short time. The smallest male of the first form was 39 mm. long.

In addition I have seen specimens from Lake Erie, Lorain County, Ohio (Oberlin
Museum) collected May 1, 1892, which demonstrate the presence of males of the
first form in spring, and I have received from Mr. E. B. Williamson a couple col-
lected September 1, 1901, in Emmet County, Michigan, in the act of copulation.
The date is slightly ahead of my earliest date for this act in C. obsaims, but falls
into the same general season. All these dates perfectly agree with the rules laid
down for C. ohscurus.

Of C. propinquus sanborni I have collected material only in the early spring and
late summer. The specimens observed in spring (April 14 and 28, 1905), in the
Tuscarawas drainage, Ohio, correspond entirely to the spring condition of C. obscurm.
Generally they have a thick coat of dirt, showing that they have gone through the
winter without moulting. Most of the males are of the first form, but a few are of
the second form, and these have new shells. A large number of the females have
eggs. From Dr. Stei'ki I received a number of newly hatched young, 12-15 mm.
long, collected on June 18, 190(), at Dennison, Tuscarawas County, Ohio. Among
the specimens collected on August 28 and 29, 1905, in Wetzel and Pleasants
Counties, West Virginia, many males of the fii"st form were present, but also a con-
siderable number of the second form ; Ijesides, there were a number of small speci-
mens of the generation of that year. Among the material of this form from Oberlin,
collected September 28, 190.'i, the same was true, and thus in this form al.-<o the
known facts agree with what has been observed in the case of C. ubucurus.

3. Cambanis limosus.

This is the species on which Andrews (1895 and 1904) made his observations.
My own dates, which are supplemented by those collected by Mr. II. Cera and Mr.
W. R. McConnell, are comparatively few, but, as fiir as they go, show certiiin
discrepancies with Andrews' results, which need attentit)n and explanation.

The largest number of observations I possess are dated in the month of Septem-
ber, when I collected this species at numerous localities in eastern I'ennsylvania,
New Jersey, and eastern West Virginia in the yeare 18!)8, 1904, and 19U5. At this
time the condition of this species entirely corresponds to that of (.'. ohscitms. Males
of the first form are abundant and of all sizes. (Smallest, 37 mm. long, from Stony
Brook, Princeton, New Jersey, September 21, 1898, and 40 nun. long, from Cren-

478 MEMOIRS OF THE CARNEGIE MUSEUM

oble, Bucks County, Pennsylvania, September 20, 1904.) Males of the second form
are scarce, and most of them are of small size (between 28.5 and 40 mm. long).
Among the females also are many small individuals (as small as 25 mm. long).
These small specimens clearly belong to the youngest generation, born in the spring
of the year of capture.

Copulation was observed by Mr. H. Gera on September 4, 1905. I saw a
repeated copulation of the identical couple on September 10, 1905, and again, in
other specimens sent to me alive by Mr. Gera, on November 4, 1905. In addition
I have seen this species copulating in captivity in the Anatomical Laboratory
of Princeton University in January, 1899, (Ortmann, 1900, p. 1242). Thus the
copulating season is identical with that of C. ohscarus, and lasts from September
into the winter, possibly January.

C. limosiis goes through the winter,"^ and is found in spring in the same condi-
tion as in fall (April, 1899, at Princeton). In May I found females with eggs (May
9, 1905, Potomac River, (Jumberland, Maryland), and on May 30, 1898, I collected
females with young under the abdomen (Stony Bro(jk, Princeton, New Jersey).
Thus the spawning season seems to be identical witb that of C. ohscurus. During a
part of the summer males of the first form seem to be absent. I record that in July,
1904 (specimens collected by H. Gera in ( "amden County, New Jersey, without
exact date), no males of the first form were found. In a large set preserved in the
Academy of Natural Sciences of Philadelphia, collected by H. W. Fowler in tbe
Delaware River at Holmesburg, Philadelphia County, on July 4, 1899, all the males
are of the second form, and this although there are specimens in this set over
80 mm. long. Among the collections of W. R. McConnell there is a set of this
species taken on July 10, 1905, at Milesburg, Center ( "ounty, which contains two males
of the first form, with quite fresh shells. This date corresponds closely to the first
date (July 11), at which males of the first form of G. ohsctirus were observed.''

According to the above records it seems very likely that the seasonal history
agrees in every particular with that of C. obscums. The mating season in fall, the
spawning season in spring, and the absence of males of the first form in early
summer (June and part of July) agrees with what we know of G. obscurus. Com-
paring this with the account given by Andrews, we find the following differences.

"I collected specimens in January, 1899, in the Delaware- Raritan Canal, near Princeton, New Jersey. All
the males were of the first form Collecting was done by seining under the ice. The crawfishes were obtained in
water about four or five feet deep.

"Mr. McConnell collected a newly moulted male with a soft shell, of the first form, at Bloomsburg, Columbia
County, on July 19, !905, and during August he has several dates for these males : August 10 (Reading) ; August 18
(Marion) ; August 21 (Greenpark) ; August 22 (Landisburg).

ORTMANN : THE CKAWFJSHES OF THE STATE OF PENNSYLVANIA 479

Andrews (1904, p. 166) places the normal mating season in the months of February,
March, and the beginning of April, and says that there seems to be an autumnal
pairing (October, November) "in place of or in addition to " the spring pairing. I
believe, however, that the autumnal pairing is the normal one, which may be
extended through the winter. Indeed I have observed it in January, but only in
specimens kept in ca])tivity. Since Andrews' observations were made in the labora-
tory, it appears probable that the mating may be continued or repeated under exce])-
tional conditions such as are offered in captivity, but that this is not normal, in
C. obscurus I am positive that under natural conditions copulation does not take
place in March and April.

The time of spawning, as observed by Andrews (1904, p. 176) agrees well with
our records (end of March and April), also the time of hatching (/. c, p. 187), late
in ]\Iay.

As to sexual maturity, Andrews did not gather facts to show that females are
mature and oviposit at the end of the first year (1904, p. 206), although he observed
copulation at the end of the first summer. I observed, on November 4, 1905, copu-
lation taking place in specimens less tban 45 mm. long, and found females "in
berry " of the size of 50 and 45 mm. (Cumberland, May 9, 1905). Since the same
fact has been observed in the case of C. obscurus it is certain that males as well as
females are sexually mature at the end of the first summer, and that the sexual
union is effective, the females spawning the following spring. However, in such
small females the number of eggs is generally very small (fifty or less).

Thus it seems that C. Ilmosus agrees perfectly with ('. obscuru.'< in its life-history,
and that the only marked ditt'erence from Andrews' account concerns the mating
season. Tliis is however apparently due to the fact that Andrews' observations were
made in the laboratory. The explanation for this is very likely U) be sought in the
temperature conditions. The water used in tanks in laboratories has generally a
rather uniform temperature throughout the year, while umler natural conditions the
temperature of ponds, rivers, and streams varies considerably in summer and winter.
I made a few observations with reference to C. obscnriis. In .January, under the ice,
the water is near the freezing point, say about 35° F. ; on April 6, when females
were found spawning, the temperature of Thorn Creek, Butler County, was 45° F.
On May 1 the temperature of Grave Creek, Mai-shall County, West N'irginia, was
66° F. and spring moulttiig was going on. In midsummer I observed a temperature
of 82° F. in Bates Fork, Greene County, on July 21, and a temperature of 78° F. in
the Ohio, at Ambridge in Beaver County on August 24.

This gives a range of from about 35 to 80 during the vear, and 1 have no doubt

480 MEMOIRS OF THE CARNEGIE MUSEUM

that the nice restriction of certain periods in the seasonal history is primarily due to
differences of temperature. It is only natural that an equalizing of the temperature
must tend to efface the seasonal periods.

4. Camba ms diogenes.

According to my observations, which extend over the period from March 22 to
November 17, this species also agrees in the main features of its seasonal develop-
ment with C. obsctirus.

I have the following records for females with eggs: April 5, 1905 ; April 19,
1905; May 2, 1901; May 14, 1899, (collected by Atkinson, Graf, and Williamson) ;
May 21, 1906 ; May 22, 1905 ; May 27, 1904. On May 21, 1906, and June 2, 1905,
I found several females with newly hatched young under the abdomen. In no
other part of the year has this been observed, and thus the spawning and hatching
season is well fixed (April, May, and the beginning of June), and is found to be
identical with that of C. obscurus.

The number of eggs is considerably less than in the case of C. obscurus, and
generally falls considerably short of one hundred. The spawning does not take
place outside of the burrows, but inside of them, and this was most evident in a
female collected on April 6, 1905, (Renfrew, Butler County), in which the eggs were
quite fresh, witli traces of the "apron " still visible. This female was dug out of its
hole, as were all the rest with eggs or young ones.

After hatching the young remain a short time under the abdomen of the mother.
But soon they leave her, yet remain in the same hole. I have repeatedly foUnd
young specimens in the same hole with their mother, namely, on June 13, 1904 ;
June 15, 1905; July 6, 1905; July 19, 1905. The smallest were about 10 mm.
long. These young specimens generally occupy a separate part of the burrow, and
are often found near to and inside of the mouth of a closed chinmey. They remain
in the hole until they attain a length of 20 mm., which happens toward the end of
July. Then they leave the hole of the parent crawfish and begin to build their own
little holes and chimneys. I observed this on July 26, 1904, at Derry, Westmore-
land County, when I discovered a female 20.5 mm. long in a small hole of its own.
At the same date I found a larger one, 30.5 mm. long, which may have belonged to
the same generation. On August 4, 1901, at Francis Mine, near Burgettstown,
Washington (Jounty, I found numerous young specimens between 20 and 29.5 mm.
long, all in their own holes. On August 22, 1905, at Squaw Run, Allegheny County,
I discovered two young specimens 22 and 28 mm. long. On August 26, 1905, at
Baden, Beaver County, specimens 31.5 to 42 mm. long were found apparently under

ORTMANN: THE CRAWFISHES OF THE STATE OF PENNSYLVANIA 481

the same conditions. As late as September 5, 1904, (Smithfiekl, Fayette County),
and October 6, 1905, (Kittanning, Armstrong County), I found two very small speci-
mens (24 and 20.5 mm. long) in small holes. Never after July 19 have I found
young ones in the hole of the mother, so that it is quite sure that at the end of July
they invariabl}^ shift for themselves when they have attained a length of about 20
mm. The largest found in the hole with its mother was 18.5 mm. in length, on
July 19, 1905. Since young specimen? found in the same hole, apparently being
brothers and sisters, often have a different length (15 to 18.5 mm. in the case just
mentioned), and since, as said above, specimens of only 20.5 mm. in length are found
as late as October, the rule is established in the case of this species also that the in-
dividuals of the same litter grow up at a difierent rate.

With regard to the presence of males of the first form, the same conditions seem
to prevail as in the case of C. obscuriis. These males are frequent in spring. 1
found them at the following dates : March 23 ; April 2, 6, 15, 16, 24, 30 ; May 2, 3.
13, 14, 21, 22, 27, 29 ; June 2, 15. Then follows a gap of over a month to July 20.
Within this period I made observations upon the following dates: June 16, 18, 26.
27 ; July 6, 10. At none of these dates did 1 discover a male of the first form. It
is true that the material in this species is less abundant, a dozen specimens collected
on one day representing a rich luiul ; but it is nevertheless remarkable that during
the period just mentioned, in which particular pains were taken to get males of the
first form, none were secured. But after this they again appeared regularly, namely :
on July 20; August 7, 8, 22, 26; September 5, 7, 15, 19, 21 ; October 6, 9, 11, 18,
24 ; November 5. This makes it evident that in early summer (end of June and
beginning of July) there is a time when no males of the first form are present.

However, males of the second form are found at any time in the year as fre-
quently as those of the first form. In this respect C. d'wgcnes seems to differ from
C. obsciirus. This seems to be due to tlie fact that C. diogenes attains se.xual
maturity at a later age than C. obscuru.s and the river species in general. The
smallest male of the first form ever found met\sures 55 mm. in length (August i2.
1905, Montrose). It is hardly possible that this individual should belong to the
generation l)orn in June of the same year, since the latter are known to be at that
time about 30 or at the utmost 40 mm. long. We may assume tliat C (Uixjao.^,
like C. ohsmrm and C. limosus, may attain at the end of the first summer a length
of about 40 or 50 mm., but these individuals do not then assume tiie fii-st form as
the river species do. The same is true of the females. The smallest seen in copula-
tion (or associated with a male) was 63 mm. long, and the smallest female with
eggs was 62 mm. long.

482 MEMOIRS OF THE CARNEGIE MUSEUM

Young specimens less than 30 mm. long have not been found in spring, with
one exception, when a female of 25.5 mm. in length was found on May 27, 1904, at
Squaw Run. This, however, apparently was an exceptionally delayed individual
of the generation of the previous year. It was found under unusual conditions,
under a stone on the banks of the creek, evidently removed from its original habi-
tation by winter or spring floods. No additional specimens were seen in close
proximity.

I cannot say much in the case of C. diogenes in reference to the regular moult-
ing periods which were observed in C. obscunis to take place in spring and fall. I
have repeatedly found soft shells, and on April 24, 1904 (Nine-Mile Run, Pitt>-'-
burgh). at a place where a large colony of this species was present, I picked up
numerous cast-off claws,™ which would indicate an early spring moult. But these
claws may have accumulated during winter and spring. The rate of increase at a
moult was measured in one instance. A female, 52 mm. long, captured on April
6, 1905, was kept in captivity, and moulted on July 16. After this process it was
54 mm. long. This cannot be regarded as entirely normal, since the specimen was
kept under unfevorable and artificial conditions.

The copulating season of this species also falls in the autumn. I have only
twice observed a male and female in copulating attitude, but in both cases they let
go when disturbed. This was on November 5, 1904 (Nine-mile Run, Pittsburgh),
and on October 24, 1905 (Branchton, Butler County). The first couple was found
in water inside and near the mouth of a comparatively simple hole. The male was
70 mm., the female 81 mm. long. The second couple was found a little deeper, but
not over a foot, also in water. The male was 61 mm., the female 03 mm. long-
IMr. F. E. Kelly reports a similar observation made by him on November 14, 1904.
Besides on two other occasions I found males and females associated in couples in
the same hole. Three cases were observed on September 5, 1904, at Sniithfield,
Fayette County, and two cases on August 26, 1905, at Baden, Beaver County.
Since it is an absolute rule that under ordinary circumstances only one specimen
occupies a hole, these finds are .significant, and, inasmuch as in all these cases it
was always a male of the first form which was associated with a female of good size
(over 63 mm. long), it is evident that this association was connected with the mating
process. Whether the male visits the female, or vice versa, 1 do not know. In
every case the pair was easily captured, being lodged not far from the entrance of
the hole. In some of these cases I was struck by the simple character and small
depth of the barrow, and it may be that the couples dig out small, temporary holes

'j After moulting the shell is generally eateu up, with the exception of the bit; claws.

ORTMANN: THE CRAWFISHES OF THE STATE OF PENNSYLVANIA 483

for the mating time. This, however, needs further investigation, and possibly, if
found to be the case, may, nevertheless, not be the general rule.

In no other part of the year were similar observations made, and this fixes the
mating season for the months of August, September, October, and November," agree-
ing with what we have observed in the case of C. obscurus.

Thus we see that the sea.sonal C3'cle in the life of C. dinrjcnes corresponds closely
to that of the river-species. The only difference is in tlie time when sexual ma-
turity is reached, and it seems that in the case of C. diogenes this does not occur
earlier than at the end of the second summer. Whether this influences the dura-
tion of life is not known. Nevertheless the fact that this species frequently, or even
regularly, reaches a size superior to that of C. obsciirus, specimens of over 90 mm. in
length being quite often found, suggests that this crawfish may live more than three
years, possibly four or five.

The resemblance of the life-history of this burrowing form to that of the river
species is due, I believe, in large part to the similarity of conditions of temperature.
As has been stated, (.'. diogenes lives near stagnant water and swamps, in places
where there is generally not much fresh and cool water, although such places are
not strictly avoided, and where the temperature of the water is subject to consider-
able seasonal changes. In v>inter and spring the water in the holes is rather cool
(43° Fahr. on March 23, 1905, in Nine-Mile Run), while in midsummer it becomes
when stagnant, almost lukewarm.

The above observations are in part at variance witli those made by previous
writers on the same species. Girard (185"i, p. 88), near Washington, D. ('., found
females with eggs in March and April, which agrees with our dates, making allow-
ance for the difference of climate between Washington and western Pennsylvania.
Girard also notised the fact that as a rule only one individual was found in each
hole and mentions as an exception that in one burrow a male and a female were
found together. However, he neglects to tell the exact date of this find (his obser-
vations were chiefly made in spring). In one case, he says that a male was seen
walking over the surface of the ground, as he believes, in search of the female.
But in this instance also no date is given.

Tarr (1884, p. 127) never found male and female together (in May, near Wash-
ington), and always onl}' one individual in each burrow, and he never fountl .'spcci-
mens outside of the holes.'* lie further believes that the burrowing crawlishes re-

" It possibly extends further iuto the winter, a.sin the ca.se of tlie other species iliscussed.

" Although I have myself never seen a speciiucn of C. dwijrnn walking over ihe Kruiiiul, this must sometimes oc-
cur, for males and females must come tojjether in the mating; season, and the liohs do not communicate undrrcround.
.VccordiuK to William.'ion ( 1901, p. 12), C. diitgrne.i and ('. miiiwiignlriisiii are nocturnal, and that they come out of their
holes at night is shown by the fact that Mr. Khoada captured some of them in tniiw set out o\er night for roilents.

484 MEMOIRS OF THE CARNEGIE MUSEUM

treat to the streams in tlie winter, and in spring consti'uct holes tor the purpose of
rearing their 3'oung, and that impregnation takes place after the winter has passed.
These ideas are not supported by any evidence, and are, as we have seen above, in-
correct. His opinion that the same burrow is not occupied for more than one year
is also not supported by our observations.' The time of hatching of the eggs is given
as about the middle of May (p. ]2(S), which agrees with our dates. Faxon (1885a,
p. 74) reports that according to Mr. P. R. Uhler the female during the period of
incubation goes into pools, ditches, etc. This, however, is contrary to the observa-
tions of Girard, Tarr, and myself All these particulars refer to the eastern form of
C. diogenes, on the coastal plain, and it seems that with regard to the spawning sea-
son and the spawning habits this form agrees with that of western Pennsylvania,
alwaj^s considering the slight difference in climate which makes this season begin a
little earlier in the Atlantic lowlands.

The observations made on the western form show more marked differences.
Bundy (1877, p. 171) reports the discovery of a female Avith eggs nearly ready to
hatch, near Mechanicsburg, Henry County, Indiana, on January 1, 1875. Hay
(1896, p. 491) found that the breeding season in Indiana is in early spring, and ob-
served copulation on April 2, 1892. At this time the specimens leave their bur-
rows, and are frequentl}' found in open ditches and streams. The eggs were laid
from April 18 to April 30. He also repeatedly saw females with well grown young
in small streams. According to Harris (1890, p. 267) a female with eggs was found
in Kansas on May 3, 1891,"' apparently in an o}>en ditch, as is shown by the sub-
sequent sentences.

With the exception of Bundy's record these dates show April and May to be the
normal spawning season of the western form also. The observations of Hay and
Harris, that C. diogenes frequents open ditches in spring, and that it copulates in
spring, are, however, entirely at variance with the habits of this species in western
Pennsylvania. This is not the case here, and I have never seen sjiecimens outside
of their holes in spring. My observations began as early as March 23, at a time
when the frost was hardly out of the ground.

That this is also not the general rule in northern Indiana is shown b}' notes sent
to me by Mr. E. B. Williamson from Bluffton, Wells County, Indiana. Mr. ^^'il-
liamson writes to me : " As to C. diogenes congregating in ditches and the like in
spring I have no evidence here. The large males of diogenes can be expected in
almost every little stream. They move about on the bottom restlessly, not lying
concealed. Often the current catches them and they roll over and over, but they

'"Sic. Note the discrepancy between this date and the date of publication.

ORTMANN: THE CRAWFISHES OF THE STATE OF PENNSYLVANIA 485

always keep moving. Diogenes also wanders across country at this time, in day-
light as well as at night. I have found several crushed in wagon roads. Under
these circumstances I have yet to find a feraale." In another letter Mr. Williamson
says pertinently that the specimens taken by him in spring in open ditches are all
old males, "in which the death instinct had developed."

Thus it seems evident that the western form does not agree with the form found
in Pennsylvania in so far that in early spring the specimens seem to habitu-
ally leave their holes. Whether it is only old males when about to die (analogous
to what we observed in the case of C. obscurus) which wander about, or whether the
females with eggs also are found in open water, and furtlier, whether copulation
normally takes place in spring, are assumptions which remain to be proved. The
observations of Bundy, Hay, and Harris are surely correct, but it remains to be
ascertained whether they represent exceptional cases, or whether they are the rule.
Moreover it is not improbable that in the western form the seasonal cycle is slightly
different, since it lives under somewhat different surroundings. Hay (1896, p. 491)
reports that during the dry months of the summer C. diuyenes seems to lie at the
end of the burrow (which contains hardly any water) in a sort of a stupor. I never
observed anything like this in Pennsylvania, the holes of C. diogenes being always
well filled with water at the bottom, and the crawfishes being very lively.

That observations on the habits of this species should always be considered care-
fully with reference to all accompanying facts is evident from the following case :
Dr. D. A. Atkinson found a number of specimens on April 20, 1905, in open pools
near Westview, Allegheny County, Pennsylvania, in a region where this species is
abundant. These pools were in the course of an old, abandoned mill-race, which
dried out late in summer. All these specimens, seven in number, were young,
measuring from 33 to 5'2 mm. in length, and consequently belonging to the genera-
tion of the previous year. Now, bearing in mind the fact tlijvt the late summer and
fall of 1904 and also the winter of 1904-5 were characterize*l in our region by an
extreme lack of precipitation so that all streams were exceptionally low till the
middle of March, 1905, when a flood (March 20 to 25) restored the normal condi-
tions, it is very likely that this mill-race was dry in the summer and fall of 19(»4,
when these young specimens began to make their own burrows. They selected this
place as a favorable one, and remained there all through the winter, a few snialler
floods, one on .January 13 and another on March 9, not disturbing them, till tiie big
flood filled the mill-race again for a longer time, Such conditions, iiowever, do not
suit this species, and consequently the specimens came out of their holes, and were
found, at least for a time, in the open pools, till they had selected more convenient

486 MEMOIRS OF THE CARNEGIE MUSEUM

locations in the neighborhood. Thus this case must be regarded as exceptional, not
as a regular or normal episode in the life of tlie species.

5. Camharus harfoni and Camharus hartoni rohustus.

In all the species discussed so far we have f^und a regular seasonal period in the
life-history, marked chiefl\^ by a distinct mating-season in fall, a spawning-season in
spring, and a season in early summer when no males of the first form are present.
But it is entirely different in the case of C. hartoni. In this species none of these
seasons is recognizable.

As to the mating period, I have observations on only two dates. On May 27,

1904, I found a couple in copula in Squaw Run. Here I was able to make a clo.se
observation. The act of copulation is similar to that in the case of C. Ihnosus, as
described by Andrews (1901), but the male does not take hold of the anterior walk-
ing feet of the female with its chelre, and its second I pereiopods are clasped around
the carapace of the latter, lying in the cervical groove, and almost touching each
other on the back of the female. In this case it was the fifth pereiopod of the left
side, which was stretched across the sternum in order to elevate the copulatory
organs. The male of this couple was 67 mm. long, the female 73 mm. long. The
other observation occurred on October G, 1905, when I found two couples together
at Weskit, near Kittanning. The male of tlie first couple was 63.5 mm., the female
59 mm. long. In the other couple both male and female were 63 mm. long. Both
couples separated when captured, and thus I cannot give particulars.

These two dates are so far remote from each other that it seems hardl}^ probable
that they belong to one and the same breeding season. It is possible that one of
them is exceptional, but I have no means of deciding this. On the other liand, as
we shall see presently, spawning takes place at such different times of the year
that very likely the mating-season is also irregular.

Females with eggs have been found on the following dates : July 6, 1905 ; July
10, 1905 ; July 20, 1904 ; July 29, 1905 ; August 1, 1905 ; August 9, 1904 ; August 10,

1905. The number of eggs was between seven and one hundred and thirty-three,
the smallest number being found in the smallest individual, 59 mm. long. In ad-
dition I took a number of females with young under the al)domen. The following
records are at hand. At Princeton, New Jersey, in February, 1898. The exact
date is not recorded, but it was toward the end of the month. The length of the
female was 48 mm., the number of the young was ten.-" Further : March 31, 1905 ;

^"This number is unreliable, but represents as many as were secured. In some cases quite a number of theyouu}.'
dropped off wben tbe mother was captured.

OETMANN: THE CRAWFISHES OF THE STATE OF PENNSYLVANIA 487

length of mother 71 mm., ten young; August 18, 1904, length 59 mm., ninety-two
young; September, 20, 1905, two cases, one 53 mm., long, with thirty-nine 3'oung,
and another 55 mm. l(jng, with thirty-five young ; November 8, 1905, IS mm. long,
witli one hundred and eleven young; November 22, 1905, two cases, one 84 mm.
long, with seventy-five young, and another 67 mm. long, with sixty-eight young.

This extends the spawning season over tlie following months : February, March,
July, August, September to November. Since young were found in February and
November, these must have been in the egg-stage at least a month before they were
captured, and this would add .January and October. Thus we have only interrup-
tions in December and from April to June. The gap in December may easily be
filled, and be due only to the incompleteness of our investigations in winter, but
the gap in April, May, and June may be real.

If tliere is any spawning-season in C. bartoni it would cover nine months of the
year, from July to March. This, however, is entirely different from what we have
seen in the river species, where the spawning season falls exactly in the months
where no spawning has been odserved in C. bartoni. And besides, this gap may Ije
partly filled in C. barUriu. for I have found very young specimens (between K.) and
20 mm. long; the newly hatched young are 9 to 11 mm. long) on the following
dates: May 16, 1905 (13 to 14 mm.); May 25, 1905 (11 mm.); June 2, 1905 (about
17 mm.); June 12, 1905 (14 mm.); June 17, 1905 (15 mm.); August 22, 1905 (10
to 1 1 mm.).

Tlie conclusion is that very likely C. bartoni has no defined spawning-season,
but may spawn at any time of the year, and that accordingly the mating-season is
also not restricted to a particular part of the year. The latter is further sul)Stantiated
by the fact that males of the first form are found practically all the year round. I
have the following dates: March 21, 28; April 19; May 7, 9, 17. 21, 25, 27, 30;
June 2, 3, 6, 12, 13, 16, 23, 24; July 10, 12, 18, 26, 29; August 1, 10, 18, 22, 26;
September 11, 16, 20, 21, 30; October 5, 6, 10, 12, 17, 24, 31; November 8, 22;
December 25. The (jnly two months missing are January and February, when no
collecting was done. On the other hand males of the second form are also abund-
ant all the year round, and were found, with the exception of January and February,
in every month.

Under these circumstances it is impossible to say anything about the life-cycle
of the single individual, since different generations cannot be traced. Hut one
thing should be mentioned. Tlie males of this species do not seem to attain sexual
maturity as early as the river-species. The smallest male of thf lii-st form ever
found in eastern Penihsylvania is 49 mni. long, and in western Tennsylvania 50

488 MEMOIRS OF THE CARNEGIE MUSEUM

mm. long. The smallest female with eggs or young is from New Jersey (Princeton),
and is 48 mm. long. From the eastern part of our state I have seen none smaller
than 55 mm. long, and in the western part the minimum is 59 mm. in length.
This is considerably above tlie minimum size of sexually mature specimens of C.
obscurus and agrees better with C. diogcnes.

In one case I have been able to observe the increase in size which takes place
upon moulting. On Juh' 11, 1905, I found at Tionesta, Forest County, a female
in the act of shedding, and succeeded in keeping her alive till the new shell was
hard enough to be measured, 'i'he old shell was 32 mm. long, and the new one 36
mm. in length. In this case the crawfish withdrew from the old shell through a
crack that appeared on the dorsal side between the carapace and the abdomen.

We have seen above that the regular seasonal cycle observed in the river-species
is probably due to the regular and considerable changes of temperature taking place
in the rivers. C. hcuiuni lives in small streams, wliicli generally are much cooler in
summer than the larger ones, and this apparently explains the difference in the
seasonal history. The temperature conditions under which ('. haiioni is found, are
more uniform throughout the year, and consequently no regular seasonal periods
in the life are observed.

No previous observations on this species have been published, except William-
son's note (1899, p. 47), that this species was found with young under the abdomen
on March 28, 1899, at Columbus, Ohio. This lack of information is rather singular,
considering the extreme abundance of this form in the eastern part of the country.

Cambarus barfoni rohustus very likely is identical in its life-history with the
typical form. I have made observations at only a limited number of dates, but
they tend to show that there are no marked seasonal periods.

The following dates for the capture of males of the first form are at hand : May
27, 1904; July 11, 1905; August 22, 1905; September 18, 1900 (Atkinson collec-
tion); September 30, 1905; October 4, 1904; October G, 1904; November 14, 1903
(Mus. Oberlin). The smallest male of the first form measures 63 mm. in length.

Males of the second form were taken in the months of May, June, July, August,
September, and October. They were abundant in every case, considering the number
of specimens secured.

Copulation was never observed. A female with eggs was found on July 11,
1905, at Spartansburg, C-rawford County. It was 84 mm. long, and the number of
eggs was 228, more than twice the number of those usually observed in the typical
C. bartoni. Young specimens, less than 20 mm. long, were taken on May 27, 1904
(18 nmi.) ; and were numerous in a lot collected by Miss G. Kinzer on August 27,
1905 (9 to 16 mm.).

ORTMANN: THE CRAWFISHES OF THE STATE OF PENNSYLVANIA 489

I'or the months of December, January, February, March, and April, no records
are at hand.

6. Cambarus monongahmia and Can\barn,s carolinns.

The temperature conditions under which these two species are found are similar
to those observed in the case of C. barloni, and they are even more uniform, con-
sidering the fact that both are exclusively restricted to spring-water, avoiding even
small streams. In 1905 I took the following measurements of the temperature of
the water in the holes of C. monongalensis (May 16 at Morgantown, the rest at
Edgewood Park); March 18 (ground still frozen in places); 39° F. ; May 16, 58° F. ;
July 8, 63° F. ; August 18, 68° F. The range is considerably less than that given
for C. ohsairns (35° to 80° F., see above, p. 479). We consequently should expect a
similar irregularity in the seasonal history as in C. bartoni, differing markedly from
the third chimney-builder, C. diogene-a. This is indeed the case.

My observations are rather complete with reference to C. viunongalensis, covering
the time from March 18 to December 26. During no period within this time were
males of the second form absent or scarce, but males of the first form were also
almost regularly found ; the following are the dates for the latter : March 18 ; April
4, 21, 24 ; May 1, 6, 9, 16, 21, 24 ; June 3, 30 ; July 6, 8, 20, 24 ; August 7, 13, 18 ;
September 10; October 9, 10; November 8.

Copulation was not observed ; but in one case, May 6, 1904. (Fern Hollow), a
male of the first form and a female (55 and 72 mm. long respectively) were found
together in the same hole. The smallest male of the first form ever found was 53
mm. long.

Females with eggs were obtained on June 25, 1906 (<X T. Cruikshank): June
28, 1905, (three specimens) ; June 30, 1904, and July 20, 1905. These few obser-
vations would tend to restrict the spawning-season to the months of June and July,
but this conclusion is not admis.sible, since newly liorn young are found at various
other parts of the year. 1 have such (less than 20 mm. long) taken from the hole
of the mother, at the following dates: April 4. 19)5 (13 mm. long) : .Vpril 29, 1905
(18 mm. long); May 1, 1905 (17 to 20 mm. long): May 2, 1905(16 to 21 mm.
long); May 6, 1904(19 mm. long) ; June 11, 1901(19 to 20 mm. long): August
18, 1905(14 mm. long); September 24. 1898 (19 mm. long and above, colleeted by
Rhoads and Williamson); Octol)er 29, 1904 (19 mm. long). Tiiis e.\ tends the
spawning-season considi'r;il)ly. but it has the appearani-e of being interrupted
during the winter.

The smallest female with eggs is 58.5 nun. long. Tiie numlter of eggs is between
thirty-eight and seventy-nine, which is eonsideral)ly less than in the river species,
and also on the average slightly less than in C. bartoni and diugcnes.

490 MEMOIRS OF THE CARNEGIE MUSEUM

In this species the young of one litter seem hkewise to grow at a ditierent rate.
Thirteen young found with the vn(jther in the same hole on May 2, lUO-3, were
between 16 and 21 mm. long. Ten vouns; found on June 16, 1!)04, were from 20.5
to 32.5 mm. long. Twenty-two young, found on July 20. were from 22 to 27 mm.
long. Twenty-four specimens dug out with the mother l)y Rhoads and William-
son "^ on September 24, 1898, are from 19 to 29.5 mm. long.

Thus it seems that C. monoiigalensis agrees well with C. barfoni. No well-marked
spawning-season is present. At any rate the spawning-season extends over a very
large part of the year, and, correspondingly, no well-marked mating-season can be
distinguished. Males of the first form may be found at any time, and also males of
the second form. Se.xual maturity is delayed, males turning into the first form
comparatively late, and the females also are not mature before they have reached a
larger size than the river species. In all tliese respects, except sexual maturity, C.
monongalensis differs from C. diogenes.

There are further differences from C diogenes in the development of the young.
We have seen that young G. diogenes i-emain in the hole of the mother for some time
after they have left the abdomen of the latter. When hatched they are about 9 or
10 mm. long, and leave the mother very soon, since free individuals have been found
only 10 mm. long. When they have grown to about 20 mm. in length, they leave
the hole of the mother.

In C. monongalensis, however, they stay considerably longer in the hole of the
mother. The exact time camiut be ascertained, but we can draw conclusions from
their size. Free young specimens from 13 to 25 mm. in length are always found
with the mother. The smallest specimen which had begun to make a hole of its
own was 26 mm. long (August 7, 1905, Fern Hollow). Another was 29 nuH. long
(October 28, 1905, Edgewood Park). Specimens over 30 mm. long generally have
built their own burrows. But there are exceptions. As we have seen, young up to
32.5 mm. long have been found with the mother; and further, on July 24, 1905
(Deer Lick), I took out of one hole fifteen young, measuring from 27 to 33 mm. in
length, and out of another hole three young measuring 37, 39.5, and 40 mm. in
length. In these cases the mother was also in the hole. Although in the last two
cases conditions seem rather abnormal, it is certain that the young of C. mononga-
lensis remain longer in the hole of the mother than those of C. diogenes. While the
latter begin to shift for themselves when about 20 mm. long, young specimens of
C. monongalensis do not do so before they reach 25 or 30 mm. in length, and may
even postpone this step till they have attained a larger size (maximum 40 mm.).

*' Williamson ( 1901, p. 12) says that there were forty-seven young ones : only twenty-four are now in the collec-
tion of the Carnegie Museum (Cat. No. 74. 25). Possibly this discrepancy is due to a misprint.

ORTMANN: THE CRAWFISHES OF THE STATE OF PENNSYLVANIA 491

I once observed the change of a male from the second form to the first form.
The specimen was 58 mm. long, and was dug out of its hole on August 18, 1905, at
the type locality, Edgewood Park. It was kept in ajar in water, and had moulted
oil .\ugust 30. I had been away on an excursion on the two preceding days, but on
/Vugust 27 it had not yet shed. When the fact was discovered it had eaten the
larger part of its old shell, only the claws remaining, which were also eaten up sub-
sequently, all but the finger-tip.s, by September 4. The new shell measured 61 mm.
in length. When captured this specimen was of the second form. After moulting
it was of the first form.

On afcount of the irregular spawning season it is impossible to trace the life-his-
tory of one and the same individual, and consequently we cannot draw conclusions
as to the duration of life.

The few observations on C. carolinus entirely agree with those made on C.
monongalensiit.

Males of the second forms were found in May, June, July, August, and Sep-
tember. For males of the first form I have the following dates: May 17, 1905;
June 24, 1904 ; August 2, 1905 ; August 11, 1904 ; August 12, 1904 ; September 5,
1905; September 7, 1904 ; October 16, 1905. The smallest male of the first form
measures 56 mm. in length.

Two females with eggs were secured on July 12, 1904. One was 80 mm. long,
and had only three eggs ; the other was 77.5 mm. long, and had seven eggs. These
numbers seem strangely small, and apparently are not normal, for on August 1, 1905,
I found a female 69.5 mm. long, with twenty-two young under the abdomen. But
even this number is below the average of C. moiwiujulensls. While these cases seem
to indicate a spawning season in July, the finding of very young ones in the hole of
the mother at other dates considerably extends this period. I have found su'h on
May 17, 1905 (17 to 21 mm. long); June i:>, 1905 (14.5 to 21 mm. long); August
1, 1905 (18 to 23 mm. long) ; August 2, 1905 (28 mm. long) ; August 9, 1904 (17
to 25 mm. long) ; .\ugust I 1, 1904 (19 to 29 mm. long).

The largest young remaining with the mother were 29 mm. long, while the
smallest in a hole by itself was 30.5 mm. long. Thus the time of leaving the hole
of the mother is about the same as in ('. riKnioui/alnis-iii.

The above observations are not at all suftieient to show that C carolhuts agrees
entirely with C. monongale)m.'<, but since both species are alike in so many particu-
lars, morphological and ecological, and sinee the above dates do not show any di (Ter-
ences, we may safely assume that liie life-history of both species is similar.

The seasonal historv is rather well known in four of tlie speeies a imve discussed,

492 MEMOIRS OF THE CARNEGIE MUSEUM

C. obscurus, C. harfoni, C. vionongalensis, and C. diogenes. These are the species
found in Allegheny ( 'ounty, and they are most complete, since I had the best chance
to study them, three of them being found in the immediate vicinity of my residence
and the fourth (ohscnrus) within a few miles and within easy reacli.

We are able to distinguish two main tjq^es of life-history, which I should like to
call for convenience the ivarm water and the cool wafer ti/pes. C. obscurns and
diogenes represent the first, and agree with each other in having well marked mating-
and spawning-seasons, and in early summer a period when no males of the first form
are found. They differ, however, in the fact that in C. obscums sexual maturity is
reached, as a rule, at the end of the first summer, wliich does not seem to be the
case in C. diogenes. Of the other species, of which no complete series of dates are at
hand, the river-species, C. liynosus, C. i'>ropinquus, and C. propinquus sanborni, very
likely agree with C. obscxims, for the comparison of the dates does not reveal any
differences.

The coo! water type is represented by C. bartoni and C. monongalensis. Both are
characterized by the absence of well marked mating- and spawning-seasons. They
may be expected in any stage of development at any part of the year, even winter
making no exception. C. carolinas probably belongs also to this type, although the
observations are too scanty to jDOsitively establish the fact.

One thing in conclusion should be especially emphasized. The life-history and
the habits of different species of the genus Cambarus are by no means similar. On
the contrary they differ considerably, and the difterences may be accounted for pri-
marily by the different ecological conditions under which they live. Consequently
it is inadmissible to generalize from facts observed in one species only, and further
it is to be expected, if other species are studied, that additional types of life-history
will be discovered.

VI. ECONOMIC VALUE.

1. Popidar Inioirledge of Crawfishes.
The crawfishes of this state are generally well known t(j the population. They
are abundant and large enough to attract the attention even of the casual observer.
Rut it is chiefiy the small boy who is interested in them. Three popular names are
employed for them, crab, craijjish, and craivfislt. "Crab" obviously is a misnomer,
belonging originally to the marine Brachgura, but it is largely in use all over the
state, and chiefly so in the cities. The word " crayfish " is used the least. In my
experience I heard it mostly in the mouths of such people as had a certain amuunt
of schooling and had acquired some knowledge of natural history. This word is

ORTMANN : THE CRAWFISHES OF THE STATE OF PENNSYLVANIA 493

preferred by teachers generally, very likely in consequence of its use in one of the
standard works on these creatures (Huxley, "The Crayfish"). The third word,
" crawfish," is the proper American name. I found it commonly in use in the rural
communities where "crayfish " and " crab " were often entirely unknown. This is
chiefly the case in the southwestern section of the state and in West Virginia. In one
or two cases in Fayette and Somerset Counties I heard a distinction made between
"crab" and "crawfish." The former name was used for the river and brook
forms, C. obscunis and C. bartoni, the other for the chimney-buildei-s. All three
words go back to the same root. Old German krebia, from which is derived on the
one hand the modern German Krebs, and the English crab; on the other hand the
French icrevisse, the English crayfish, and the American crairfisli. The latter form,
being typically American, and Ijeing exclusively known to the natives of a large
part of the country (tlu' fanners), I have decided to use it in preference to the other
two forms.

In literature "crawfisli" was used by Say (1817), Harlan (1835), Hagen (1870),
Abbott (1873), Hay (1896). "Crayfish" was used by Abbott (1S84 and 1885),
Faxon (1885, 1890, 1898), Hay (1893, 1899), Andrews (1895, 1904), Shufeldt (1896),
Osburn and Williamson (1898), Harris (1900), Williamson (1901, 1905). Thus
" crawfish " has the priority.

Other names have been given incidentally, llafinesque (1817) calls C. Umosus
"mud lobster," (I heard this name once in Delaware County). Say (1817) and
Harlan (1835) call C. bartoni "freshwater lobster," and \A'illianison (1899) uses the
abbreviation "cray."

2. The use of crau'fishes as jood and bait.

Although well known, crawfishes are not much used as footl l)y the p<ipulation
of Pennsylvania; but this is generally the case in the United States. In some of
the larger cities of the United States they are found muri' or less regularly <>ii tiie
market (see Ortniann, 1900, p. 1260), C. linwsns being one of the species which is
principally used for food. I liavo, however, never heard that this is the case in our
own state, but it may be found in the markets of IMiiladelpiiia.*-'

Nevertheless crawfishes are eaten in this state, but not regularly. 1 have heard
sometimes from boys that they had tried them, but only in "sport." and only excep-
tionally have 1 met pei*sons who had eaten tliem repeatedly and were fond of tliem.
Generally, this source of food is unknown to the masses in tliis state. Yet a dish of
crawfishes is not to be despised. It is true, our species never attain the size of tiie

^'liafiuesqae (1817, p. i2) says of C. limosuo nt Philadelpliia, that il is "good to oat."

494 MEMOIRS OF THE CARNEGIE MUSEUM

highly esteemed European forms, but I know from my own experience that, as
regards quality, the former are not inferior to the latter. Young specimens (and
chiefly soft shells) may be fried in butter and eaten shell and all, while the abdom-
inal muscles of older ones, when boiled in water, are very good.

Of course, it is hard to create a taste for crawfishes among the mas.ses, Imt I do
believe that it would be worth while to try. Crawfishes are so abundant in certain
parts of the larger rivers, C. limosus in the Delaware, and C. ohscurns in the Ohio
drainage, that it is easy to get an}^ amount of them. It also would not be difficult
to raise them, for instance in ponds, and to supply the market regularly and judi-
ciously. And further, I do not see, why the "tails'' (abdomen) could not be used
for canning, exactly like the tails of shrimps and prawns.

Beyond this, crawfishes are used only as bait by fishermen. This use is quite
general, and crawfishes form an important part of the fisherman's outfit especially in
western Pennsylvania. They are most valuable in fishing for Black Bass {Microp-
terus), since these fishes seem to be very partial to this l)ait.

3. Crawfishes as scavengers. Their food. Their enemies.
The indirect economic value of crawfishes is best expressed by saying that they are
scavengers, as decapod crustaceans in general. They dispose effectively and quicklj^
of any decayed matter, animal or vegetable, coming within their reach. They also
eat living creatures. This was known previously. Abbott (1873, p. 83) calls them
(C limosus and hartuni) "omnivorous," and "scavengers," and says that they eat
water-weeds, and seize young Cyprinoid fishes. Andrews (1904, p. 175) fed C.
limostis in the laboratorv on raw and cooked meat, raw eggs, pieces of earthworms,
and on Chara and Hi/drodictijon. Williamson (1901, p. 12) reports that ('. laonon-
galeyisis was caught in traps baited with raisin and oatmeal. I used for my speci-
mens in the laboratory all kinds of meat, and since I am especially fond of smoked
sausage, I let them often partake of it when I had it for lunch. They also eat earth-
worms and green vegetable matter, for instance seedlings of several weeds (Galin-
soga, and Rumex acetoseUa), grass, and water- weeds ( ValUsneno). In nature they are
often found at carcasses and other animal refuse lying in the water. They eat in-
sects. For instance I have seen C. hartonl taking grasshoppers used as bait while
fishing for trout (Tub Mill Run, Ross Furnace, Westmoreland County). In the
case of the chimney-builders vegetable matter seems to be largely resorted to, not
only fresh plants, but also decaying vegetation being used. In digging them out of
their holes I repeatedly found masses of decaying leaves and the like lodged in some
side branch of the hole in such a position that they could not have fallen in acci-

ORTMANN : THE CRAWFISHES OF THE STATE OF PENNSYLVANIA 495

dentally, but must have been brought in by the crawfish. In one case (October 9,
1905, Nine-Mile Run), I found in a side-pocket of a hole of a female C. monoiigalen-
sis a number of ripe fruits of GraUpgux, about a handful, which under no circum-
stances could have fallen into the position where they were found. The hole was
under a large Crataegus bush.

Thus it seems that any vegetable or animal matter, either fresh, or decaying,
serves as food for crawfishes, and although some species may prefer certain classes of
food on account of taste or necessity, they all take readily to any kind, as is seen by
the fact that in captivity they eat everything that is offered to them without dis-
crimination. If nothing is given, the}' eat one another.

Crawfishes in turn serve as food for many animals, chiefly those which are
aquatic. Among mammals we know that raccoons hunt for them. As has been
mentioned above, birds eat them, and the kingfisher and other equatic birds do so
quite regularly. The report of Audubon, (see Ortman, 1900, p. 1250), that the White
Ibis captures the cliiinne3'-builders by throwing fragments of the chimney into the
hole, and watching for the crawfish to come up, does not seem strange to me. At
Ohiopyle I was told that a domesticated turkey kept upon the grounds of tlie hotel
had the habit of watching the holes of C. carolimis, and that frequently he captured
this species. I have myself seen this turkey standing motionless before a hole, but
I (lid not observe the actual capture. I do not entertain the slightest doubt that
this and other birds are able to catch crawfishes in this way, and do not think that
it is necessary to drop dirt into the hole, since the crawfish conies up frequently on
its own account, when it may be seized.

Crawfishes constitute an important part of the diet of certain snakes, more par-
ticularly of the water-snakes, Nairix sipedon and leheris. 1 have seen the latter dis-
gorge C. obscurus when captured. (See also Atkinson, Ann. Carn. Mus., I. 1901, p.
149, 150.) On two occasions I have found garter snakes, EuUenia sirlalh, in holes of
G. monongahnsis ; two specimens of this snake in one hole on Octol)er IH, 1904,
(Fern Hollow), and one snake in a hole on October 28, 1905, (Edgewood I'arkK
However, whether the snakes were after the crawfishes, or whether they simply were
using the holes for winter quarters, remains doubtful.

Professor H. A. Surface writes to me tiiat Criiiiloln-nnclin.'^ tillcglicitini.s-!.'< and Xcc-
turus maculosus are among the chief enemies of the crawfishes, and, indeed, these
two salamanders are generally found at places where crawfishes abound. (Comjiare
Eydeshymer, American Naturalist, XL. \'.H)C>. j). 128.)

They are, however, most valuable a.s food for the tish-fauna of our watei-s. As
has been mentioned above, crawfishes are good bait for certain fishe.-;, and it is very

496 MEMOIRS OF THE CARNEGIE MUSEUM

likely that many of our fresliwater fishes depend largely upon crawfishes fur iu;tri-
ment. It would be intei'esting to investigate how far this mutual correlation
between fishes and crawfishes holds good in our state. The presence of a river-
species in our western streams, and its absent-e in any drainage systems in the cen-
tral parts is very remarkable. Indeed C. harloni is found in rivers, but only occa-
sionally, and in small numbers. ]\Iy own observations are not sufficient to give an
approximate idea as to these relations, since I did not pay much attention to the
fish-fauna, and the latter has decidedly deteriorated, at least in quantity, and the
fish have become rather scarce in most of our streams. Possibly the decrease in the
number of fishes has caused an increase in the number of crawfishes.

4. Crawfishes as obnoxious creatures.

For the river-species hardly a point can be mentioned which would tend to show
that they are obnoxious to human interests, except the fact tliat they occasion-
ally capture young fishes. It is different with the burrowing species, which often
become troublesome. In regions where chimney-builders are abundant I have
repeatedly heard complaints about the chimneys, and chiefly so in the case of C.
carolinus in Somerset County, Pennsylvania, Garrett (bounty, Maryland, and Preston
County, West Virginia. Here the mud-piles may hamper farming operations by
interfering with the harvesting machines, clogging and ruining them. At Selbys-
port, Maryland, I was told that conditions were so bad that the farmers tried to
exterminate the crawfishes by throwing unslacked lime broadcast over the fields,
which operation was partly successful, the crawfishes coming out of their holes by
hundreds in a dying condition. I was told tliat this treatment, repeated several
times, had considerably reduced the numbers of the red crawfish in this neighbor-
hood. At no other place did I hear of attempts made to kill these crawfishes,
although farnaers were unanimous in denouncing them as a nuisance.

At a few places another complaint was made, namely, that the chimney-l)uilders
were cutting off and eating up sprouting crops. This was affirmed with reference
to G. carolinus at Reedsville, Preston County, West Virginia, where a farmer told
me that this species had cut off the largest part of a crop of buckwheat, so that
practically nothing was harvested. At Parson, Tucker County, West Virginia,
complaints were made that the same species had damaged sprouting C(irn : and at
New Martinsville, Wetzel County, West Virginia, I heard tliat G. diogcnes was
charged witli eating up all kinds of sprouting crops, corn and beans being especially
named.

I do not doubt that these complaints are justified, and that the Ijurrowing species

ORTMANN : THE CRAWFISHES OF THE STATE OF PENNSYLVANIA 497

actually eat and damage crops to a considerable degree. As I have observed, in
captivity C. monoiiijalensis and C. diogenes eat young plants, and they surely do so
when not in captivity, young sprouting corn, buckwheat, etc., being rather succulent
and attractive to them. If sown in a place where crawfishes abound these crops will
surely be attacked.

Tliis being the case, and besides the chimney's being also a nuisance, it might
be desirable to e.Kterminate the crawfishes in a given locality, or at any rate to
reduce their numbers. For tliis purpose unslacked lime, the means employed by
the farmers at Selbysport, might be used. But I am in no position to vouch for
the eflficiency of this remedy, having no personal experience (with the exception of
the one case mentioned above, p. 346). I simply report what was told me.

Another way might bo to drain the places where crawfishes are plentiful. But
this hardly will be as efficient a means as desired. Drainage only lowers the level
of the groundwater, and in the case of C. carolinus, which is the chief offender, we
know that it digs down sometimes over three feet to reach the gi'ound water. In
Rainier Park at Ohiopyle this species used to be very al)undant, but the draining
of the park has reduced its numbers. Still it is present there, and the chimneys
are thrown up all owr the lawn, where the holes must in places go down at least
three feet before reaching water. Thus, although a decrease in numbers may be
brought about by drainage, a complete extermination by this method must not be
expected.

Another form of damage done by chimney-buildei*s is known. They are reported
to burrow into and to do damage to the dams on ponds, reservoii-s. and rivers.
(The levees of the Mississippi. See Ortmann, 1900, p. 1262.) No instances of this
kind are known to me in Pennsylvania. In one case, at the reservoir of Mc( iee
Run, at Derry, Westmoreland County, I saw holes of C. diogenes not only along the
banks, but also in the dam. The specimens were all young, and the holes small,
since this reservoir has existed onl}' for a few years. But it would not be astonish-
ing if the crawfishes should gradually work deeper into the tlam, finally causing
serious damage.

VII. JU:.\RlN<i OF THE ABOVE STUDIES UN lllK TllEoUV V\'

EX'OLUTION.
Our observations on the Pennsylvania crawfishes, morphological, ecological, and
geographical, serve to illustrate certain phases of the process of evolution, and certain
theories propounded in connection with them. Naturally they do not elucidate
this process in its fullest scope. Thus I shall only pick out a few points upon which
my observations may have some bearing.

498 MEMOIRS OF THE CARNEGIE MUSEUM

1. TIte Mntation Theorij of De Vrics.

The latest fashion in evolution theories is the so-called " mutation theory "' of
De Vries (De Vries, 1905). It is much discussed at present, and the general trend
of opinion is that, although De Vries' idea of tlie origin of species may not hold
good in all cases, he certainly has demonstrated at least one way by which species
may be formed. It is generally maintained with emphasis that his experiments
are beyond doubt and that the facts demonstrated by him cannot be denied.

This indeed is the case, and it would be lamentable if any of the statements pre-
sented by De Vries as facts should prove to be unreliable. I am decidedly of the
opinion that the statements are correct, but I also hold that De Vries was not the
first to bring the facts forward. They belong to a class that was known long ago.
But furthermore, I believe that the conclusions drawn by De Vries from these
facts are entirely wrong.

I recently have devoted several articles to demonstrate this, and shall not again
go into detail here {see Science, May 11, August 17, and November 30, 1906).

However, I shall discuss here a special part of De Vries' theory, which concerns
the distinction he makes between " fluctuating variation " and " mutation." The
latter is said to be characterized by "sudden leaps,'' while the former is said to be
by " small steps." Although De \'ries sometimes does not lay much stress upon
this distinction (see Copeland, 1904, p. 421), this difference is often regarded as
paramount in his theory (see MacDougal, in Popular Science Monildjj, vol. 39,
1906, p. 207). And since De Vries believes that species are formed only by muta-
tion, it sliould be expected that the morphological differences betw^een existing
species should at least frequently exhibit signs of "sudden leaps." If such leaps
are observed in our species of Caviharus, this would tend to support this part of De
Vries' theory ; if not, the theory that mutations are alwaj's or generall}' marked l)y
discontinuity of variation, should be dropped.

2. Species, Varieties, and Variations among the Pennsjilvavia Crawfishes.

I have distinguished in the systematic part of tliis monograph seven species and
one variety among the Pennsylvania crawfishes. Besides I have discussed another
extralimital variety. This means that the characters distinguishing these forms are
different in their taxonomic value, and tlie reasons for thus estimating them should
be given.

The seven species of Pennsylvania belong to two subgenera, Faxonius and
Bartonius, which are distinguished by very sharp differences in the male copulatory

ORTMANN: THE CRAWFISHES OF THE STATE OF PENNSYLVANIA 499

Thu subgenus Faxonius is represented in our state by three species : ('. lirnusHs,
C. propiyiquus, and C. obscurus. Tlie firet is geographically, as well as niorplio-
logically, separated from the other two ; and here again it is the shape of the male
organs which serves as the chief distinguishing feature. Besides there are other
characters, such as the sliape and the spinosity of the carapace, which make it pos-
sible to recognize C. liraosus at a glance. N(j transitional forms being present, the
standing of C. limoms as a " good species " is beyond doubt.

It is different with C. propinquus and ohscurn,<i, and the e.xtralimital form (.'.
sanborni. These three resemble each other very closely, and it is hard, indeed
impossible, without close examination to distinguish them. They also live under
similar ecological conditions, and their ranges together form a unit, so that it is evi-
dent that they are closely allied genetically. The differences of C. obacurus from the
other two forms are furnished by the " shoulder " of the male organ and the tubercles
of the annulus of the female, together with the complete lack of the median keel of
the rostrum. Other differences, such as .sculpture and spinosity of the chelipeds,
are of secondary value and not entirely reliable. But it must be emphasized that
within the established range of C. obscurus, from Fish Creek in the .southern part of
the Panhandle of West Virginia to the upper Alleghany and the Genessee Rivers
in INIcKean and Potter counties, and from Cheat River at the West \'irginia state-
line, to the upper Shenango River in Crawford County this species is remarkably
uniform in the character mentioned. No specimens have been found within this
area which show the slightest tendency toward C. jiropiiiqinis.

Thus, with reference to this form, the postulate that a species should be sharply
and constantly separated from the coexisting allied forms is fulfilled (see Ortmann,
1896, p. 191) and accordingly I regard C. obscurus as a goorl species.

As regards C. sanborni, matters seem to be slightly different. It agrees in the
shape of the sexual organs with V. pro]>in<juus, and differs only from the latter in
the lack of a rostral keel and some minor features in the armature of the chelipeds.
In the lack of a rostral keel it approaches V. obscurus, l)ut always may be distin-
guished by the shape of the sexual organs. Its relation to C /mipiuquus wmaws
doubtful. ]\Iy ol)servations do not cover the region in which possible transitions
might be expected (northern and western ( )hio), and thus I must leave this question
open, and I follow Faxon in regarding ('. sanhorui as a variety of C i/ropiuiiuus.
But it should be possible to settle this question by proper investigation, and I wouhl
not be astonished if it should be finally discovered that ('. siuthnrui actually is a
good specie-s, sharply and constantly separated from C. propiutpius.

The subgenus Bartonius contains four species in Pennsylvania. One of them,

500 MEMOIES OF THE CARNEGIE MUSEUM

(7. bartoni, diflfers from the rest ecologically as well as niorphologieally. It is dis-
tinguished by a number of characters, and there is no possibility of morphologically
intermediate foiuus, so that C. bartoni not only is a good species, but also belongs to
a different section of the subgenus.

C. bartoni possesses in Penns3dvania a variety, C. bartoni robustvs, which, accord-
ing to my experience, is constant, and never runs into the typical form. It also
seems to occupy a slight]}' different territory, although oi'ten fuund associated with
the latter. These facts would justify us in regarding it as a good species. I have
not done so in the systematic part, since the facts at hand are too meagre to finally
decide this question. The range of (*. robiistas in Pennsylvania is only a small part
of the area occupied by this form, and in the states of Ohio, New York, and in
Canada, the conditions are entirely unknown. Furthermore a form similar to our
robtisttis, although, as it seems to me, not entirely agreeing with it, has been reported
from Virginia, Mar3dand, and Kentucky, and before particulars about the relation
of this form to C. bartoni and to our rolnitstns are known, we cannot judge as to the
taxonomic position of C. robustus. Therefoi'e I have refrained from modifying the
position hitherto assumed, that this form is a variety of C. bartoni.

The other species of the subgenus Bartonius in Pennsylvania are G. carolinus, C.
monongalensis, and C. diogenes. They belong to the t7io(/enes-section, and all three
are closely allied. C. carolinus and 'monongalensis are more nearly related to one
another than to C. diogenes. The latter apparently is a more advanced form.

C. carolinus and C. 'inonongalen.'<is are distinguished Ijy rather insignificant mor-
phological characters, discovered in the shape of the rostrum and the armature of
the chelipeds. But the difference in color is so striking that it is impossible to con-
found them in the field. Other cliaracteis also, although slight, hold good accord-
ing to my exj^erience, and I never have seen intermediate specimens. Moreover
the distribution of these two forms is ver}' characteristic, they being sharply sep-
arated topographically, and never being found associated at the same locality. Thus
all requirements leading us to pronounce them good species are met. Of course this
applies only to conditions in Pennsylvania, Maryland, and northern West Virginia ;
whether they are the same or different farther south remains to be seen.

C. diogenes is more sharply separated from the species just discussed, and there
is no possibility of mistaking this species, more particularly as the color is markedly
different. But the morphological characters are also very nicely expressed, so that
in a case of a red (albinistic) specimen of this species I was not a moment in douljt
that I had to deal with ('. diogenes, and not with 0. carolinus, although the latter
was found associated with this form at this particular locality (Dunbar). There is

ORTMANN: THE CRAWFISHES OF THE STATE OF PENNSYLVANIA 50 1

no douljl that C diogenes is a good species, and even when discovered in company
with C. monongalensis or C. carolinus we found no intermediate forms which might
render the identification uncertain.

As has been demonstrated above, there are two races of C. diogenes in Pennsyl-
vania, an eastern and a western. They never have been distinguished before, and
indeed are very simihir, so that it is hard to tell them apart. But I think I am
able to do so. The differences are very slight, but I never observed intermediate
forms, and their e.xistence is improbable, the ranges of the two races being widely
distant from each other. The constancy of the differential characters being the
only criterion of specific difference, while the amount of ditference is of no con-
sequence at all,^ we might regard the eastern form as a different species from
the western. This may prove to be the correct view, and then the eastern form
should be called C. diogenes (iirard, and the western possibly C. obesm Hagen.
I have not taken this course in the systematic part, since our knowledge of C. dio-
genes is by no means complete. I know only the conditions in this state, but the
eastern range of this species extends over large parts of the coastal plain, while the
western occupies a vast territory reaching to the Rocky Mountains and the ( Julf
It is also not impossible (although improbable) that the eastern and western areas
are connected somewhere, (in Virginia?). Before this question is finally settled, and
before we kn(jw more about the conditions under which C. diogenof occurs in the
extralimital parts, it is best to refrain from expressing a positive opinion. Never-
theless it is quite possible that there is a tendency in C. diogenes to split into varie-
ties and species. A variety has been distinguished in Louisiana.

We see that in certain forms my studies have led to a positive decision as to tiiuir
taxonomic position. In other cases my oljservations must be completed and sup-
plemented by additional evidence to be gathered in other parts of this country before
a final opinion can be reached. The fault is not with the material at IkiihI, l)Ut
with tlie insufficiency of our knowledge of the extralimital parts.

As to variation.^, tliat is to say, occasional aberrations from the typical form, we
have seen that such are extremely rare among the Pennsylvania crawfishes, and
have in most cases the character of freaks. Some of them, however, are interesting
from certain points of view.

No variations were discovered among one hundred and nineteen individuals of
C. limosm. With reference to C. propivijKus in Erie and Cmwford Counties, I have
pointed out that there is a certain amount of variation in the development of the

s^De Vries (1905, p. 127) talks of "an old rule in systenintic botany, tlint no form is to he constituted n sprcica
upon the basis of a single character." This rule is entirely unknown to me in botany as well as in roology.

502 MEMOIRS OF THE CARNEGIE MUSEUM

keel of the rostrum, and in that of tlie spines and the cavpopodite and raeropodite
of the cheHpeds, and we have also seen that there is sometimes a notch on the
anterior margin of the male organ. All these characters mark a certain inclination
toward C. obscurus which will be discussed below.

The six hundred and eighty-seven specimens of C. obsc2trus at hand are, as has
been seen above, very uniform in their cliaracters. A tendency has been observed
toward an increase of the spines of the meropodite of the cheliped in a direction
from the northeast toward the southwest within the range of this species. Here we
have apparently the first step toward the formation of a variety : a variation
becomes more frequent in the southwestern part of the range, possibly in conse-
quence of hereditary transmission, and begins to " breed true." But it is only the
beginning of it, the varying form not being found to the exclusion of the original,
and thus it remains " variation " only.

Other variations (mentioned p. 375 and 37G) are very likely due to injuries re-
ceived during life*^ and again others are of the character of freaks, namely the two
cases of apparent hermaphroditism. One of these is rather interesting (PI. XXXIX,
Fig. 7*^ and 7''). Here the male sexual organs do not at all correspond to the typical
form of this species, but approach in shape to that known in the ////losH.s-section. It
seems to me that we have to deal here with a case of atavism. The /imostts-section has
been regarded as the most primitive type of the subgenus Faxonius, on account of the
very slightly separated tips of the copulatory organs. The propinqims-sQoWou is next
to it, but here the tips are separated for a greater distance. It is quite probable
that the latter section descended directly from the* former, and it seems that in the
instance discussed the sexual organs have reverted to the original Umosus-iypQ, and
thus the assumption that the 'propinquiis-seciion is a descendant of the limusus-
section gains additional strength.

In the seven hundred and twenty-five specimens of C. bartoni we again have to
emphasize the great uniformity of the characters. The variations discussed are
rather insignificant, and consist chiefly in the shape of the rostrum and the size.
A single individual has been observed in which one lateral spine of the carapace
was present, apparently an atavistic feature. Othei' variations are of the hermaph-
roditic type.

No remarkable variations have been found in C. carolinus, and a few insignifi-

*• Variations due to injuries are most frequently observed in the case of regeneration of the chelipeds. I did
not mention them in the systematic part, since they are very common. If the claws are lost they are replaced by new
claws, which differ from the old ones not only in size, but also in shape. The fingers are proportionally longer, and the
palm proportionally shorter than in normal claws. This difference in shape remains even if the claws, after repeated
moults, again attain a good size. Regenerated claws may always be recognized by the short palm and long lingers.

ORTMANN: THE CRAWFISHES OF THE STATE OF PENNSYLVANIA 503

cant ones in C. monongaletms. The same is true of C. diogenes, leaving out of
account the differences between the eastern and western forms. The most important
variation is that of the width of the areola. In this there is a tendencj' toward
regional restriction, but it is not complete. The wide areola, being a more primi-
tive character, does not represent the variation, but the original condition, whioii is
retained only in a small part of the range and is even there not general. It is a
character that has a tendency to disappear and may be classed under atavism. A
case of albinism has been observed in C. diogenes.

The conclusions from the above observations are that in the Cambarus forms of
Pennsylvania the morphological characters are very constant, and that the varia-
tions observed are generally only slight, diverging very little from the typical condi-
tions. Anything that looks like a " mutation " in De Vries' sense is entirely un-
known, for the cases of hermaphroditism camiot be regarded as such, and the cases
of atavism and albinism do not fall under it, being clearly of a " retrograde " char-
acter (De Vries, 1905, p. 121 ci seq.).

Further, even between most of our well established species differences are so
slight that they cannot be regarded as representing " mutations," that is to say,
sudden leaps in a progressive direction (De Vries, /. c, p. 141 ). This is most evident
in tlio projnnquus-section, where the three forms, two of which at least must be re-
garded as species, are distinguished by such insignificant charactei-s that it is impo.s-
sible to talk of "leaps" or of "sudden changes." The same is true of the differ-
ences of C. carolinus, C. 'iiioiiongahnms, and C. diogeitci^, the amount of the differences,
although well marked, being very small, and the " gaps " between these species be-
ing infinitesimal. The only striking difference is in color, but before we know what
causes the appearance of various colors we cannot express any judgment on this
point.

Even in those species which are more isolated from the rest, the diOerences do
not amount to much. In C. bartoni the depression of the carapace and the width
of the areola differ only in the degree of the development from the same character
in the burrowing species. C. limostis isihe most strongly markeil species, but should
not be compared with the other river-species of Pennsylvania, but with its nearest
relations in southern Indiana (C. indianensi.t Hay), but then again the difference
is small and consists only of quantitative changes in tiie same features.

Thus the assumption of De Vries, that species have originated by sudden
leaps, does not find any support whatever in tlie conditions seen among the
crawfishes of Pennsylvania. On the contrary the close afllnity of most of them,
and the comparative insignificance of the specific characters, supports the view

504 MEMOIRS OF THE CARNEGIE MUSEUM

that these species have originated out of rather slight variations from tlie original
forms. If this is evident in so small a territory, further investigations onl}' can em-
phasize this, for additional material can onl}' bring these forms closer together. (See
Merriam, 1906, p. 257.)

3. Formation of Species hij Isolation, as Exemplified by the
Pennsjjlva nia Crawfishes

I have repeatedly maintained that the whole process of evolution in nature which
ends in the formation of "species," and which, consequently, may be called " origin
of species," is not subject to one single factor alone, such as " natural selection " or
"isolation" or " mutation" but that it is absolutely necessary that several factors
work together. (See Ortmann, 1896, p. 188 et seq.) Indeed none of these factors
is new, and they have been discussed by various writers, but generally too much
value has been attributed to one or the other of them to the detriment of the rest.
I have insisted, on the contrary, that four factors are equally' necessary to form
species, namely: 1, variation ; 2, inheritance; 3, natural selection; 4, separation
(/. c, p. 190).

Of these the last one, Sepcuration or Isolation, is the one which forms species. To
this is due the fact that the whole mass of organic beings to-day is divided up into
a large number of units, which we call " species." If it had never existed or acted
the process of evolution would have gone on nevertheless, but the organic world
would not consist of spied cs ; but since separation alwa3's has acted, species are pres-
ent. This does not imply that species should be everywhere well-marked. This
process is going on all the time, and in many cases it is not yet finished, and thus
it may be difficult sometimes to say whether a particular form is to be regarded as
a species or not ; but, as a rule, our inability to declare positively that a certain form
is a species is only due to the insufficienc}' of our knowledge.

Separation (or isolation) should not only be conceived of in its broad topograph-
ical and climatic aspect, but is, as I have always maintained, largely also ecological.
(See " bionomic separation," /. c, p. 190.)*' That it may occur under several forms
is amply demonstrated by the Pennsylvania crawfishes, and some f(,)rm or other of
isolation is evident in every case without exception. Both topographical and eco-
logical separation are recognizable in our material, while climatic separation is
not observed on account of the insignificant differences of climate in the region
investigated.

*=■ " Barriers" are not necessary. Merriam, 1906, p. 249, tliinlis tliat the existence of sharp barriers is necessary for
isolation; where such are absent lie prefers to use the term "divarication." Possibly the terra " habitudiual segrega-
tion," introduced by Gulick, 1905, p. 49, and 53 el seq. would be appropriate.

OUTMANN : THE CHAWFISHES OF THE STATE OF PENNSYLVANIA 505

(a) C. limosus.

It has been repeatedly emphasized above, as well as in a prev'ious paper, that
this species is well isolated morphologically and geographically. I have introduced
it as one of the examples for the rule that " morphologicall}' isolated species occupy
isolated stations" (Oi'tnian, 1905/;, [). 127), and also for the rule that "discon-
tinuity of distribution is a proof of antiquity '' {ibid.). Both rulosare beautifully illus-
trated by this species, particularly in contrast to the other rule that " closely allied-
species occupy neighboring areas." Thus not only the effect of isolation, as produc-
ing species, is evident in C. Ihnoms, l)ut it is'also seen that the degree of isolation
is in direct proportion to the sharpness of the expression of the specific characters.
C. limosus is geographically the most sharply isolated species of our crawfishes, its
area being several hundred miles distant from that of the most closely allied forms in
Indiana and Kentucky. Correspondingly it is also morphologically well marked.
being sharply distinguished from the other Pennsylvanian species, as well as from
species in the w( st wliicli are closely related to it. Isolation in this case is purely
topographical, since the ecological habits of C. indiimenais seem to be similar, (Hay.
l(Si)6, p. 495) ; though another allied form, C. sfoani, differs slightly ecologically,
(Faxon, 1885, p. 90).

(b) C. proinnquiis, C. froinnquus sanborni, C. obscuruK.

These three forms, as far as our present knowledge goes, are sharply separated
topographically, while they agree with each other ecologically, but the topograph-
ical boundaries between them are not everywhere uniformly sharp. In fact, the
ranges of these three forms are connected on the one side by the Ohio River, on the
other side by the basin of the Great Lakes.

As we have seen above, the ja-esent connection of these forms is a secondary
feature developed during the latter part of the Glacial Period, while anterior to this,
at the beginning of the Glacial epoch, diiferent conditions prevaileil, which were
different in turn from those of still earlier times. The history of these forms was
probably as follows. At the end of the Tertiary a form corresponding to these tliree
crawfishes existed in the drainage of the Erigan Uiver. Probably there was only a
single species resembling the present C. j)rnpin<f(u.-<. This .species livf(l in the Kri-
gan River, as well as in its southern tributaries, and there was no chance for it to
split u{) into different species, although variations may have occurred. When tin-
advancing ice of the Glacial Period covered the Krigan River and thus separated
the southern tril)utaries from each other, the latter formed lakes, and later, by over-
flow (or other means) they were connected again. Thus the present Ohio was
created. The temporary isolation of these rivei-s at the beginning of the (.ilacial

506 MEMOIRS OF THE CARNEGIE MUSEUM

epoch had its effect upon the crawfishes living in them. They developed into as
many species as there were rivers (three). Probably there was already in Tertiary
times a tendency within the Erigan drainage to form variations and even geograph-
ical varieties, but the fact that these for ms'( at least two of them) assumed the char-
acter of species is due to the physiographical features of the earlier Glacial Period.

After the Ohio was formed, and the connection between the areas of these
species was reestablished, thei-e must have been a tendency among tliem to mix
along the course of the Ohio River. How it was in the case of C. jiropinquus and
C. sanhorni we do not know. But I have investigated the facts in the case of C.
sanborni and (J. (jbscurus. Where they come together in the neighborhood of New
Martinsville, West Virginia, C. sanhorni shows no tendenc}' at all to go up the river,
no trace of it being found above New Martinsville. This apparently is due to the
greater difficulty of ascending the river and to contend with a species which is firmly
established there. On the other hand (\ ohscurus apparently has gone down the
river, and has invaded the original territory of (1 sanborni, but it has done so only
to a small extent. For, although it is easier to descend a liver, the fact that the
region invaded is occupied by another species with the same ecological habits must
make it rather difficult to oust the latter. Thus, although C. ohscurus has the advan-
tage over C. sanborni, being favored in its migration by the fact that it is here down-
stream, this advantage is only a slight one, and did not enable C. obscmms to occupy
any of the territory of C. sanborni to the exclusion of the latter. It is found here
associated with it, but its numbers are small, and the original form still prevails.

A curious fact, however, has been observed. I have pointed out (p. 367 and p.
4.34) that the specimens of C. sanborni captui-ed in Fishing Creek at New Martinsville
showed in certain characters an inclination toward C. obscurus. This suggests hybrid-
ization. Of course it is impossible to ascertain this positively without experiments,
but it seems that a crossing between these two forms is not altogether impossible,
for the shape of the sexual organs is very similar in both. They are generally very
closely allied, and further, their breeding seasons are identical, so that kyesame-
chania*" probably does not exist. This is further suggested by the conditions ob-
served in the Lake Erie drainage in Pennsylvania. Here C. lyropinquus and C.
obsc^irtis come together, and again we pointed out (p. 365) that C. propi7iquus in this
region has a tendency towards C. obscurus. In both cases hybridization would
easily explain matters.

** Impossibility of crossing, due to anj' cause, mechanical, physiological, or ecological, see Eimer, 1895, p. H.
Gulick (1905, p. 95) calls this " Impregnational Isolation." Under this head falls also Romanes' "physiological
isolation."

ORTMAXN : THE CRAWFISHES OF THE STATE OF PENNSYLVANIA 507

Even if it should be the case that C. ohsciinis may cross with C. propinquns and
C. propinquus sanborni, this does not invalidate its standing as a species, for we have
numerous examples in nature in which true species form hybrids.

Thus we see that these three species, the origin of which as species belongs to
the beginning of the Glacial time, have come together again ; but each seems to
remain in its orighial area, and where they come into actual contact the one species
is hardly able to oust the other. To a small degree hybridization seems to be p(js-
sible at the points of contact. The assumption that C. sanborni might be a hybrid
between C. propinquus and C. obscurus is rendered impossible by the exclusive
presence of C. sanborni all over its range (excepting Fishing Creek), without any
trace of the two other species.

It remains to consider the question what the relation of the specific characters
to isolation may be. We see that in the case of C. obscurus it is cliiefly tlie "shoulder"
of the male sexual organ which distinguishes this species. This shoulder is found
at a place where an external stimulus a(;ts upon this organ, namely, just where it
is touched by the fifth poreiopod in the act of copulation. A .similar shoulder is
found in many other .species of Cambarus of difierent groups and even sul)genera,
and thus it is highly probable that it is this external stimulus which induces the
development of this feature. But this does not afford us an explanation why this
shoulder did not develop in other species, especially in C. propinquus. At present
I am unable to answer this question. The fact remains that we have to deal witli
a specific character, wliicli is clearly due to an external stimulus,*' and I have
always held the opinion that every variation is invariably caused by a reaction of
the organism to some external influence. (See Ortmann, 1896, p. 188, and 1898,
p. 157.) But the view that acquired characters are transmissible is not fashionable,
although now admitted by its chief adversary, Weismann. In consequence of the
modern tendency to deny the effect of external causes upon variation, at any rate
to deny the possibility of the hereditary transmission of sucii variations, not much
attention has been paid to the mutual relations between external stimuli and the
reaction of the organism upon them. P>ut liere I think much room for investigation
is left. In the present case the reaction of the organism upon the external stimulus
caused by the contact of the fifth pereiopod with tlie sexual urgan is to form at the
point of contact a notch or angle (shoulder) on the sexual organ.

This reaction may be slightly advantagecnis, but it is not absolutely necessary,
for we see that there are many other species in which this reaction has not taken
place, even among the most closely allied forms, wliicli are nevertheless well off and

s'Under "pressure of the environraeDt," aa Slcrriam pata it (1906, p. 24-I).

508 MEMOIRS OF THE CARNEGIE MUSEUM

flourishing. In other words, the "selectional value" of this character is practically
at the zero-mark. This demonstrates again that the conception of " natural selec-
tion " as " selection of the fittest "' is incorrect. With regard to fitness there are many
characters which are entirely indifferent, and this is one of them. The absence or
presence of a rostral keel, and of tubercles in the case of the female annulus, the
other specific differences of these forms, Ijelong to the same class. We thus see that
natural selection has pla3'ed no part in the development of these characters of these
species. But tliis does not imply that selection has had nothing to do with the evo-
lution of these species, on the contrary this factor has always acted, and if these
characters had not been fit to survive, the species would not have been able to sur-
vive. Natural selection (in the modified sense, according to Pfeffer, see Ortmann,
1896, p. 176). resulted in the fact that the 'prcqnnquus-growp, such as it actually is,
is able to live and to fiourish, but it is not responsible for the splitting up of this
group into two or three species.

The latter fact is entirely due to isohition. In the present case the isolation was
in effect only during a short period in the past, but it was enough to differentiate
several species. At the present time there is a tendency to undo tliis effect. These
species are beginning to mingle again. But this process has not yet progressed far,
and for several reasons will very likely be slow in future. It is hard to say what
the outcome will be, whether we shall have a hybrid form, or whether one will sup-
press the others. C ohsctmis is the most advanced form, and also seems to be
slightly more vigorous than the others. Thus it may finally overrun them and
crowd them out, unless it is in turn conquered by a still more vigorous from, C.
rusticus, advancing from the southwest.

From the above discussion we see that whatever may have been the processes
of variation and of natural selection, or independently of what we may think
of the possibility of the inheritance of acquired characters, the fact that the
projyhiquns-gvoui:) has spHt up into species is solely due to isolation, which in this
case is strictly topographical. We have here three forms with identical ecological
habits, in which topographical isolation is evident, illustrating the rule that " closely
allied species occu^jy neighboring areas." (See Ortmann, 19056, p. 127, Jordan,
Science, Nov. 3, 1905, p. 546, and Merriam, 1906, p. 248, et scq.)

(c) C. hartoni.
This species is morphologically well isolated from the other Pennsylvanian
species, and also has peculiar ecological habits. Being found all over the state it
necessarily comes into contact with all the other species and is often found associated

OKTMANN : THE CKAWFISHES OF THE STATE OF PENNSYLVANIA 509

with them. This is preeminently the case with the river forms, C. limosus, C.
obscurus, and C. propinquus.

Here we have an instance in which at a given locaUty two species may be found
side by side. This, however, is due to secondary processes. Originally each of the
two species had a different center of radiation, and thus we again see the action of
isolation. The center (jf C. barloni lies in the mountains of the Appalachian s\'s-
tem ; the common center of C. limosics and the propiufjini.'i-gronp is in the central
basin of the Mississippi, and the special center of C. liiiKJim-s in the coastal plain,
and that of the propinquus-groni) in the Erigan and Lower Ohio drainage.

Nevertheless these species came together (see Ortmann, 1896, p. 186), but the
migration was in different directions, the river species coming up the rivers, while
C bartoni migrated down stream. Althoiigh living side by side there is no danger
of hybridisation, since their morphological differences are such that kyesame-
chania exists. The different shape of the sexual organs of C. bartoni from that in
the subgenus Faxonius precludes any idea of their being able to cross. Such cases
do not offer anything remarkable, since the occupation of and the association at the
same locality of different forms coming from different directions, and not being
closely allied, is the general rule in any ecological community {bwceno»is).

Conditions are slightly different in the cases where C. bartoni is found in close
proximity to the chimney-builders. Here there is closer affinity, but also it seems
here that these species are so far separated morphologically that kyesamechania
exists, although the shape of the copulatory organs is similar. Moreover, wherever
C. bartoni comes into contact with the burnjwing species it generally occupies situa-
tions slightly different from those preferred by the chimney-builders. It favore
running water in open streams, while the burrowers are fuund in holes at a certain
distance from the streams. Nevertheless, C. barloni is sometimes found in burrows
and in springs close to the one or the other of the burrowers (it is even found in the
holes of the latter, see p. 414), but in such cases we have again the same conditions
as above : different species coming from dillerent centei-s occupy the same
locality.

Yet as a rule C. bartoni occupies a different habitat from the burrowers. even if
found close to the latter. A fine illustration of this is in Nine-Mile Run. near
Pittsburgh. Here three species, ('.bartoni, C mononijaloi.tin. and C tlioijeur.-i are
found together upon a space hardly more than twenty feet square. The locality is
a pile of talus swept down into the valley of Nine-Mile Run by a small stream.
The stream comes through an insignificant ravine, and spreads out over the talus,
forming a kind of a delta, rendering the lower parts of the pile of talus nitlu-r

510 MEMOIRS OF THE CARNEGIE MUSEUM

swampy. At the upper end of the talus, in the outcrop of sandstone rock, and not
far (about fifteen feet) from the bed of the spring, is a copious spring, the water of
which runs directly into the clay and humus of the pile of talus, in a large part
underground. G. hartoni is found in the small stream under stones ; C. monon-
galensis is found at and immediately below the spring referred to ; and C. diogenes
is abundant all over the pile of talus down to the l;)ottom of the valley. At the
upper end of the pile of talus is the place where all three species come close to-
gether, but each is subject to different ecological conditions.

Similar conditions have been frequently observed, and we thus have here the
occupation of the same localities by closely allied species, which differ ecologically,
that is to say, fopographical isolation is not observed here, but the isolation is eco-
logical, and the differentiation of the chimney-builders from C. hartoni very likely
is connected with and largely due to the latter.

( d) C. carolinus and. G. monongalensis.

We have seen that these two species are very closely allied, but that the distin-
guishing characters are constant. Ecologically they are similar, so that hybridisa-
tion might occur when they come together. The latter case, however, has never
been observed, at least in Pennsylvania, Maryland, and northern West Virginia.
The western escarpment of the Chestnut Ridge forms a sharp boundary between
them. This case corresponds to that obsei-ved in the western river-species (prop-
iriquus-group). Two species identical in their ecological habits are separated topo-
graphically. But in this case the barrier separating them is of a different character.
What the essential feature of this barrier is, is hard to say. Chestnut Ridge in many
respects forms a boundary. Altitude seems to play a part, but whether it is para-
mount is doubtful. Absence of extensive deposits of clay on the western side of
this ridge on account of the destruction of the Old Tertiary base-level by subsequent
erosion, may also be of importance. Further studies in West Virginia surely will
lead to a solution of the question, but this much is certain, that these two species
again illustrate the rule that " closely allied species occupy neighboring areas," and
further they illustrate the ftict that specific differentiation is due to isolation, which
is topographical in this case.

What are the actual causes of the difference of the specific characters (color,
shape of rostrum, and sculpture of chelipeds), that is to say, what external influ-
ences are responsible for them is even more obscure, as it is in the case of the pro-
pinqxms-gr oup.

ORTMANN : THE CRAWFISHES OF THE STATE OF PENNSYLVANIA oil

(e) C. diogenes.

C. diogenes is sharply separated from the other chimney -buildei-s, Ijut resembles
them ecologically to a certain degree. In Pennsylvania it comes into contact with
them, but in tlic case of C. carolimis this has been observed only once, while it is
more frequent in the case of C. monongalensU However, intermediate forms have
never been observed, so that we must assume that kyesamechania prevents crossing.

In both cases, with reference to C. carolimis as well as C. vionongalemtis, it is to
be remarked that whenever one of these is found associated with C. diogenes it
is always only a contact, not a real mixing of both forms. Tiiis is best observed in
the case of C. vionongaleusis and C. diogenes. All over the range of C. viontrngalcnsis
in southwestern Pennsylvania C. diogenes is also found. But as has been stated
(p. 417 and 458), although they frequently dwell at the same localities they do not
occupy the identical locations, C. diogenes belonging to a lower level than C. vionmiga-
lensis. Thus we see again a separation, which isprirnarily expressed in the differenceof
altitude. Whether the latter is most important seems doubtful. It has been stated
that C. monongalcmis prefers spring-water, while C. diogenes lives mostly in swamps,
where the water is more or less stagnant and not so cool in summer. (Compare the
instance from Nine-Mile Run given above.) But, whatever may be the essential
feature which separates both species, it is clear that it is an ecological factor, and,
when these two species are found together, it is at a place where the ecological con-
ditions favorable to them come together.

That C. diogenes depends on different ecological laws from C. mouongalensis is
also evident from the fact that the former has, outside of Pennsylvania, an entirely
different range.

Thus we have here a case similar to that of C. bndoui when it associates with the
burrowing forms. Two allied species occupy (in Pennsylvania) almost the same ter-
ritory, and are not separated topographically, but their ecological .separation is evi-
dent, and very likely is connected with their specific diflerentiation.

In tlie two laces C. diogenes, the eastern and western, we again see tlie influence
of separation. .Vccording to our tlR'ory that the area of C. diogenes was a unit in
Preglacial times, and that it was separated by the advancing ice into an eastern and a
western section, which subsequently remained separate, we must expect, if isolation
effects specific differentiation, that the eastern and western form of (.'. diogenes should
show at least a tendency to develop dillerential characters of specific value. This is
indeed the case, as we have seen above (p. 401 et seq).

Isolation, or liabitudinal Segregation, as the factor forming species, is thus
clearl}' seen in every case discussed. Wo may condense the results obtained in the
following sentences.

512 MEMOIRS OF THE CARNEGIE MUSEUM

1 . The normal case is when two closely allied species, possessing identical or
nearly identical ecological habits occupy separated areas, which lie close together but
do not overlap. (Examples : j^i'opinquus-gronp ; C. carolinus and C. nionongalcnsis.)

2. Whenever allied species are found in one and the same locality (overlapping),
isolation becomes apparent in the following forms.

(a) The two species have different centers of origin, that is to say, they were
separated formerly, Init occupied the same territory subsequently. In this case, if
very closely allied, hybridization maybe possible (C. o/;sc»n(.s and C. sanborni at
New iNIartinsville, and C. ohscurus and C. propinquus in the Lake Erie drainage),
if no kyesamechania exists. If the latter is present, which always means that the
two species in question are less closely allied, the two species may actually live
side by side under identical conditions (C. hartoni and the river-species), or one may
conquer and suppress the other. No instances of the latter kind are known in
Pennsylvania, but may possibly occur in southwestern Ohio and in Indiana, between
C. nisticus and C. propinqims.

(b) If the centers of origin are more or less identical (absolute identity is hardly
possible), the two species always differ ecologically, and although li\ing at the
same localities, prefer different surroundings. In this case they are not so closely
associated, and they generally remain at a certain distance from one another,
although their general areas are overlapping. Under such conditions hybridisation
might occur, but it has not been observed in Pennsylvania, and the species existing
under such conditions are probably separated by kyesamechania. (Example : C.
diogenes and raonongalensis.)

Case (fl) and [h) may be combined, that is to sa}^, two species living together may
have different centers of origin and may be ecologically different. This is seen in
the example of G. hartoni and the burrowing species.

I believe that in every case where closely allied species overlap in parts of their
ranges a close investigaticm will reveal that one or the other of the above cases is
realized. Isolation is, in my opinion, a necessary factor in the differentiation of
species, and I do not think that a case ever will be discovered where two closely
allied species possess precisely the same distribution. But in order to ascertain this
a rnere superficial knowledge of the species in question and tlieir range is insuffi-
cient, and every case should be investigated as exactly as possible, in a manner
similar to the. above studies.

ORTMANN: THE CRAWFISHES OF THE STATE OF PENNSYLVANIA

513

1902. Abbe, C.

1873. Abbott, C. C.

1884. Abbott, C. C.

188r). Abbott, C.(".

1902. Adams, C. C.

1905. Adams, C. C.

1895. Andrews, E. A.

1904. Andrews, E. A.

1859. Bell, H.

1877. Bundy, ^V. F.

1882. BuNDV, W. F.

1883. Bundy, AY. F.

1903. Campbell, M. 11.

1880. Carll, J. F.

1904. Copelan]>, F. 15.

18X9. Davls, W. -M.

1844. De Kay, J. E.

1 905. De Vries, IT.

1895. Elmer, G. II. T.

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XXX, p. 127.
Natural History of Vermont, I, p. 170.
Drainage Modifications in Soutiieastern Ohio and Adjacent Parts

of West Virginia and Kentucivy. U. S. Gcol. Sun:, Profcsx.

Papers XIII.
List of the Described Species of Freslnvater Crustacea from

America Xorth of Me.\ico. Bull. III. Stale Lahoralon/, II, p. .365.
A Biological Examination of Lake Miciiigan in the Traverse Bay

Region. Bull. Mich. Fish. Comm., VI, p. lo.
Origin of tiie High Terrace Dejwsits of the Monongahela River.

Amer. Geolofjist, XVIII, p. 368.
Notes on Ohio Astacidfe. Seventh Ann. Rep. Ohio State Acad.,

p. 47.
The Crayfish of Allegheny County, Pa. Ann. Cam. Mus., I, p. 8.
Crayfishes from Kentucky. Ohio Natural., V, p. 310.
Tiie Northern Appalachians. (The Physiograj)liy of the L^nitcd

States. Nat. Geogr. May., p. 169.)

518 MEMOIRS OF THE CARNEGIE MUSEUM

EXPLANATION OF PLATES.

Plate A.

Fig. L Cambarns obscurus Hagen. Male of the first form, natural size. Collected by the

writer, Sept. 7, 1905, in the Alleghany River, Sandy Creek, Allegheny Cloiinty.
Fig. 2. Cambarns obscurus Hagen. Female, natural size. From same locality.
Fig. 3. Cambnrus diogenes Girard. Male of the first form, natural size. Collected by the

writer, Aug. 26, 1905, at Baden, Beaver County.
Fig. 4. Cambarns carolinus Erichson. Female, natural size. Collected by the writer, Sept. 5,
1905, at Rainier Park, Ohiopyle, Fayette County.

Plate B.
Fig. 1. Cambarus bartoni (Fabricius). Male of first form, natural size. Collected by the

writer, Aug. 7, 1905, in Fern Hollow, Pittsburgh.
Fig. 2. Cambarus barton! robustus (Girard). Female, natural size. Collected by Miss G.

Kinzer, Aug. 27, 1905, at Sixteen Mile Creek, Northeast, Erie County.
Fig. 3. Cambarus limosus (Rafincsque). Female, natural size. Collected by the writer, Sept.

10, 1905, in the Schuylkill Canal, Manayunk, Philadelphia County.
Fig. 4. Cambarus monongalensis Ortmann. Female, natural size. Collected by the writer,

Aug. 18, 1905, at Edgewood Park, Allegheny County.

Plate XXXIX.
Fig. 1. Cambarus bartoni (Fabricius). Rostrum. All figures ^.

la. Female, 70 mm. long. Collected by the writer, June 3, 1904, in North Versailles
Township, Allegheny County, opposite Stewart. Catalogue number 74.327. Shape
very broad, margins parallel. Not rare in western Pennsylvania.

lb. Female, 52 mm. long. Collected by the writer, Aug. 22, 1905, at Squaw Run, Alle-
gheny County. Catalogue number 74.626. Shape typical ; very frequent.

le. Male, first form, 63 mm. long. Collected by the writer, Sept. 16, 1904, at Valley
Forge, Chester County. Catalogue number 74.413. Shape typical, and character-
istic of eastern specimens, but also found in the west.

If?. Young male, second form, 34 mm. long. Collected by the writer, Aug. 22, 1905,
in Squaw Run, Allegheny County. Catalogue number 74.626. Usual shape in
young specimens.

le. Young female, 21 mm. long. Collected by the writer, June 25, 1904, in Jacob's
Creek, Laurelville, Fayette County. Catalogue number 74.356. Slightly longer
than usual, but not rare in young specimens.

1/. Male, first form, 78 mm. long. Collected by the writer, May 27, 1904, in Squaw Run,
Allegheny County. Catalogue number 74.320. Unusually short and strongly taper-
ing, with exceptionally thick margin.

OKTMANN: THE CRAWFISHES OF THE STATE OF PENNSYLVANIA 519

Fig. 2. Cambarus hartoni roiitiilu.s ((j'inu-d). Kostruni. -*.

2(1. Female, 89 mm. long. Collected by the writer Oct. 4, 1904, in Tiinplc Creek, Albion,

Erie County. Catalogue number 74.4.35. Normal sliape.
'Ih. Young female, 18 mm. long. Collected by Miss G. Kinzer, Aug. 27, 190.5, in Sixteen-
Mile Creek, Northeast, Erie County. Catalogue number 74.6.30. Nurmal shape in
young specimens.
Fio. .3. Cnmharus mrolinus Ericiison, iiostrum. J.

3«. Male, first form, 60 mm. long. Collected ijy the writer, Sept. o, 190."), at Oiiiopyie,

Fayette County. Catalogue number 74.640. Normal sliape.
'ib. Male, second Ibrm, 30 mm. long. Collected by the writer, .Jime 11, 1904, at Indian
Creek, Fayette County. Catalogue number 74.36.J. Shape exceptional. Most ex-
treme case as regards convergence of margins.
Fifi. 4. Cambdrns mono)if/alcusiti Ortman. Kostruni. ^.

4«. Male, first form, 6.3.5 nun. long. (Type.) Collected by the writer. May 21, 190.5, at

Fdgewood Park, Allegheny County. Catalogue number 74. .316. Normal shape.
46. Female, 73 mm. long. Collected by the writer, Oct. 12, 1904, at Hill, Westmorelan<l
County. Catalogue luunlier, 74.449. Shape unusually broad, and margins almost
parallel. Most extreme case in this direction, standing rather isolated.
Fig. 5. Cambanis limosus (Rafines(\ue). Left first pleopod of male, first form. |.

0(1. Inner view. Collected by the writer, Sept. 19, 1904, in Marcus Hook Creek, Mar-
cus Hook, Delaware County. Catalogue number 74. 12.3.
i)b. Posterior view of same.
Fig. 6. Ccmburn.^ prop!)iq>niK Girard. Left first pleopod of male. \.

6. Inner view, male, first form. Collected iiy the writer, Oct. 4, 1904, in Tiinple Creek,

Albion, Erie County. Catalogue number 74.^.39.
()/>. Inner view, male, second form. Collected i)y the writer, .lune 7, 1904, in a tributary
of Conneaut Creek, Conneautville Station, Crawford County. Catalogue numin'r
74.336.
Fig. 7. ( 'dmbdrn.'! obscnnts lliv^vu. Left first pleopod of male. *].

7(1. Inner view, male, first fi)rm. Collected by the writer, Aug. 24, I9gI, in the Ohio

River, Aml)ridge, Beaver Comity. Catalogue number 74.401 .
7/;. Posterior view of same (horny tip of outer part hidden behind inner iKirt).
7c. Inner view, male, second form. Collected by the writer, .Inue 24, 1901, in ilit- I^iyal-

lianna River, Cris]), Westmoreland County. Catalogue mnnluT 74. .352.
1(1. Inner view, hermaphroditic specimen (type of male, first form). Collected by Atkin-
son, Graf, and Williamson, May H, 1S99, in the Ohio River, Neville Island, Alle-
gheny County. Catalogue number 7.436. (See text, p. 376.)
7e. Posterior view of same.

ri20 MEMOIKS OF THE CAUNEGIE MUSEUM

Fig. 8. Cruiibiirua bartoiil (Fahriciiis). Inner view of left first pleopod of male, first form. ^.

Collected by the writer, Oct. 6, 1905, at Weskit, near Kittauning, Armstrong

County. Catalogue number 74.065.
Fig. 9. OuhImu-hx carolinun Erichson. Inner view of left first plenpod of male, first form. |.

Collected by tiie writer, Sept. 7, 1 1)04, at Dunbar, Fayette County. Catalogue

number 74.410.
Fig. 10. Cainharus monongdleiims Ortmann. Inner view of left first pleopod of male, first form

(cotype), \. Collected by the writer, Oct. 10, 1903, at Edgewood Park, Allegheny

County. Catalogue number 74.182.
Fig. 11. Qimbtinif! (linr/cncs Girard. Inner view of left first pleopod of male, first form. |.

Collected by tiie writer, September 5, 1904, at Sniithfield, Fayette County. Cata-
logue number 74.40(>.

Plate XL.

Fig. 1. ('(iin/tiirii.s ohsi'iii-Kx Ilagen. Upper view of right ciiela of a male, first fi)rm, 77 mm.

long, natural size. Collected by tlie writer, Sept. oO, 1905, in the Alleghany River,

Twelve-Mile Island, Allegiieny County. Catalogue number 74.663.
Fk;. 2. CambarKs bartoiu (Fabricius). Upper view of .right chela of a male, first form, 82 mm.

long, natural size. Collected by the writer, Nov. 22, 1905, in Fern Hollow, Pitts-
burgh, Allegheny County. Catalogue number 74.681.
Fig. 3. Cambaru,^ bartonl robustus (Girard). Upper view of right chela of a male, first form

98 mm. long, natural size. Collected by tiie writer, July 11, 1905, at Spartansburg

Crawford County. Catalogue number 74.596.
Fig. 4. Cdmbarus caroUnus Erichson. Upper view of right chela of a female, 77 mm. long,

natural size. Collected by the writer, Oct. 16, 1905, at Dunbar, Fayette County.

Catalogue number 74.669.
Fig. 5. t'dinbarun iiwnoiH/alcnsis Ortiiuinn. Upper view of right chela of female, 71 mm. long,

natural size. Collected l)y the writer at Edgewood Park, Allegheny County, April

4, 1905. Catalogue number 74.495.
Fk;. 6. C(unb<iriis dior/enes G'lravd. (Eastern form.) Upper view of right chela of a male, first

form, S3 mm. long, natural size. Collected by the writer, Sept. 2], 1905, at Pidley

Park, Delaware County. Catalogue number 74.654.
Fig. 7. Qintbdrux (Uogcnes Girard. (Western form.) Upper view of right chela of a male,

second form, 93 mm. long, natural size. Collected by the writer, April 15, 1905,

at Millvalle, Allegheny County. Catalogue number 74.507.
Fig. 8. Burrow of ('(iiiibarufi bartonl (Fabricius). In spring on hillside, west of Spruce Run,

Avalon, Allegheny County, opened by the writer, July 2, 1904.
8a. Side view (section) ; 86. Upper view, mp, pile of mud consisting of clay, sand, and

small stones; d, ditch; x, place where crawfisii, female, 52 mm. long, was found.

At X springwater was running into the hole in a strong flow, and running out through

the hole, over and past the pile of mud into a ditch.

OKTMANN : T}IK CKAVFISIIIS Or THE STATi: <>K I'KNN- VLV AMA 521

I'^ic. 9. Burrow of CmnhnruH foco/ZwiM Ericlison, lofntcd in a swampv place in stiH' vtllow t-Iay,
at Listie, Somerset County. Opened Ijv tlie writer Aufj. X'l, 1!HI4.
Il^f. Diagram of disposition of piles of mu<l seen from aliove. 9t. Section of hole along line
A-T). !»c. Se(!tion of hole along line A-Jl-C. A. Open chimney. /?. Closed
cliiinnev. I). Closed cliinmey, hole filletl up a good distance below surface of ground.
C. Open hole, witiiont pile of mud, situated un<ier tlie edge of a large flat stone («).
«•/, water level ; .r, i>Iaee where the crawfish (male, first form, (>\ mm. long) was found.

Pi-ATi; XLI.

Frci. 1. Burrow of C'amharn.s haiioni (F:\\mc'n\^). Located in the sand and gravel of the dry
bed of a small stream, Edgewood Park, Allegheny County. Opened i)y the writer,
Oct. 10, 190;]. mp, pile of mud, consisting of mud, sand, and gravel ; «, large slab
of stone, lying imbedded in sand and gravel ; W, water level (the stream was dn.- for
long stretches, only here and there pools of water were left); .r, place where crawfish
(female, 63.") mm. lung) was taken.

Frc;. 2. Burrow of CambnruH monoDf/tili'ima Ortmann. I^ocated in yellow clay (mi.ved with
humus), at a springy place on the bank of small stream, near Monongahela City,
Washington County. Dug out by the writer, June K), 1!M)-|.
2rt. Diagram of burrow and chimneys, seen from above; '2h, section of hole along line
A-B-C ; 2i; section of liolc along line C-l>-h'. A, hole opening laterally, with
one-sided iiile of mtid in front, kee])ing up the level of water ; /.' and J>, closed
chimneys ; C, open, large, and regular chimney ; irl, water level ; */, stream ; r, places
where the old female (mother, 05 mm. long), and ten young (20..') to ."52.") mm. long)
were found. Water, in a weak How, was rinining in at ^, and was running out at ,1.

Fig. .'j. Burrow of Camhanix monnuf/dlcuKis Ortmann. Loc-ated in yellow clay, at a springv
place on the hank of a small stream, Edgewood Park, .MIegheny ('onnty. Dug ont
i)y the writer, May !i, 1(101. Tlie burrow is of a tvpe similar to the one fignre<l in
Fig. 2, but less complex, n, hole opening laterally, with one-sideil pile of mud keep-
ing up the level of the water ; />, closed chimney ; i/7, water level ; nf, stream ; .r, ])lace
where the crawfish (female, Oo mm. long) was taken.

Fig. 4. Burrow of Camlmru.^ mouoiif/a/cnxix Ortmann. Located in black muck, at a springv
and swamj)y place at the bottom of the tipper |)art of Fern Hollow, Pittsburgh, Alle-
gheny County, opened by the writer, Oct. IS, UtO;}. Type of a hole in level ground,
with the water near the surface. No adults and only four young were found in this
hole, but ])Ossibly the hole had additional branches, which were not dis<'ovcFed, liie
high stage o(" the water anil its icy coldness rendering investig-.ition dillieult. Alxuit
l.r)0 m. from this hole another was opened, which contained a female C. rUognifn.
a, closed chimney ; h, one-sidi-d chimney in front of hole opening obliquely ; trl, wati-r
level ; .'•, places where young specimens (ll.o to l(!.."i mm. long) were found.

522 MEMOIRS OF THE CAKXEGIR MUSEUM

Fig. 5. Burrow of CKinlxtnix iJlcMjenes Giranl. Located in stiff blue clav,iii a ditch on a road-
side, IVine-iMiie Kun, Pittshnrgh, Allegheny County. Opened hy the writer, Nov.
o, lfM)4. The season had been very dry, and not much water was in the hole.
Pebbles were lying on the bottom of the hole, a, old chimney, leveled down by rain,
probably built in spring; h, fresh mud, brought up recently (beginning of fall
activity) ; wl, water level ; .r, place where the specimen (female, 77 mm. long) was
taken.

Fig. 6. Burrow of < 'din/tanis (Vukjciu-^ Girard. Located in yellow clay and humns, at a springy
and swampy place in woods on the side of a wagon road, upon which water was
standing (after a heavy thunder-shower on the previous day), at Squaw Iiuu, Alle-
gheny County. Dug out by the writer, May 27, lit04. <i, chimney, consisting of
yellow clay ; h, " stopper " in the mouth of the chimney, distinctly differing from the
chimney, the material being yellow clay mixed with blackish mud and leaf-mould ;
id, water level ; /•, road, with mud-puddle n|>on it ; .r, place where the crawfish (male,
first form, 711 mm. long) was found.

Fig. 7. Burrow of C'ctrnharus diofjenes Girard. Located in yellow and blue clay, on the l)order
of a swamj)y place, * dienley Farm, Pittsburgh, Allegheny County. After a sketch
furnished by Mr. !■ . E. Kelly, Nov. 14, 1904. sw, swamp; he, blue clay ; yc, yel-
low clay ; (', one-sided chimney, consisting of yellow clay (probably made iu spring
and summer) ; /(, new chimney, consisting of blue clay (fall activity, reclaiming of
old burrow at c) ; c, old burrow, filled in (during summer) with blue elav, taken or
washed in from near the mouth of the lower entrance (r() of burrow ; vl, water level ;
■c, place where the crawfish was taken.

Fig. 8. Burrow of Cambarns diogenea Girard. Located in blue and yellow clay on the bank
of a small stream, Schenley Farm, Pittsburg, Allegheny County. After a sketch
drawn l)y Mr. F. E. Kelly, Nov. 15, 1904. k, stream ; hr, blue clay ; //<•, yellow
clay ; a, new chimney, consisting of yellow clay, evidently coming from the newly dug
shaft going down vertically ; l>, upper end of ascending branch of hole, without open-
ing (possibly originally open, but sealed up, and the pile of mud overgrown and
obliterated by vegetation) ; vl, water level ; .r, place where the crawfish was taken.
The chimney at a shows fall activity, and the vertical shaft is being built by the
crawfish in order to get deeper down into the ground.

Pl.\te XLII.
Fig. 1. Preglacial Monongahela River, after Leverett (1902, j). 89, fig. 1).
Fig. 2. Present range of Cambanis obacurus Hagen and C. projnnquus Girard. (Licluding

variety Sdiiborni (Faxon)).
Fig. 3. Distribution of C'(Uiib<irus propinquuK Girard, propiuipms Konhonii (Faxon), and C.
obscurus Hagen.
(For further explanation, see legend on map, and text, p. 400-440).

oktmanx: the crawfishes of the state of pen's'^^ylvani a 0'2'.^

Pj,ate XLIII.
Map of Pennsylvania, showing i]istrii)iitional areas of crawfislics. (See Legend mi
map, and text, p. 460-466).

CARKEGI

MEMOIRS '^F THP -CARNEGIE MUSEUM, VOL. 11-

Memoirs Carnegie Museum, Vol. II.

Plate XXXIX.

MoupnoLOGic.vL Dktails (IF CtEXCs Cambanu.

Memoirs Carnegie Museum. Vol. II.

Plate XL

scale: 50 cm.

CiiKL.K OF Cambams. Fics. 1-7. Huiujows oi ('ianbtirii.<. I'ics. S-'.l.

Memoirs Carnegie Museum, Vol. II.

Plate XLI.

scale: SO o

m.

BrRROws OF Cambarus.

MEMOIRS OF THE CARNEGIE MUSEUM. VOL II

PLATE XU

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