Occasional Papers

Museum of Texas Tech University

NUMBER 204

02 February 2001

Effects of the Pecos River on the Geographic Distributions
OF Mammals in Western Texas

Clyde Jones and Deidre A. Parish

It has been demonstrated that some rivers in
North America are important physiographic features
with regard to the geographic distributions of mam¬
mals (Grinnell, 1914; Goldman, 1937; Davis, 1939;
Kelson, 1951; Findley and Anderson, 1956;
Hoffmeister, 1971). In addition, some nvers serv'e as
boundaries between distinctive ecological units and
biogeographic regions.

From the southern Rocky Mountains, the
Pecos River parallels the western edge of the Llano
Estacado in eastern New iMexico, In Texas, the Pecos
River flows for about 350 miles in a southeasterly di¬
rection from the New Mexico border to where it
confluences with the Rio Grande between Comstock
and Langtry in western Val Verde County at lake
Amistad (Fig. 1). The upper valley of the river
(Carlsbad-Iraan Subbasin) extends from the New
Mexico-Texas border southward to the vicinity of
McCamey and Iraan; the lower canyon (Iraan-Langtry
Subbasin) is entrenched into the Edwards-Stockton
Plateau (Leonard and Fry, 1962; Thomas, 1972).

The complex geologic history of the Pecos
River was controlled by a sequence of tectonic events
(Thomas, 1972). The upper portion of the river
(Carlsbad-lraan Subbasin) probably was formed in late
Tertiary and early Pleistocene times (Thomas, 1972).

The lower portion of the river (Iraan-Langtry Subbasin)
may have become entrenched into the Edwards-Stock¬
ton Plateau either during the Eocene (Thomas, 1972)
or in the early Pleistocene (Leonard and Fry, 1962).

The middle portion of the Pecos River and
associated valley was considered distinctive enough in
land form and climate, that recognition as a unique
physiographic unit was warranted (Fenneman, 1931).
The Pecos River has been regarded generally as the
southwestern boundary of the Great Plains (Graves
and Meinzer, 1999). The river also was considered as
the eastern boundaiy' of the Chihuahuan Desert in the
United States (Bryant, 1977; Wells, 1977; Schmidly,
1977a, 1977b; Johnson, 1979). In Texas, the Pecos
River w'as designated as the primary boundary between
the distinctive ecological units of the Trans-Pecos to
the west and the Edwards Plateau to the east (Schmidly,
1977a). Also, Schmidly (1983) designated the Pecos
River as the boundary between tw'o of the major mam¬
malian distributional regions (Trans-Pecos, Plains
Country) recognized in Texas. Because tlic Pecos River
is recognized as a boundary between diverse ecologi¬
cal regions, it may serve as either a biogeographic bar¬
rier or a filter zone for some of the unique mammalian
faunas associated with those regions in Texas (Hol¬
lander, et ah, 1990),

2

Occasional Papers, Mcselim of Texas Tech University

Figure 1. The Pecos River in Western Texas. The crossbar indicates the division between the upper valley (Carlsbad-
Iraan Subbasin) and the lower canyon (Iraan-Langtry Subbasin). From north to south, counties on the west side of the
river are Culberson, Reeves, Pecos, Terrell, and the western portion of Val Verde County. From north to south, counties
on the east side of the river are Loving, Ward, Crane, Upton, Crockett, and the eastern portion of Val Verde County.

Records of distributions of mammals in the
region of western Texas bisected by the Pecos River
were obtained from the literature (Schmidly, 1977a,
1991; Geonoways and Baker, 1979; Hall, 1981; Davis
and Schmidly, 1994; Stangletal, 1994; Yancey, 1997;
Goetze, 1998; Manning and Jones, 1998; and others).
Information associated with specimens housed in the
Collection of Recent Mammals in the Natural Science
Research Laboratory of the Museum of Texas Tech
University also was included in our examination of dis¬
tributions of mammals in the region.

Inasmuch as the Pecos River is the boimdaiy
between the Trans-Pecos area and the Edwards Pla¬
teau in Texas, species of extant, native mammals known
to occur in these major ecological regions are listed in
Table L The Trans-Pecos region has 97 species of
mammals; 79 species are known from the Edwards
Plateau. Of these, 67 species are known to occur in
both the Trans-Pecos area and on the Edwards Pla¬
teau. Twenty seven species occur in the Trans-Pecos
area and not on the Edwards Plateau; whereas, 11 spe¬
cies of mammals known from the Edwards Plateau

Jones and Parish— Effects of the Pecos River on Mammalian Distributions

3

Table 1. Extant, native mammals of the Trans-Pecos region and the Edwards Plateau of Texas. The presence ofspecies

of mammals is

the areas in designated by an X.

Mammals

Trans-Pecos Edwards

Plateau

Mammals

Trans-Pecos

Edwards

Plateau

Order Didelphimorphia
Family Didelphidae

Didelphis virginiana X

Order Itisectivora
Family Soncidae
Cryplods parva

N olio so rex crawfordi X

Family Talpidae

Scaiopus aquadciis X

Order Cbiroptera

Family Mprmoopidae

Mormoops megalophylla X

Family Phyllostomidae

Leptonycleris nivalis X

Diphylla ecaudota
Family Vespertilionidae

My Otis californicus X

My/ois ciliolabrum X

Myods htcifugus X

Myotis thysanodes X

Myods velifer X

Myotis volans X

Myods yurnariensis X

Lnsionycieris noctivngans X

Pipistrelhts hesperus X

Pipistrellus subjlavus X

Eptesicns fttscits X

Lashtrus biossevilU X

Lasinrus borealis X

Lasiurns cinereus X

Losiurus intermedius X

Lasiurns xanthinus X

Nycticeius humeratis X

Euderma maculadtm X

Plecolus townsendii X

Antrozous pollidus X

Family Molossidae

Tadarida brosiliensis X

Nyctinomops femorosaccus X

Nyctinomops macrotis X

Eumops perotis X

Order Xenarlhra

Family Dasypodidae

Dcisypus novemcinctus X

Order Lagomorpha
Family Leporidae

Sylvilagus aquaticus

SyJvilagus nudobonii X

Sylvilagus flon'danus X

Sylvilagus rohusius X

Lepus californicus X

Order Rodentia
Family Sciuridac

Tamias canipes X

Ammospermophiliis inlerpres X
Spermophilus mexiconus X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

Spermophilus variegatus X

Cynomys ludoviciamts X

Sciurus carolinensis
Sciurus niger X

Family Geomyidae

Thomomys boitae X

Geomys arenarius X

Ceomys bursanuS
Geomys lexensis

Cratogeomys cast an ops X

Family Heteromyidae

Perognathus Jlavescens X

Perognathus flavus X

Perognathus tnerriami X

Chaetodipiis hispidus X

Chaetodipus eremicus X

Chaeiodipus intermedius X

Chaetodipus nelsoni .X

Dipodomys merriami X

Dipodomys ordii X

Dipodomys spectabilis X

Family Castoridac

Castor canadensis X

Family Muridae

Reithrodontomys fulvescens X

Reiihrodontomys mega lot is X

Reithrodontomys monianus X

Peromyscus atn^aieri X

Peromyscus boylii X

Peromyscus nasuius X

Peromyscus eremicus X

Peromyscus leucopus X

Peromyscus maniculatus X

Peromyscus pectoralis X

Peromyscus truei X

Baiomys tnylori

Onychomys arenicola X

Onychomys leucogaster X

Sigmodon fulviventer X

Sigmodon hispidus X

Sigmodon ochrognathus X

Neotoma albigula X

Neoioma floridana X

Neotoma micropus X

Neoioma mexicana X

Microtus mexicanus X

Microtus pinetorum
Ondatra zibethicus X

Family Erethizontidae

Erethizon dorsatum X

Order Carnivora
Family Canidae

Canis latrans X

Vulpes macrotis X

Vulpes vulpes X

Urocyon cinereoargenteus X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

4

Occasional Papers, Museum of Texas Tech University

Table I. cont.

Mammals

Traf\s-Pecos

Edviiards

Plateau

Family Unidae

Units amen'eanus

X

Family Procyonidac

Bnssahscus asiuius

X

X

Procyon loior

X

X

narfea

X

X

Family Mustelidae

Musteia frennla

X

X

Afusfela vison

X

T(i\idert laxtts

X

X

Family Mephitidae

Spihgale gracilis

X

X

Mephitis macroura

X

Mephitis mephitis

X

X

Conepatus mesoleucus

X

X

Family Felidae

Leopardus pardalis

X

X

Lynx rufus

X

X

Puma concQlor

X

X

Order Ariiodaciyla

Family Tayassuidae

Pecan tajacu

X

X

Family Cervidac

Cenus elaphns

X

Odocolleus hemionits

X

Odocoiieiis virginianus

X

X

Family Antilacapridac

Antiheapra amcricana

X

X

are not recorded from the Trans-Pecos region. Some
species, such as Tamias canipes and Kficrottt^
mextcanus^ listed for the Trans-Pecos occur only in
the Guadalupe Mountains (Genoways et al., 1979). In
both areas, there are some extralimital records of dis¬
tributions of mammals, such as Myotis lucifugus in
the Trans-Pec os and Diphylla ecaudata on the Edwards
Plateau (Schmidly, 1991).

The differences in the richness of the mam¬
malian faunas of the two regions may be explained in
several ways. Topographic features and correspond¬
ing habitats are more diverse in the Trans-Pecos area
than those of the Edwards Plateau. For example, some
montane areas of the Trans-Pecos surrounded by
Chihuahuan Desert vegetation result in considerable
diversity of habitats. In general, areas with large ranges
in elevations tend to have greater species diversity than
those comprised of lower variability of elevations
(Williamson, 1981). Furthermore, Goeize( 1998) found
a rather strong affinity between the mammalian fauna

on the Edwards Plateau with those of the Llano
Estacado and the Rolling Plains regions of Texas. This
relationship was noticed by Schmidly (1983), who
suggested a combination of the Llano Estacado, Roll¬
ing Plains, and Edwards Plateau into a Plains Region.
In the Trans-Pecos region, mammalian faunas of the
montane areas have closer affinities to each other than
to the faunas of other areas (Genoways et al., 1979;
Starigl et al., 1994). Mammals of some of the low¬
land, Chihuahuan Desert areas in the Trans-Pecos re¬
gion have some levels of similarity to the mammalian
faunas of Chihuahua and Coahuiia, Mexico (Yancey,
1997). However, Chihuahua and Coahuiia are sepa¬
rated from the Trans-Pecos area by the Rio Grande,
which has been indicated as an important filler barrier
to the dispersal of Chihuahuan Desert mammals
(Schmidly, l977b,Yancey. 1997).

In order to examine more closely the importance
of the Pecos River with regard to geographic distribu¬
tions of mammals, we assembled information on the
presence of species of extant, native mammals known
to occur in the counties of Texas adjacent to the river
(Table 2). Some of this infomiation is similar to the
data given by Hollander et al. (1990); however, we
included all species of mammals known from the ar¬
eas adjacent to the river. Twelve species of mammals
occur in the counties just west of the Pecos River; 11
species have been recorded from the counties just east
of the over. Species of mammals known to occur in
at least some of the counties on both sides of the Pecos
River total 61 (Table 2). Of the 84 species of mam¬
mals listed in Table 2, the known disinbutional limits
of 23 species are at cither the west or east side of the
Pecos River.

Of the species of mammals with known geo¬
graphic ranges in the Trans-Pecos area west of the
Pecos River that occur also in the region east of the
river, 21 species are represented by different subspe¬
cies, at least in part, on the tw'o sides of the river (Table
3). It is important to note, however, that some spe¬
cies of mammals with broad distnbuiions in Texas are
known from the Trans-Pecos region based on single
specimens captured one lime at one locality. For ex¬
ample, for some information on the presence of
Scalopus aquaticus and Pipistrellus subjlavus in the
Trans-Pccos area, see the comments by Hollander et

Jones and Parish— Effects of the Pecos River on Mammalian Distributions

5

aL, (1990), Yancey et al. (1997), Yancey (1997), and
Maiming and Jones (1998). Distribution of subspe¬
cies of some mammals, such as Odocoileus
virginiams, may have been changed as a result of re¬
location or restocking. Delineation of geographic ranges
of subspecies of some mammals in the area is tenu¬
ous, at best, because of lack of appropriate informa¬
tion. The Holocene mammalian fauna of the region in
general and the Trans-Pecos in particular is in a dy¬
namic state (Stangl, 1994). For example, several taxa
of mammals unkno\Mi previously to occur in the Trans-
Pecos have been reported recently (Stangl, 1992);
Yancey et al., 1995; Bradley et al., 1999; Dowleret al.,
1999; Higginbotham et al., 1999; Jones et al, 1999).

There is general agreement that the present
system of the Pecos River became established in the
Pleistocene (Leonard and Fry, 1962; Thomas, 1972).
At that time, when the upper portion of the river was
becoming a southeasterly-heading, eroding stream and
the southern portion was entrenching, the Pecos River
may have been a major barrier to tlie dispersal of mam¬
mals (Leonard and Fry, 1962; Thomas, 1972). For
example, Hollander et al. (1990) suggested that the
river was a major factor during the Pleistocene in the
creation of a hiatus in the geographic distribution of
Scalopus aquaticiis in this area of Texas. The prob¬
able function of the Pecos River as a major barrier to
the dispersal of mammals is indicated, at least in part,
by the differences in the mammalian faunas on either
side of the river (Tables 1-3).

In historic time, during the early exploration
and settlement in the region, the Pecos River was a
major, flovving stream. Reports by early travelers in
the area described the river as “anywhere from 40 to
100 feet wide and four to 15 feet deep with a strong,
fast, turbid current” (Graves and Meinzer, 1999). The
lower canyon area of the river mostly was avoided in
the establisliment of travel and trade routes; travelers
relied on crossings of the Pecos River near the New

Mexico-Texas border (Jacobson and Nored, 1993;
Graves and Meinzer, 1999). For some additional de¬
tails on the hazards of crossing the Pecos River, as
well as some photographs and descriptions of the
crossings, see the work by Dearen (1996).

At the present time, the Pecos River is a rather
sluggish, highly mineralized stream, especially in the
upper portion; rapids are still present in the lower can¬
yon (Graves and Meinzer, 1999). The reduction of
flow of water in the river probably is the result of
development of rcser\'oirs, such as Red Bluff Lake
just below the New Mexico-Texas border, as well as
some additional impoundments upstream, interception
of the water for irrigation, changing land-use patterns,
and cyclic climatic events. Some changes in the veg¬
etation adjacent to the river have occurred, as well.
For example, although honey mesquite {Prosopis
glandulosa) and desertwillow {Chilopsis linearis) are
common trees along parts of the nver, the introduced
salt cedar (Tamarix sp,) is thick along the Pecos River
and is choking out the upper half of the river (Poweil,
1988).

The Pecos River is an important feature with
regard to the geographic distributions of mammals.
The lower canyon apparently has had more impact on
the geographic distributions of mammals in the area
than has the upper section of the nver. Based on the
analyses of the data available, it seems warranted to
suggest that the formation of the Pecos River was a
vicariance event that was important with regard to the
subsequent evolution and development of patterns of
distributions of the Recent mammals m western Texas.
As implied previously, the influence of the Pecos River
on geographic distributions of mammals seemingly has
diminished in historic times. Details of presence and
distributions of mammals, as well as relationships
among and between the mammals in the area in gen¬
eral and the Trans-Pecos in particular are imperfectly
known.

6

Occasional Papers, Museum of Texas Tech UiNivERSixy

Table!. Extant, native mammals known to occur in counties of Texas adjacent to the Pecos River. From north to south,
counties west of the river are Culberson, Reeves, Pecos, Terrell, and the western portion ofVal Verde County'. From
noi th to south, counties east of the river include Loving, Ward, Crane, Upton, Crockett, and eastern Val Verde County.
See Figure J Presence of taxa of mammals in the areas is designated by an X, Species marked with an * do not occur
either in the Trans-Pecos region or on the Edwards Plateau, but range into some of the aforementioned counties on
the east side of the Pecos River.

Pecos River

Mammals

West Side

East Side

Order Didelphimorphia
Family Didelphidae

Didelphis virginiana
Order Insectivora
Family Soricidae

Cryptotis parva
Notiosorex crawfordi
Order Chiroptera

Family Mormoopidae

Mormoops niegalophylla
Family Phyllostomidae
Leploiiycteris n walis
Diphyila ecaudala
Family Vcspcrtilionidae

Myotis califonuciis X

Afyotisciliolahmm X

Myotis thysanodes X

Myotis velifer

Myotis VO I a ns X

M) v tis yi tmanensis

Lasionycteris noctivagans X

Pipisirellus hesperus
Pipistrellus subflavus

Ep tes i cus fuse us X

Lasiurus borealis
La stunts cinereus
Plecoius lownsetidii
A ntrozous pallidus
Family Molossidae

Tadarida brasiltensis

Nyctinomops macrotis X

Eumops perotis X

Order Xenarthra

Family Dasypodidae

Dasypus novemchictus
Order Lagomorpha
Family Lepondae

Sylvilagiis auduboaii
Sylvilagus floridanus
Lepus Californians
Order Rodentia
Family Sciuridae

Ammosperrnoph ilus interpres
Sperniophilus me.xicanus
Spermophiliis spdosoma

X

X

X

X

X

X

Both Sides

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

Jones and Parish— Effects of the Pecos River on Mammalian Distributions

7

Table 2. coni

Pecos River

Mammals West Side East Side Both Sides

Spermophilns variegatus X

Cynomys ludovicianus X

Sciunisniger X

Family Geomyidac

Thomomys bottae X

Geoniys knoxjonesi* X

Ceomys personatus* X

Cratogeomys castanops X

Family Heteromyidae

Perognaih us fla vescens X

Perogn athusflavus X

Perogn alh us mer riant i X

Chaeiodipus hispidus X

Chaetodipus eretniciis X

Chaeiodipus intermedius X

Chaeiodipus nelsoni X

Dipodoniys merrianii X

Dipodoniys ordii X

Dipodomys sp ecta bii is X

Family Castoridae

Casio r ca n adensis X

Family Muridae

Reahrodontomys fulvescens X

Reithrodontomys megalotis X

Reithrodoniomys montanus X

Peromyscus attwateri X

Peromyscus boy Hi X

Peromyscus eremicus X

Peromyscus leucopus X

Peromyscus maniculaius X

Peromyscus nasutus X

Peromyscus pectoralis X

Baiomys taylori X

Onychomys areuicola ^

Onychoniys leucogaster X

Sigmodon hispidus X

Neoioma albigula ^

b/eoionia micropus X

Family Erethizontidae

Order Carnivora
Family Canidae

Cants iatrans X

Vulpes macrotis X

Vulpes vulpes X

Urocyon cinereoargenteus X

Family Procyonidae

Bassariscus astutus X

Procyo/i /oror X

8

Occasional Papers, Museum of Texas Tech University

Table 2 conL

Mammals

Pecos River

West Side East Side Both Sides

Family Mustelidae

Mustela frenata

X

Taxidea iaxus

X

Family Mephitidae

Spilogale gracilis

X

Mephitis macroura

X

Mephitis mephitis

X

Conepaius mesoieucus

X

Family Felidae

Lynx rufus

X

Puma concolor

X

Order Artiodactyla

Family Tayassuidae

Pecari tajocu

X

Family Cervidae

Odocoileus hemionus

X

Odocoileus virginianus

X

Family Antilocapridae

Antitocapra americann

X

Table 3. Extant, native mammals that

are represented by different subspecies on the two sides of the Pecos River.

Order Insectivora
Family Talpidae

Scnlopus aquaticus
Order ChiVoptcra

Family Vesperttlionldae
Pipistrellus sitbflavus
Order Lagomorpba
Family Leporidae

Sylvilagus auduboftii
Order Rodenti a
Family Sciundae

Spermophilus spilosoma
Spermophilus variegatus
Cynomys ludoviciamts
Family Geomyidae

r/iO/7jip;ny5 bottae
Cnilogeomys castatiops
Family Heteromyidae

Perognathus flavescens
Chaetodipus hispidus
Dipodomys ordii

Family Castoridae

Castor canadensis
Family Muridae

Reiihrdontomys fulvescens
Reithrodontomys ntonianus
Peromyscus leucopus
Peromyscus maniculalus
Neoloma albigida
NeoWina micropus
Onychomys leucogasler
Order Carnivora

Family Procyonidae
Procyon (otor
Order Artiodactyla
Family Cervidae

Odocoileus virginianus

Jones and Parish— Effects of the Pecos River on Mammalian Distribltions

9

Acknowledgments

We are grateful to R. Richard Monk for the
construction of the map in Fig.l. Larry L. Choate
and Robert S. DeBaca provided constructive comments
on a previous version of the manuscript. In addition,

we are appreciative of the many hours of discussions
with David J. Schmidly about the mammals of Texas
in general and the mammals of the Trans-Pecos re¬
gion in particular.

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Pp. 45-49 in Biological investigations in the
Guadalupe Mountains National Park, Texas (H.
H. Genoways and R. J. Baker, eds.). U.S,
Department of Interior, National Park Service,
Proceedings and Transactions Series, 4:xvii
+ 1-442.

Jones, C,, L. Hedges, and K. Bryan. 1999. The west¬
ern yellow bat, Lasiunis xanthinus (Chiroptera:
Vespcrtilionidae), from the Davis Mountains,
Texas. Texas Journal of Science, 51:267-269.

Kelson, K.R. 1951. Speciation of rodents of the Colo¬
rado River drainage. University of Utah Bio¬
logical Series, 11 :vii +125.

Leonard, A. B., and J. C. Frye. 1962. Pleistocene
molluscan faunas and physiographic history
of Pecos Valley in Texas. University of Texas
Bureau of Economic Geology, Report and In¬
ventory, 45:1-42.

Manning, R. W., and C. Jones. 1998. Annotated
checklist of Recent land mammals of Texas,
1998. Occasional Papers, Museum of Texas
Tech University, 182:1-19.

Powell, A. M. 1988. Trees & shrubs of Trans-Pecos
Texas including Big Bend and Guadalupe
Mountains National Parks. Big Bend Natural
History Association, Big Bend, Texas, 536 pp,

Schmidly, D. J. 1977a. The mammals of Trans-Pecos
Texas including Big Bend National Park and
Guadalupe Mountains National Park. Texas
A&M University Press, College Station, xiii +
1-225.

Schmidly, D. J. 1977b. Factors governing the distn-
bution of mammals in the Chihuahuan Desert
region. Pp. 163-192 in Transactions of the
symposium on the biological resources of the
Chihuahuan Desert region, United Slates and
Mexico (R. H. Wauer and D. H. Riskind, eds).
U.S. Department of Interior, National Park
Service, Proceedings and Transactions Series,
3:xxii + 1-658.

Sclimidly, D. J. 1983. Texas mammals east of the
Balcones Fault Zone. Texas A&M University
Press, College Station, xvii + 1-400.

Schmidly, D. J. 1991. The bats of Texas. Texas
A&M University Press, College Station, xviii
+ 1-188.

Siangl, F. B., Jr. 1992. A new subspecies of the
tawny-bellied cotton rat, Sigmodon fulviventer,
from Trans-Pecos Texas. Occasional Papers,
Museum of Te.xas Tech University, 145:1-4.

Stangl, F. B., Jr., W. W. Dalquest, and R. R. Hollander.

1994. Evolution of a desert mammalian fauna:
a 10,000-year history of mammals from
Culberson and Jeff Davis counties, Trans-
Pecos Texas. Midwestern State University
Press, Wichita Falls, Texas, xix + 1-264.

Thomas, R. G. 1972. The geomorphic evolution of
the Pecos River system. Baylor Geological
Studies Bulletin, 22:1-40.

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Chihuahuan Desert less than 11,500 years ago.
Pp. 67-83 in Transactions of the symposium
on the biological resources of the Chihuahuan
Desert region, United States and Mexico (R.
H. Wauer and R. H, Riskind, eds.). U.S. De¬
partment of Interior, National Park Service,
Proceedings and Transactions Series, 3:xxii
+ 1-658.

Williamson, M. 1981. Island populations. Oxford
University Press, Oxford, England, xi + 1-
268.

Yancey, F. D., II. 1997. The mammals of Big Bend
Ranch State Park, Texas. Special Publications,
Museum of Texas Tech University, 39:1-210.

Jones and Parish— Effects of the Pecos River on Mammalian Distributions

Yancey, F. D., II, C. Jones, and R. W. Manning. 1995.
The eastern pipistrelle, Pipistrellus subflavus
(Chiroptera: Vespertilionidae), from the Big
Bend region of Texas. Texas Journal of Sci¬
ence, 47:229-231.

Addresses of authors:

Clyde Jones
Texas Tech University

Department of Biological Sciences and the Museum

Lubbock. TX 79409-3/9!

e-mail: cjones@packrat. musm.ttu. edu

Deidre a. Parish
Texas Tech University

Department of Biological Sciences and the Museum
Lubbock, TX 79409-3/9!
e-mail: dparish@,ttu.edu

Publications of the Museum of Texas Tech University'

It was through the efforts of Horn Professor J Knox Jones, as director of Academic Publications, that
Texas Tech University initiated several publications series including the Occasional Papers of the Museum. This
and future editions in the series are a memorial to his dedication to excellence in academic publications. Profes¬
sor Jones enjoyed editing scientific publications and served the scientific community as an editor for the Journal
of Mammalogy, Evolution, The Texas Journal of Science, Occasional Papers of the Museum, and Special
Publications of the Museum. It is with special fondness that we remember Dr. J Knox Jones.

Institutional subscriptions are available through the Museum of Texas Tech University, attn: NSRL Publica¬
tions Secretary, Box 43191, Lubbock, TX 79409-3191. Individuals may also purchase separate numbers of the
Occasional Papers directly from the Museum of Texas Tech University.

ISSN 0149-175X

Museum of Texas Tech University, LubbocK TX 79409-3191