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MAY 1 2 1970
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SMITHSONIAN CONTRIBUTIONS TO PALEOBIOLOGY • 1970 NUMBER 4
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S. Dillon Ripley
Secretary
Smithsonian Institution
SMITHSONIAN CONTRIBUTIONS TO
PALEOBIOLOGY
NUMBER 4
Richard Cifelli
and Roberta K. Smith
Distribution of
Planktonic Foraminifera
in the Vicinity of the
North Atlantic Current
ISSUED
APR 18 '870
SMITHSONIAN INSTITUTION PRESS
CITY OF WASHINGTON
ABSTRACT
Cifelli, Richard, and Roberta K. Smith. Distribution of Planktonic Foraminifera
in the Vicinity of the North Atlantic Current. Smithsonian Contributions to Paleo¬
biology, 4:1-52. 1970.—Planktonic Foraminifera collected from the vicinity of
the North Atlantic Current and the Gulf Stream during late winter-early spring
and fall of 1964 are described and their distributions are recorded. Variations in faunal
composition seem to be related largely to water regime dynamics and seasonal cycle.
Among the fall collections, three distinctive assemblages can be recognized: a western
group in the vicinity of the Gulf Stream, containing predominantly Sargasso Sea-Gulf
Stream species dominated by Globigerinoides ruber; a northern group, dominated by
Globigerina quinqueloba egelida, new subspecies, reflecting the influence of cold,
northern waters adjacent to the North Atlantic Current; and an eastern group,
dominated by Globigerina incompta, apparently developed within the limits of the
North Atlantic Current. The last group seemingly represents an anomaly, as North
Atlantic Current surface temperatures were relatively high at the time of collection,
and dominance of a warm-water form, such as Globigerinoides ruber, might have been
expected. The anomaly suggests that the North Atlantic Current is a partially closed
gyre, fed by both slope waters and Gulf Stream. Temperatures are considered to be
close to threshold for both cold and warm-water species.
Distributional patterns displayed by the late winter-early spring collections are
compatible with the proposed model. Also, these collections, taken over a period of
almost three months, reflect marked seasonal changes in faunal composition, par¬
ticularly in Sargasso Sea-Gulf Stream elements.
Twenty-five species and subspecies are described. One species, Globigerina
atlantisae, and one subspecies, Globigerina quinqueloba egelida, are new.
Official publication date is handstamped in a limited number of initial copies and is recorded
in the Institution’s annual report, Smithsonian Year.
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For sale by the Superintendent of Documents, U.S. Government Printing Office
Washington, D.C. 20402 - Price 65 cents (paper cover)
Contents
Pane
Introduction. 1
Acknowledgments. 1
Methodology. 2
Hydrography. 2
Distributional Data. 5
Atlantis 7/-13 Distributional Patterns. 6
Numerical Abundances and Diversity. 6
Stations 2-13, 18, 19, 21 9
Stations 16, 26, 28, 29 9
Stations 32-42 . 10
Summary of Atlantis 77-13 Distributional Patterns
and North Atlantic Circulation. 11
Western Stations. 11
Eastern Stations. 11
Dynamics of Plankton Populations. 12
A Distributional Model for the North Atlantic Current. 12
Atlantis 77-9 Distributional Patterns . 13
Numerical Abundances and Diversity. 13
Stations 286, 288 . 13
Stations 327, 337, 345, 347 13
Stations 385-408 . 13
Measurement of Chambers and Test Volution. 15
Systematic Descriptions. 17
Literature Cited. 43
Plates 1-6. 45
Index . 51
Richard Cifelli Distribution of
and Roberta k. Smith p lanktonic Foraminifera
in the Vicinity of the
North Atlantic Current
Introduction
The North Atlantic Current is that part of the
North Atlantic gyre formed south and east of the
Grand Banks. Although the North Atlantic Current
represents, in part at least, a northern continuation
of the Gulf Stream, it manifests a distinct hydro-
graphic setting. In this paper, planktonic Foraminifera
from the vicinity of this current system are described
and their distributions recorded. In addition, we have
attempted to discern distributional patterns and ex¬
plain them.
This study is based on plankton collections obtained
from two cruises of the Woods Hole Oceanographic
vessel R/V Atlantis II in 1964. The first cruise, At¬
lantis II-9, occupied plankton stations during winter-
early spring between 1 February and 29 April in the
region generally south and east of the Grand Banks.
The second cruise, Atlantis 77-13, occupied stations in
the same general region in fall, between 2 and 21 Sep¬
tember. In addition, stations were occupied during
Atlantis 77—13 west of the Grand Banks, along the
Gulf Stream’s mean path. Figures 1 and 2 show sta¬
tion locations from both cruises with respect to the
major circulatory features of the North Atlantic.
As our studies of North Atlantic planktonic Forami¬
nifera progress, we become increasingly impressed
with the complex dynamics of the distribution of
planktonic organisms. Owing to the environment’s
Richard Cifelli, Department of Paleobiology, National
Museum of Natural History, Smithsonian Institution, Wash¬
ington, D.C. 20560. Roberta K. Smith, Department of
Paleobiology, National Museum of Natural History Smith¬
sonian Institution, Washington, D.C. 20560.
mobility, planktonic organisms are constant, involun¬
tary travelers (if we may be permitted an anthropo¬
morphic metaphor) that, during their lifetimes, may
find themselves in places they do not care to be. There¬
fore, it is difficult to attach spatial limits to species dis¬
tributions or to relate these directly to specific-physio-
chemical factors, such as temperature. Attempts have
been made to do this (e.g., Be, 1968; Boltovskoy,
1968), but these schemes, in our view, both oversim¬
plify the realities of nature and fail to distinguish
among spatial, temporal, and physiochemical aspects
of the environment.
Information is still insufficient to attempt a general
synthesis of planktonic foraminiferal distribution in the
North Atlantic. Therefore, we have, in this study,
limited our interpretations to particular distributional
situations. Because the two cruises offer distinctly dif¬
ferent distributional data, we describe Atlantis 77-9
and Atlantis 77-13 separately. We develop our dis¬
tributional concepts along with the descriptions.
Acknowledgments
The plankton samples described were collected on
cruises 9 and 13 of R/V Atlantis II of the Woods Hole
Oceanographic Institution; it is a pleasure to thank
the scientific parties, officers, and crews during these
cruises for their assistance. Financial support of the
work at sea was variously by the Office of Naval Re¬
search (contract Nonr-2196(00)), the Atomic Energy
Commission (contract AT (30-1)-2174), and the Na¬
tional Science Foundation (grant GP 861) at the
Woods Hole Oceanographic Institution; processing
and distribution of the samples were supported by
1
2
A.E.C. under the contract named. We thank each of
these agencies for its consideration.
V. T. Bowen of the Woods Hole Oceanographic
Institution has read the manuscript, as have F. L.
Parker and W. Berger of the Scripps Institution of
Oceanography; we thank them. Rudolpf S. Sheltema
of the Woods Hole Oceanographic Institution pro¬
vided useful information on circulation patterns of the
North Atlantic and distributional patterns of pelagic
larvae. Brenda Williams assisted in preparation of
samples. Marsha Jessup drew the plates of Foraminif-
era and L. B. Isham prepared the figures. To these
and those other people who have given assistance, we
are most grateful.
This is contribution number 2370 of the Woods
Hole Oceanographic Institution.
Methodology
Samples mainly were obtained in oblique tows from
between 200 and 300 meters with a number 10 plank¬
ton net (0.158 mm aperture) having a ^4-meter open-
mouth diameter. The ship’s towing speed was between
one and two knots. A few samples were obtained from
between zero and 5 meters depth while the ship drifted
on station. Figure 4 shows location, time, and depth of
collections. Samples were preserved in 5 percent for¬
malin, buffered with hexamethylenamine.
After arrival at the laboratory, samples were pre¬
pared and concentrated by the ignition method (Sachs,
Cifelli, and Bowen, 1964; Sachs, 1965; Smith, 1967).
Briefly, (1) formalin is washed out of samples, (2)
samples are digested in sodium hypochlorite or
hydrogen peroxide, (3) the digesting agent is washed
out and the samples dried, (4) samples are ignited
at 500°C in a muffle furnace for approximately 1 to
2 hours, (5) the ashy residue is washed out of ignited
samples, and (6) dried samples are stored in pyrex
petri dishes for subsequent study.
A random specimen count is needed, both to deter¬
mine specimen number per given volume of sea water
and to be sure a taxonomically and numerically rep¬
resentative sample is seen and/or picked. Therefore,
we follow a standard procedure. First, if the prepared
sample is so large that it overcrowds the picking dish—
either making specimens more than one layer thick or
so dense that it is difficult to count specimens in a
given area of the dish—we split the sample to an ap¬
propriate size with a microsplitter.
SMITHSONIAN CONTRIBUTIONS TO PALEOBIOLOGY
We use a rectangular metal picking dish with a grid
of 100 divisions (Smith, 1967). If the sample contains
less than 500 specimens, all are examined, counted,
picked, and identified. If more are present, we select
a random sample by using a table of random numbers
to indicate the particular numbered rectangles in the
picking dish in which specimens are to be counted.
Thus, by obtaining a continuing mean as specimens
from different randomly selected rectangles are
counted, examination of 10 to 20 rectangles usually
suffices to determine the total specimen number in
the sample or per given volume of sea water. We
usually pick and identify between 300 and 400 speci¬
mens (every specimen in the randomly designated rec¬
tangles). Occasionally, it is necessary to pick more.
Care should be exercised to spread the sample as evenly
as possible in the picking dish so as to reduce the num¬
ber of rectangles necessary for consideration to reach a
nearly constant mean.
Subsequent to picking, all specimens are arranged
according to species in an assemblage slide. Numbers
of individuals of each species or taxon are then counted.
From these numbers, absolute and relative abundances
are calculated by comparing with the total number in
the slide and sample.
Hydrography
In Figures 1 and 2 the Atlantis 77-13 and -9 stations
are plotted on Sheltema’s (1968, unpublished data,
W.H.O.I.) North Atlantic circulation scheme. This
compilation appears a reasonable compromise of pre¬
viously proposed circulatory systems (Stommel, 1958;
Worthington, 1962; Mann, 1967). It shows North
Atlantic circulation as essentially a single, clockwise,
asymmetrical gyre, with the Gulf Stream swinging
southeast at about longitude 50° W and the North
Atlantic Current forming a more or less separate eddy
of restricted dimensions.
Stommel (1965) gives a thorough account of the
western North Atlantic hydrography, particularly re¬
garding boundary conditions. The principal circula¬
tory feature is the Gulf Stream, which originates in
the Straits of Florida and flows clockwise and north¬
easterly between the Sargasso Sea east and south, and
the slope waters west and north. It does not move in
a straight course, but flows in meanders which some¬
times develop into detached eddies, and the position
varies appreciably throughout the year. The Gulf
NUMBER 4
3
Figure 1. — Atlantis 77-13 stations plotted with respect to surface circulation (after Scheltema,
unpublished data, Woods Hole Oceanographic Institution).
Stream, therefore, is a dynamic but effective boundary
between the distinctive cold slope waters and warm
Sargasso Sea. It shows a strong temperature gradient
at the surface and in subsurface. Stommel (1958, p.
173) states, “The Gulf Stream is not a river of hot
water flowing through the ocean, but a narrow ribbon
of high-velocity water acting as a boundary that pre¬
vents the warm water on the Sargasso Sea (right-hand)
side from overflowing the colder, denser waters on the
inshore (left-hand) side.” The concept of the Gulf
Stream as a boundary rather than a river of water
has important bearing on interpretation of distribution
of planktonic organisms in the North Atlantic.
The Gulf Stream can be traced about as far as longi¬
tude 50 °W where it passes southeast of the Grand
Banks. From there on the continuation appears to con¬
sist of several distinct currents, but the nature of these
currents still is obscure. Apparently, the Gulf Stream
splits into two main branches (Sverdrup, Johnson, and
Fleming, 1942, fig. 187; Stommel, 1965). The stronger
branch is diverted north as the North Atlantic Current.
The southern branch moves diffusedly clockwise south¬
east and blends with the Canaries Current east of the
Azores. According to this view, the North Atlantic
comprises a single gyre with no sharp eastern boundary
of the Sargasso Sea.
Worthington (1962) proposes a different scheme
for eastern North Atlantic circulation, whereby the
Gulf Stream turns entirely southeast after passing the
Grand Banks, completing a western Atlantic gyre.
Northeast of this gyre is another, separated from the
first by a low pressure trough over the southeastern
SMITHSONIAN CONTRIBUTIONS TO PALEOBIOLOGY
Figure 2 .—Atlantis II-9 stations plotted with respect to surface circulation (after Scheltema,
unpublished data. Woods Hole Oceanographic Institution).
Newfoundland Ridge. This trough is considered per¬
manent, so that two separate gyres maintaining two
more-or-less distinct water regimes compose North
Atlantic circulation.
Mann (1967) proposes a scheme that, in some ways,
is a compromise of the previous ones. Accordingly, the
Gulf Stream does swing south at about latitude 50°W,
as suggested by Worthington. Mann, however, rejects
the North Atlantic Current as part of a separate gyre.
He proposes, instead, that both slope water and a
northern branch of the Gulf Stream, flowing north and
east, feed the North Atlantic Current. It is true, how¬
ever, that Gulf Stream and northern-water sources of
the North Atlantic Current are still poorly known.
Mann also suggests that the Gulf Stream swings
sharply south at about latitude 35°N and longitude
40° W. Unfortunately, Mann’s data do not extend east
of longitude 40°W, and thus do not pertain to the
eastern Atlantis 77-13 and -9 stations. His scheme,
however, does suggest that the North Atlantic Current
forms a partially closed eddy northeast of the main
gyre. As both Gulf Stream and slope waters feed the
eddy, a water regime results with planktonic popula¬
tions displaying unique dynamic relationships, as dis¬
cussed later.
The North Atlantic Current forms a devious path
of the North Atlantic gyre that eventually blends with
the Canaries Current to the east and the Sargasso Sea
to the south, at about latitude 35°N. Therefore, the
essential continuity of North Atlantic circulation as a
single clockwise gyre is maintained, and the North At¬
lantic Current behaves as an extension of the Gulf
NUMBER 4
5
Stream as a transport medium. The continuity of Gulf
Stream-North Atlantic Current circulation is evi¬
denced by drift bottles released from eastern North
America and recovered in the Azores and the trans¬
oceanic occurrences of numerous pelagic larvae of
tropical shallow-water benthonic invertebrates (Shel-
tema, personal communication). Many pelagic larvae
have been recovered along the general course of the
North Atlantic Current. At the same time, however,
the North Atlantic Current is distinct from the Gulf
Stream. A significant feature of the Gulf Stream is that
it borders the Sargasso Sea. No part of the North At¬
lantic Current eddy is comparable to the Sargasso Sea
as the 18° water, a distinctive feature of the Sargasso
Sea (Worthington, 1959) is lacking there (Sverdrup,
Johnson, and Fleming, 1942, fig. 186).
Distributional Data
Before summarizing the Atlantis 77-13 and -9 data
and the distributional patterns implied by them, we
will review some previous North Atlantic distributional
data. While these data are few and mostly limited to
the Western North Atlantic, they serve as a useful
framework for interpreting the Atlantis 77-13 and -9
faunas.
A study of four seasonal traverses across the Gulf
Stream (Cifelli, 1962) strongly suggests that the west¬
ern North Atlantic could be viewed as containing two
distinct endemic faunas. One consists essentially of
Globigerina species and is found in the slope waters
north of the Gulf Stream. The other consists of a di¬
verse group of species belonging to several genera, but
with numerically few representatives of Globigerina.
This fauna occurs in the Sargasso Sea and Gulf Stream.
The Gulf Stream also must contain elements carried
from the Caribbean Sea, but thus far distinctly diag¬
nostic Caribbean elements have not been recognized.
The Gulf Stream fauna conforms with the concept that
the Gulf Stream forms the western border of the Sar¬
gasso Sea (Stommel, 1965).
In slope waters adjacent to the Gulf Stream, Globig¬
erina species are found with Sargasso Sea and Gulf
Stream species. This is the boundary fauna and gener¬
ally, the frequency of Globigerina species increases with
distance north of the Gulf Stream’s mean path. The
boundary between the Gulf Stream and slope waters,
however, cannot be defined rigidly because its extent
and position vary considerably throughout the year.
359-866 0—70-2
Seasonal faunal boundary variations most likely result
from changes in position and extent of the Gulf Stream.
According to the concept of two endemic western
North Atlantic faunas, assemblages in the slope-water
boundary are regarded as faunal mixtures rather than
faunal transitions. Although the two western North
Atlantic faunas appear to maintain their identity
throughout the year, significant seasonal variations in
species frequency-relationships occur (Be, 1960b;
Cifelli, 1962, 1965). Although these variations are not
fully understood, particularly those occurring north
of the Gulf Stream, some known aspects bear on the in¬
terpretation of the Atlantis II traverses.
In the Sargasso Sea-Gulf Stream fauna, a spectacu¬
lar change in species dominance occurs between sum¬
mer and winter. In summer and fall, Globigerinoides
ruber is dominant, but after the fall turnover it strongly
declines, along with other Globigerinoides species. In
winter, G. ruber appears mostly in negligible percent¬
ages, while Globorotalia truncatulinoides is dominant.
During late winter, G. truncatulinoides declines and
G. hirsuta achieves dominance. In spring, Globigeri¬
noides ruber again becomes dominant, but Globigeri-
nella aequilateralis also occurs in high frequencies.
The extent of slope-water fauna seasonal change is
much less clear than in the Sargasso Sea-Gulf Stream
fauna. Partly, the obscurity results from the slope-
water fauna’s greater degree of local lateral variation,
which, in turn, may result from the slope-water envi¬
ronment’s greater variability than the Sargasso Sea.
Yet, past work (Cifelli, 1965, pp. 5-8) reveals some
spatial and temporal frequency changes of Globigerina
species which might help explain some Atlantis 77-13
and -9 frequency relationships.
In previous traverses across western slope waters,
maximum concentrations of Globigerina inflata were
found during fall in inner slope waters, relatively close
to the Gulf Stream (Cifelli, 1965, p. 6). Be and Hamlin
(1967, p. 102) also found G. inflata in high concen¬
trations during summer in inner slope waters and con¬
sidered it an indicator of “transitional waters.” They
also found it considerably less common in the eastern
Atlantic in summer.
Globigerina quinqueloba egelida, new subspecies,
exhibited peak development in western slope waters
during winter (Cifelli, 1965, p. 7) and was relatively
scarce during summer. Be and Hamlin (1967) found
G. quinqueloba egelida maxima during summer in the
subarctic region. G. incompta has exhibited maxima
6
SMITHSONIAN CONTRIBUTIONS TO PALEOBIOLOGY
in western slope waters during summer and fall, with
frequencies being generally higher farther north of the
Gulf Stream than those of G. inflata.
From the above data it is clear that the slope-water
and Sargasso Sea-Gulf Stream faunas each undergo
significant changes in species frequencies during the
year. In comparing faunas, one should take into
account these seasonal changes.
The Atlantis 11-13 and -9 collections were made
when North Atlantic waters were, respectively, warm¬
est and coldest. These collections provide some infor¬
mation on seasonal faunal changes in the vicinity of
the North Atlantic Current which is needed for mean¬
ingful comparison of this part of the North Atlantic
water regime with that farther west. Because of the
marked difference in seasonal setting of the Atlantis
11-13 and -9 cruises, they will be treated separately in
the sections that follow. The check list (Figure 4)
gives data on the occurrence and numerical abundance
of all species from both cruises.
Atlantis 11-13 Distributional Patterns
The Atlantis 11-13 traverse covers much of the
breadth of the North Atlantic, transecting a region of
complex circulation. Changes in faunal associations
are complex and difficult of interpretation because of
the complexities of the planktonic environment and
circulation in the region of the traverse; however, the
tendency toward mutual exclusivity of Globigerinoides
ruber, Globigerina incompta, and G. quinqueloba
egelida, new subspecies, reveals some pattern. Figure 5
shows this, where the frequency of each is shown as
a percent of the total of the three, not the total
foraminiferal populations. Three more-or-less distinct
populations are suggested, with only stations 4 and 29
appearing transitional. Moreover, these station group¬
ings by frequency are spatially compatible (Figure 1).
Therefore, stations are grouped spatially and evalu¬
ated in light of the three distributional patterns sug¬
gested by the frequency relationships. As the stations
were occupied in September, the summer (Cifelli,
1965; Be and Hamlin, 1967) and fall (Cifelli, 1965)
seasonal data are used as references.
Numerical Abundances and Diversity
Numerical abundances vary from about 200 to 80,000
specimens per 1,000 cubic meters of sea water. Most
values compare favorably with those found previously
in western Atlantic slope waters (Cifelli and Sachs,
1966). The western part of the traverse (stations
2, 4, 5, 8), however, shows counts less than 6,000
per 1,000 cubic meters, compared to previous counts
Figure 3. — Numerical abundance relationships among Globigerinoides ruber, Globigerina
incompta, G. quinqueloba egelida, new subspecies, G. inflata, and G. bulloides, sensu lato from
Atlantis 11—13 stations.
4I°04'
29°I2‘
7
Figure 4. —Check list of planktonic Formaminifera, Atlantis 77-13 and Atlantis 77-9 stations.
8
SMITHSONIAN CONTRIBUTIONS TO PALEOBIOLOGY
Globigerina aff G. quinqueloba
Figure 5. —Frequency relationships among Globigerina incompta, G. quinqueloba egelida, new
subspecies, and Globigerinoides ruber from Atlantis 77—13 stations.
of over 15,000. Highest abundances come from the
eastern part of the traverse, with the maximum of
80,000 from station 34.
Diversity is relatively high throughout the traverse,
ranging between 12 and 21 per station and with no
significant correlation between dominant species and
diversity apparent. Stations and their diversities are,
respectively: 2—12; 4—14; 5—18; 8—17; 9—13;
13—14; 16—14; 18—21; 19—17; 21—16; 26—14;
28—15; 29—17; 32—18; 34—15; 36—15; 38—18;
40—14; 42—17.
Many species are ubiquitous, but only six represent
10 or more percent of total populations. These are
Globigerinoides ruber, Globigerina incompta, G.
quinqueloba egelida, new subspecies, G. inflata, G.
bulloides, sensu lato, and Globigerinella aequilateralis.
Figure 3 shows the number of specimens of these
species per 1,000 cubic meters of sea water at each
station. G. aequilateralis is excluded because it is only
fairly well developed at three stations (Figure 4).
These species’ maximum-development areas, percent¬
ages, and numerical abundances may be summarized
as follows.
Globigerinoides ruber is maximally developed in the
western area, parallel to or in the path of the Gulf
Stream, at stations 5, 8, 9, 13, 18, 19, and 21; it
reaches a maximum percent of the fauna of 55 at
station 21 and a maximum abundance per 1,000 cubic
meters of 20,000 at station 9. Globigerina incompta is
maximally developed in the eastern area at stations
32, 34, 36, 38, 40, and 42; it reaches a maximum
percent of 72 at station 36 and a maximum abun¬
dance of 70,000 per 1,000 cubic meters at station 34.
Globigerina quinqueloba egelida, new subspecies, is
NUMBER 4
9
maximally developed at northern stations 16, 26, and
28, reaches 55 percent at stations 16 and 26, and shows
a maximum abundance of 25,000 per 1,000 cubic
meters at station 28. Globigerina inflata is maximally
developed at far western stations 2, 4, and 5, reaches
35 percent at station 4, and shows a maximum abun¬
dance of 5,500 per 1,000 cubic meters at station 5.
Globigerina bulloides, sensu latio, is maximally devel¬
oped at eastern stations 32 and 34, reaches 29 percent
at station 32 and a numerical abundance of 15,000 per
1,000 cubic meters at station 34. Globigerinella aequi-
lateralis is best developed at western stations 5, 8, and
13, reaches 23 percent at station 5 and a numerical
abundance of 2,500 per 1,000 cubic meters at station
13.
Stations 2-13, 18, 19, 21
Stations of the western part of the traverse share a
common distributional pattern. Stations 2-13 are close
to the Gulf Stream’s mean path or its meanders.
Stations 18, 19, and 21, located beyond the
Gulf Stream path, are still within the influence of its
southern branch. Except for station 4, all show high
relative frequencies of the dominant warm-water form,
Globigerinoides ruber, with respect to Globigerina in-
compta and G. quinqueloba egelida, new subspecies
(Figure 3). Frequencies of Globigerinoides ruber and
other species indicate a boundary fauna occurring
adjacent to the Gulf Stream. G. ruber strongly domi¬
nates at stations 18, 19, and 21, and 9 and 13, decreas¬
ing westerly. This decrease is not unexpected, as the
Gulf Stream mean path, swinging from the southwest,
does not reach the latitudes of Atlantis II- 13 stations
until about 55 °W longitude, closest to stations 9
and 13.
Gulf Stream meandering could account for the
variability in species frequency relationships at stations
2-8. Good overall agreement exists in faunal composi¬
tion between these stations and those previously oc¬
cupied during fall in the slope waters close to, but at
varying distances from, the Gulf Stream (Cifelli, 1965,
p. 6). The principal Globigerina species is G. inflata,
previously seen best developed in western slope waters
during fall and closer to the Gulf Stream than other
Globigerina species.
The fairly numerous globigerinas and relatively few
Globigerinoides ruber at stations 2 and 4 (Figure 4)
suggest their farthest removal from the Gulf Stream.
Station 4 being farthest removed from the Gulf Stream
can explain what we previously (Cifelli and Smith,
1969) thought an instance of patchiness. Although
station 4 is no farther from the mean Gulf Stream path
than 2 and 5, meandering may have placed 2 and 5
closer to Gulf Stream water. Patchiness in that region
might be due to mixing of slope and Gulf Stream
waters.
The general identity of the western faunal pattern
continues east and north of the Grand Banks at sta¬
tions 18, 19, and 21. Globigerinoides ruber dominates
and has frequencies from 45 to 55 percent. Globigerina
frequencies are low, but with G. inflata still the princi¬
pal slope-water representative. The high frequencies of
Globigerinoides ruber correlate with high surface tem¬
peratures at those stations (Figures 5 and 6). Thus,
faunal patterns of the western North Atlantic may ex¬
tend east and north of the Grand Banks, at least to
longitude 46°W. Yet, stations 18, 19, and 21 waters
may be isolated eddies or a continuation of part of the
Gulf Stream. Bathythermographs from this area reveal
unusually rapid lateral changes in surface and subsur¬
face temperatures.
Stations 16, 26, 28, 29
Stations 16, 26, and 28 reveal a distinct distributional
pattern, reflecting their low surface temperatures
(13.5°C to 16.1°C). Globigerina quinqueloba egelida,
new subspecies, dominates and has frequencies between
51 and 55 percent, more comparable to past records
of winter rather than fall distribution in the slope
waters (Cifelli, 1965, p. 7). Likewise, the relatively
low frequencies of G. inflata (5-11 percent) resemble
winter more than fall distribution in slope waters.
Moreover, during summer, G. quinqueloba egelida
maxima were found in the subarctic region (Be and
Hamlin, 1967, pp. 90, 96). Distinct populations, then,
appear between stations 16, 26, and 28 and those of
western slope waters. These populations probably were
stocked mostly from cold Labrador waters.
Frequencies of Globigerinoides ruber (8—16 percent)
and occurrences of other Sargasso Sea—Gulf Stream
species suggest some southern mixture. Yet, mixing ap¬
pears relatively minor considering proximity to warm-
water stations. In particular, station 16 is very close to
a boundary found between relatively cold and warm
bodies of water. As revealed by bathythermographs, a
strong thermal gradient marked the front, apparently
isolating the water bodies and allowing only minimal
faunal mixing. (Note that we speak of the time of
10
SMITHSONIAN CONTRIBUTIONS TO PALEOBIOLOGY
Figure 6. —Relationship between percentage of combined species of Globigerina (exclusive of
G. inflata) and surface temperature from Atlantis 77-13 stations.
collection of the Atlantis 11-13 stations, as the local
hydrography varies within limits seasonally and prob¬
ably also over greater time spans. Thus, conditions at
particular geographic points are subject to change.)
The traverse’s northernmost station, 29, appears to
represent an area of effective mixing. The frequency
relationships of Globigerinoides ruber and Globigerina
quinqueloba egelida, and also G. inflata, indicate a
transitional fauna (Figures 3, 4). The 17.1°C surface
temperature is intermediate between cold-water G.
quinqueloba egelida stations and those at previously
discussed warmer-water stations. Further, bathy¬
thermographs reveal no steep thermal gradients nor
marked cold fronts in the vicinity of station 29.
Stations 32^-2
Stations 32-42, from east of longitude 40°W, reveal a
third distributional pattern. Like the previous group of
stations, slope-water elements make up the bulk of the
populations, but Globigerina incompta rather than G.
quinqueloba egelida, new subspecies, dominates. Nu¬
merous Sargasso Sea-Gulf Stream species occur, but
their frequencies are consistently low. Of the latter,
Globigerinoides ruber is the chief representative, as at
the previous stations. Globigerina bulloides, sensu lato
is more abundant than elsewhere. G. inflata appears in
relatively low percentages. Overall, stations 32-42 com¬
pare best with outer slope stations during fall (Cifelli,
1965, p. 6). The great spatial separation, however, with
the distinct faunal pattern of stations 16, 18, and 19,
and 29 in between, rules out a direct relationship be¬
tween the water bodies represented by these groups of
stations. The stations 32-42 faunal pattern strongly
suggests a water regime distinct from those to the west.
Figure 6 shows the frequency relationship between
combined Globigerina species and surface temperature.
It further indicates the distributional pattern’s unique¬
ness in the eastern waters. ( G. inflata is here excluded
because of its uncertain generic placement (Cifelli,
1965, p. 14).) The Globigerina frequency-surface tem¬
perature correlation allows projection of a line through
stations 2-29 showing a remarkably good general in-
NUMBER 4
11
verse relationship (Figure 6). Stations 32-42, however,
cluster above the line; Globigerina frequencies are
significantly higher than expected from the relatively
high surface temperatures, using the western stations
(2-29) as a reference. Interestingly, though, stations
32-42 tend to cluster such that a line showing an
inverse relationship in the North Atlantic Current can
be drawn through them also. The relationship differs,
however, not only in showing higher temperatures but
also in showing more variation among the eastern
stations. Further, deviation from western-stations rela¬
tionships appears to increase with distance from west¬
ern stations.
Further to the south, stations 2 and 3 of Chain
cruise 21, about 12° due south of Atlantis 77-13 sta¬
tion 42 (Figure 1) had yielded typical Sargasso Sea
assemblages (Cifelli, 1967, p. 122). These contrast
sharply with those from stations 32-42. Although these
Chain stations were occupied in December, assemblages
contained one or less percent Globigerina, with Globi-
gerinella aequilateralis and Globigerinoides ruber
dominant.
The anomaly shown by stations 32-42 has im¬
portant implications. Slope-water species of Globige¬
rina, particularly G. incompta, thrive in the North
Atlantic Current at surface temperatures favoring
flourishment of Globigerinoides ruber or other Sar¬
gasso Sea—Gulf Stream forms in the western North
Atlantic. This implies the existence of a peculiar dy¬
namic structure in the North Atlantic Current that
strongly influences the composition of plankton popu¬
lations. Therefore, in the fossil record, an increase in
“cold-water” forms (such as slope-water species of
Globigerina) need not necessarily imply a decrease in
temperature of surface waters. A hypothetical explana¬
tion of the Globigerina anomaly will be given in the
following section.
Summary of Atlantis 77-13 Distributional Patterns
and North Atlantic Circulation
Western Stations
West of 50° W, where circulation is best known, dis¬
tributional patterns relate closely to the broad aspects
of the circulation. Planktonic foraminiferal assemblages
from stations 2-13 show frequency relationships char¬
acteristic of inner slope waters relatively close to the
Gulf Stream during fall. Allowances for distances from
the mean position of the Gulf Stream and its meander-
ings can account for variations in species frequency
relationships among these stations. Stations 18, 19,
and 21, near the North Atlantic Current, show similar
faunal patterns. These stations are southeast of the
Grand Banks, near where the North Atlantic Current
is formed, suggesting a dynamic continuity with the
waters farther west. Slope-water assemblages char¬
acterize stations 16, 26, and 28 and the dominance of
Globigerina quinqueloba egelida, new subspecies, in¬
dicates the influence of cold Labrador water. Roughly
equal frequencies of slope-water and Sargasso Sea—
Gulf Stream elements at station 29 indicate water mix¬
ture there.
Eastern Stations
East of 50 °W a marked change in distributional pat¬
tern occurs and we believe this change is associated
with the dynamics of the circulation. Stations 32-42
are at the edge of and within the eddy formed by the
North Atlantic Current (Figure 1). While the Gulf
Stream partly feeds the North Atlantic Current, the
water regime is distinct because the North Atlantic
Current is not a border of the Sargasso Sea as is the
Gulf Stream. Bathythermographs reveal that the waters
around stations 32-42 lack the homogenous layer of
18°C water that characterizes the Sargasso Sea
(Worthington, 1959). The North Atlantic Current is
fed by both slope water and the Gulf Stream. No dra¬
matic boundary exists between two major hydro-
graphic provinces with different endemic faunas as
is seen crossing the Gulf Stream. Under these circum¬
stances, one might expect a distinct communal struc¬
ture in the waters associated with the North Atlantic
Current. The high frequencies of Globigerina species
at stations 32-42, therefore, probably indicate the in¬
dividuality of North Atlantic Current communal struc¬
tures, where the water regime cannot be directly com¬
pared with those to the west.
The North Atlantic Current, however, is not a
closed system. It forms a devious path of the North
Atlantic gyre that eventually blends with the Canaries
Current to the east and the Sargasso Sea to the south,
at about latitude 35°N. Therefore, the continuity of a
single clockwise gyre is maintained, and the North At¬
lantic Current is a Gulf Stream extension as a trans¬
port medium. The circulation continuity is evidenced
by drift bottles released from eastern North America
and recovered in the Azores and the transoceanic oc-
12
SMITHSONIAN CONTRIBUTIONS TO PALEOBIOLOGY
currences of numerous pelagic larvae of tropical shal¬
low-water benthonic invertebrates (Scheltema,
personal communication). Many pelagic larvae have
been recovered along the general course of the North
Atlantic Current.
Before attempting to explain the peculiar communal
structures of the North Atlantic Current, we believe it
necessary to consider some aspects of plankton popula¬
tion dynamics. Actually, little is known about this sub¬
ject and we approach it in broad, hypothetical terms.
Dynamics of Plankton Populations
Because the open ocean continually is in motion, its
dwellers are constant travelers who, during their life¬
times, may occupy a considerable range of habitat. In
general, one can recognize three categories of open-
ocean dwellers, each bearing distinctive dynamic rela¬
tionships to the environment. One group comprises the
free swimmers, as fishes, which live entirely in the open
sea. Being locomotive, they are somewhat independent
of the water motion and can, within limits, choose en¬
vironments most favorable to productivity and flourish -
ment. The other two groups are free floaters, negli¬
gibly locomotive, and thus involuntarily transported by
ocean currents. The free floaters include (1) pelagic
larvae of benthonic organisms and (2) truly planktonic
organisms, such as the Foraminifera. Dynamically, the
major distinction is that the former do not achieve ma¬
turity during their travels while the latter live and re¬
produce entirely in the open sea. However, the itiner¬
aries and destinies of all free floaters are determined
by water movements.
The first free-floater group constitutes excellent in¬
dicators of water movement since no productivity
occurs during travel, leaving population structure un¬
changed except for downstream numerical and diversi¬
ty decreases from mortalities. One can also determine
points at which larvae are “seeded” into the environ¬
ment. Scheltema (personal communication) views
North Atlantic circulation as a giant carrousel along
which the larvae are riders that may jump off at any
time. Truly planktonic organisms also ride this car¬
rousel but where they get on or jump off is not
obvious.
A Distributional Model
for the North Atlantic Current
North Atlantic Current stations 32-42 are character¬
ized by high standing crops. Numerical values are par¬
ticularly high compared to adjacent stations 18, 19,
and 21, located southwestward, where the Gulf Stream
begins its swing northeast as part of the North Atlantic
Current. We believe the high standing corps at stations
32-42 reflect increased productivity, resulting from
convergence of slope waters and Gulf Stream (form¬
ing the North Atlantic Current) ; however, slope-water
species dominate; Sargasso Sea-Gulf Stream species
show fairly high diversity, but occur in consistently low
frequencies.
Globigerina incompta shows the highest numerical
abundance, which accounts for its strong dominance.
Also, with stations 32-42, an inverse relationship may
exist between standing crop of total population and
frequency of G. incompta. Stations 34, 36, and 38 have
the highest standing crops and lower frequencies of G.
incompta than 32, 40, and 42 (Figure 3). Perhaps sig¬
nificantly, stations 40 and 42 are farthest south in the
North Atlantic Current. This suggests a gradient, along
which G. incompta achieves a maximum through pro¬
ductivity and then declines to the south. Further, south
of station 42, at Chain 21 stations 2 and 3 (Figure 1;
see Cifelli, 1967, Text-fig. 1) Globigerina species are
scarce or absent.
Figure 7 illustrates the hypothetical model for our
explanation. The North Atlantic Current forms a par¬
tially closed eddy with a dynamic setting different from
that to the west. No conspicuous boundaries exist and
conditions are potentially favorable to productivity.
Importantly, we assume that the North Atlantic Cur¬
rent temperatures remain close to threshold. They are
both close to tolerance maxima of Globigerina slope-
water species and to minima, at least for reproduction,
Figure 7.—Schematic model of faunal relationships in the
general area of the North Atlantic Current.
NUMBER 4
13
of Sargasso Sea species. As populations sweep along the
North Atlantic Current, they arrive at the productively
favorable area within temperature tolerances of Glo¬
bigerina incompta and other Globigerina species. The
particular circumstances favoring preferential produc¬
tivity of G. incompta are unknown, but unique, in
terms of our past experience, is a species flourishing
where temperatures must be close to its tolerance
maximum. Yet, perhaps this should not be too sur¬
prising, as poikilitic animals often show optimum de¬
velopment at temperatures closer to the maximum
than the minium of their range. At the same time,
temperatures may be below reproductive minima of
Globigerinoides ruber and other Sargasso Sea forms.
As populations continue clockwise movement south,
conditions favorable to Globigerina incompta produc¬
tivity diminish and it decreases both in numerical
abundance and relative frequency. Eventually, the
populations pass a temperature threshold, where G.
incompta and other Globigerina species severely de¬
cline, finally being completely removed. Then popu¬
lation compositions are that of the Sargasso Sea. Chain
21 stations 2 and 3 from the southern North Atlantic
Current (Cifelli, 1967) have typical Sargasso Sea type
populations.
The explanation for foraminiferal distribution that
we propose is hypothetical, but we believe it can be
tested by detailed sampling and hydrographic survey¬
ing across the North Atlantic Current.
Atlantis II -9 Distributional Patterns
The Atlantis II-9 stations, distributed over a wide re¬
gion east of longitude 50°W, were occupied between 2
February and 29 April 1964. Since surface-water
warming begins about the end of March, temperatures
were close to minimum, whereas Atlantis 77-13 tem¬
peratures were close to maximum. Stations were located
in or close to the North Atlantic Current eddy, with
some exceptions (Figure 2). Stations 286 and 288
were distantly removed from the others; station 327
was near the southern branch of the Gulf Stream; and
station 408 was close to the North Atlantic Current’s
western boundary.
Since the Atlantis 77-9 stations were collected over a
period of almost three months, one cannot view distri¬
butional patterns quasisynoptically, as with the Atlantis
77-13 stations. The Atlantis 77-9 traverse actually rep¬
resents three transects;*with time lapses of about (1)
one and (2) one and a half months. These time lapses
introduce seasonal change in interpreting distribution;
seasonal change seems evidenced in the Sargasso Sea
components. For this reason, we treat the Atlantis 11-9
stations as three transects, according to collection time.
Numerical Abundances and Diversity
Standing crops at Atlantis 77-9 stations are relatively
low, from less than 100 to about 14,000 specimens per
1,000 cubic meters of sea water at those stations having
current-meter readings. Diversities also are low, with
only 4 to 12 species per station. Species frequencies dif¬
fer considerably from the Atlantis 77-13 traverse. Glo¬
bigerina inflata, G. bulloides, sensu lato, Globorotalia
hirsuta and, to a lesser degree, G. truncatulinoides
more or less replace the Atlantis 77-13 dominants
Globigerina incompta, G. quinqueloba egelida, new
subspecies, and Globigerinoides ruber.
The Atlantis 77-9 stations display a generally inverse
correlation between frequency of combined Globi¬
gerina species (exclusive of G. inflata) and surface
temperature, similar to Atlantis 77-13 stations. Figure
6 compares these correlations. Stations 286 and 288
appear anomalous.
The inverse Globigerina- temperature correlations of
the two Atlantis II traverses nearly parallel, with no
station-group overlaps. The relative Globigerina spe¬
cies-increase with lower temperatures is less with
Atlantis 11-9 than Atlantis 77-13 stations. This paral¬
lel relationship is not entirely clear, but supports sur¬
face temperature not directly affecting development
of slope-water species of Globigerina. As stated before,
we think the Globigerina species frequency-surface
temperature relationship largely reflects interaction of
water regimes and population dynamics.
Stations 286, 288
These two stations were the first collected (1 and 2
February) and are considerably northeast of the others.
Fifty percent of the station 286 assemblage is the non-
planktonic species Planorbulina mediterranensis and
Tretomphalus atlanticus, the latter lacking float cham¬
bers, indicating a benthonic habitat. We cannot ex¬
plain the open-ocean concentration of benthonic forms.
Perhaps they attached to sea-grass, or, possibly, station
286 is over a shallow, uncharted seamount. Nearby
station 288, nor any other station, reveal no benthonic
forms.
14
Planktonic populations of stations 286 and 288 are
very similar. Both show unusually low standing crops
(66 and 239 specimens per 1,000 cubic meters, re¬
spectively) . Globigerina inflata strongly dominates,
with about 75 percent (discounting station 286 ben-
thonics). Virtually the only Sargasso Sea species is
Globorotalia truncatulinoid.es, achieving 11 percent at
station 288. It indicates Gulf Stream influence in these
northeastern waters. It strongly dominates in the
northern Sargasso Sea during January (Be, 1960b;
Cifelli, 1962) ; thus it is the most likely Gulf Stream
contribution at stations 286 and 288 collecting time.
Probably G. truncatulinoides does not produce in these
cold, northeastern waters; low standing crops at sta¬
tions 286 and 288 indicate a general productivity lack
and largely dormant populations.
Strong dominance of Globigerina inflata largely ac¬
counts for the anomalously low frequencies of other
slope-water Globigerina species at these stations with
the traverse’s minimum surface temperatures (10.0°
and 10.2°C). Yet, the anomaly remains striking. Fre¬
quencies of G. inflata at stations 286 and 288 are the
highest observed for this species. Moreover, in the
western North Atlantic, G. inflata normally is a
“warmer-water” Globigerina, favoring inner slope
waters near the Gulf Stream and with maximum devel¬
opment in fall (Cifelli, 1965; Be and Hamlin, 1967).
Dominance of G. inflata in waters distant from western
Atlantic slope waters well illustrates that species fre¬
quency relationships may vary with water regime as
well as season.
Stations 327, 337, 345, 347
These stations, collected between 16 and 22 March,
extend northeast from near the southern Gulf Stream
branch on into the North Atlantic Current eddy (Fig¬
ure 2). Station 327, nearest the Gulf Stream branch,
reveals a boundary assemblage with nearly equal slope-
water Globigerina and Sargasso Sea forms. The princi¬
pal species, at 29 percent, is the Sargasso Sea form
Globorotalia hirsuta. Winter changes in the northern
Sargasso Sea are reflected in G. hirsuta replacing G.
truncatulinoides as dominant. Chain cruise 25 reveals
G. hirsuta as similarly dominant in the northern Sar¬
gasso Sea during early April (Cifelli and Smith, 1969).
Station 337 begins to show a frequency decline of G.
hirsuta and a large relative increase of Globigerina.
Those (345, 347) to the north, in the North Atlantic
Current have this relationship well developed. The
SMITHSONIAN CONTRIBUTIONS TO PALEOBIOLOGY
principal Globigerina species is G. bulloides, sensu lato,
with 64 percent at station 345. Frequency relationship
changes among stations 327, 337, 345, and 347 are the
kind expected from the positions relative to the south¬
ern branch of the Gulf Stream (Figures 2, 4).
Stations 385-408
These stations, collected between 26 and 29 April, ex¬
tend northwest and west across the North Atlantic
Current eddy (Figure 2). The North Atlantic Current
western boundary probably falls between stations 404
and 408. The surface temperature change suggests this,
decreasing from 13.9°C at station 404 to 10.4°C at
station 408. Further, a significant faunal change oc¬
curs between station 408 and the adjacent easterly
stations.
The Atlantis 11-9 station 408 assemblage (45° 10' N,
45° 39' W) indicates Labrador Current waters. This
assemblage closely resembles one collected in the west¬
ern Labrador Current in early April during Chain
cruise 25, station 462 (42°00' N, 65°00' W). The two
assemblages are compared in Table 1.
Table 1 . —Species frequency relationships between Chain
25, station 462 and Atlantis 11-9, station 408
Species
Station 462
3 April
1962
(percent)
Station 408
29 April
1964
(percent)
Globigerina bulloides, sensu lato
66
62
G. incompta
18
6
G. inflata
2
5
G. quinqueloba egelida
10
15
Globigerinita glutinata
2
11
Globorotalia hirsuta
0
>1
Orbulina universa
2
0
Probably most significant is the frequency relation¬
ship between Globigerina bulloides, sensu lato, and G.
inflata. At both stations, G. bulloides, sensu lato,
strongly dominates, with low percentages of G. inflata.
At Atlantis 11-9 station 404 the relationship is reversed;
G. inflata strongly dominates (69 percent), with few G.
bulloides (3 percent). Nearby station 400 shows nearly
identical frequency relationships, although with some
increase of G. bulloides, sensu lato.
NUMBER 4
15
Frequency relationships within the North Atlantic
Current are not homogeneous, however. Station 397
shows almost equal percentages of G. bulloides, sensu
lato, and G. inflata, and no species exhibits strong
dominance. Station 385, at the southern end of the
North Atlantic Current, reveals only 9 percent G. bul¬
loides, sensu lato, and shows dominance of Globiger-
inita glutinata (36 percent). This variation’s signifi¬
cance is not clear.
Curiously, stations 385-408 are impoverished in
Sargasso Sea forms. Globigerinita glutinata, a ubiqui¬
tous form, is the only species not of Globigerina that oc¬
curs in frequencies of over 10 percent. The Sargasso
Sea form Globorotalia hirsuta composes 6 percent of
the station 404 assemblage. At all other stations, com¬
bined Sargasso Sea forms account for 3 or less percent.
Since we have no quasisynoptic data from the
Sargasso Sea, we can only speculate on the cause of
this impoverishment. Conceivably, however, April is a
critical time in North Altantic planktonic population
dynamics. Previous April data indicate that Globorota¬
lia hirsuta frequency declines rather sharply and forms
such as Globigerinoides ruber and Globigerinella
aequilateralis achieve dominance; however, April
temperatures in the North Atlantic Current are still
relatively low. Perhaps Globigerinoides ruber and
Globigerinella aequilateralis lack as low a temperature
tolerance as Globorotalia hirsuta; the former species
develop maximally in the northern Sargasso Sea be¬
tween spring and fall and are virtually absent there in
winter. Accordingly, in the context of the dynamic
model proposed for Atlantis 11-13 distribution (page
28), we suggest that temperatures are generally below
threshold in the North Atlantic Current for Sargasso
Sea forms and they mainly are unable to survive the
journey around the eddy.
Measurement of Chambers and Test Volution
Among planktonic foraminiferal taxa, particularly
of Globigerina species, differences often are subtle and
occasional morphologic overlap occurs. Because of this,
we add to some species descriptions data on test size
and number of chambers relative to test volution. (The
species are Globigerina atlantisae, new species, G. bul¬
loides bulloides, G. dutertrei, G. incompta, G. aff. G.
pachyderma, and G. quinqueloba egelida, new sub¬
species.) Such data point up resemblances and differ¬
ences among species and assist in establishing popula¬
tion maturity and geographic variation. We hope these
data will allow comparisons in future studies.
In descriptions of coiled Foraminifera, one custo¬
marily includes maximum diameter, total number of
chambers (if determinable) and number of chambers
occupying the periphery. Only rarely is the relationship
between (1) size and/or number of chambers and (2)
coil or degrees of volution examined throughout the
test. Probably for this reason, the chambers occupying
the periphery are defined as the “final whorl” and those
surrounding the proloculus as the “initial whorl.”
One obtains this “final whorl” by rotating the test
‘backward’ 360°, with the final chamber as starting
point (Figure 8). These chambers occupy the periph¬
ery of the test. (Usually, however, the 360° line falls
across the whorl’s innermost chamber, giving a whorl
90'
Figure 8.—Peripheral whorl counting. The cross hairs of
the goniometer microscope eyepiece are represented by the
0°-180° and 90°-270° lines. They are centered in the
proloculus, with the 0°-180° line extending through the
center of the proloculus and the outermost basal edge of the
final chamber. Measurement starts at the intersection of the
line with that basal edge and gives degrees of whorl occupied
by each chamber, with a total of 820°. Chambers are num¬
bered progressively inward, with the final chamber as 1. Each
whorl occupies 360°. Therefore, in this case the peripheral
whorl is occupied by chambers 1, 2, 3, and most of 4; the
pre-peripheral whorl by part of 4, 5, 6, and most of 7; and
720° to 820° by part of 7 and 8. By this method, the
peripheral whorl is complete and it is the chambers immedi¬
ately “younger” than the proloculus which do not complete
a whorl.
16
containing a number of complete chambers plus a
fraction of a chamber.) One obtains the “initial whorl”
by rotating the test ‘forward’ from the proloculus
(Figure 9). Continuation of this ‘forward’ measure¬
ment usually results in the last complete whorl (360°)
extending onto the periphery and thus overlapping the
“final whorl.” (‘Backward’ measurement usually gives
an “initial whorl” short of 360°.)
Although opposite to the direction of growth (see
Cifelli, 1961), practical reasons exist for inward meas¬
urement of chambers with respect to volution. Periph¬
eral chambers are most clearly visible, becoming
progressively less so inward and often barely or not
visible in the prolocular whorl. The number and size
of chambers occupying the periphery are useful, easily
90°
Figure 9. —Initial whorl counting. The cross hairs of the
goniometer microscope eyepiece are represented by the 0°—
180° and 90°-270° lines. They are centered in the proloculus,
with the 0°-180° line extending through the center of the
proloculus and its intersection with the beginning of the first
chamber beyond it. Measurement starts at that intersection
and gives degrees of whorl occupied by each chamber, with
a total of 820°. Chambers are numbered progressively out¬
ward from the proloculus. Each whorl occupies 360°. There¬
fore, in this case, the first whorl is occupied by chambers
1, 2, and most of 3; the second by part of 3, 4, 5, 6, and part
of 7; and the third by part of 7 and 8. By this method, the
third whorl finishes before completing 360° and the chambers
around the periphery are not all included in the third whorl.
SMITHSONIAN CONTRIBUTIONS TO PALEOBIOLOGY
obtained diagnostic criteria. By rotating specimens
reverse to growth, one can determine the relationship
between chamber number and degrees of whorl
throughout much of the test ontogeny, with a fixed
point of reference, even though early chambers may
be obscure. Therefore, we use this method here. To
maintain consistency and avoid ambiguity, however,
we propose the term “peripheral whorl” for the sum
of chambers that occupy the periphery and comprise
a 360° volution when the last-formed chamber is used
as starting point. Peripheral whorl is intended to re¬
place “final whorl” of common usage.
Our procedure for counting and measuring cham¬
bers per whorl follows. The specimen is oriented spiral
side upward on a mechanical stage of a binocular
microscope having a goniometer eyepiece. The goni¬
ometer crosshairs next are rotated until the north-
south line intersects the suture between the ultimate
and penultimate chambers, and the degrees of rotation
are recorded. This process continues so far as cham¬
bers are visible enough to measure. The size (maxi¬
mum diameter) of each volution (360° of rotation)
also is measured and recorded.
The choice of intersection point of the north-south
line with the final chamber’s forward edge and with
the previous chamber’s sutures offers minor problems.
With the final chamber, the point can be at the cham¬
ber base, where it last touches or lies directly above the
earlier-formed whorl, or it can be at the chamber’s
forwardmost projection. With sutures between pre¬
vious chambers, the point can be either at their bases
or outermost visible extremities. Once these choices
have been made, they should be adhered to consistently.
We have compiled graphs showing the relationship
between chamber addition and degrees of volution
for specimens of the species mentioned above. The
graphs are arranged “backwards,” so to speak, as final
chambers are the 0° points, and the curves run op¬
posite to growth direction. This procedure is necessary
to keep the curves open-ended for those specimens
whose early chambers are not clearly visible. Further,
this method avoids the problem of beginning (and
comparing) plots of specimens with their most uncer¬
tain measurements, of chambers immediately surround¬
ing proloculi; even when these chambers can be seen,
their measurements may be rather inexact because of
their very small sizes.
NUMBER 4
17
Systematic Descriptions
Family GLOBIGERINIDAE Carpenter, Parker,
and Jones, 1862
Genus Globigerina d’Orbigny, 1826
Globigerina atlantisae, new species
Plate 1: figures 1, 2, 3
Globigerina radians Egger.—Parker, 1958, p. 278, pi. 5:
fig. 10.
Test compressed, trochospiral, with a rounded, lobate
periphery and a rather elliptical outline; chambers
rapidly enlarging as added, usually between two and
three whorls in the adult with between four and five
chambers in the peripheral whorl and from four to five
in the pre-peripheral whorl; number of chambers rang¬
ing from 8 to 14 in the entire test, usually 10 or 11;
chamber shape appearing elongated along the axis of
coiling on the spiral side, and perpendicularly to the
periphery on the umbilical side, vertically compressed,
especially in the peripheral whorl; sutures distinct, de¬
pressed, narrow, slightly curved to radial on the spiral
side, more curved on the umbilical side, with the spiral
suture following around the bases of the chambers
of the peripheral whorl and meeting the radial sutures
sometimes in a substellate pattern, otherwise lobate;
spiral side of test either almost flat or with early whorls
raised as a plane above the peripheral whorl (Plate 1:
figure 2) ; aperture interiomarginal, umbilical-extra-
um'bilical, a slit reaching close to the periphery, almost
covered by the extended final chamber and small flap
attached to the base of that chamber; wall finely per¬
forate, finely hispid, thin; coiling direction both left
and right, with left slightly predominant; maximum
diameters of primary types 0.23-0.26 mm.
Parker (1958) synonymized her form with Globi¬
gerina radians Egger on the basis of figures for this
species given by Rhumbler (1909). The original figure
is enigmatic, through it resembles Globigerinella
aequilateralis superficially. Rhumbler (1909, p. 11)
stated that the form figured by him as G. radians was
obtained from Egger. Inspection of these figures re¬
veals, however, that the chambers are not so elongate
in the direction of coiling on the spiral side as are those
of the present form or Parker’s specimens, but instead
are distinctly more lobulate. In this regard, they more
closely resemble those of some Globigerinita iota Parker.
The nature of the figures, although revealing a form
similar to both G. iota and Globigerina atlantisae, new
species, does not permit truly detailed comparison.
Globigerina atlantisae, new species, most closely re¬
sembles G. quinqueloba egelida, new subspecies. It dif¬
fers from the latter in its slightly greater curvature of
the sutures. This difference is particularly apparent on
the umbilical side. The chambers of G. atlantisae are
more elongate along the axis of coiling on the spiral
side of the test and less spherical (or subspherical) than
those of G. quinqueloba egelida. Globigerina atlantisae
also has fewer chambers (generally 10 to 11 in the
adult test compared to 13 or 14 in G. quinqueloba
egelida). In the peripheral whorl there are between
four and five chambers instead of the four and a half
to five found in G. quinqueloba egelida. Related to this
is that there is a consistent difference in the peripheral
outline between the two, with an indentation below
and adjacent to the final chamber of G. atlantisae
which is not present with G. quinqueloba egelida (Fig¬
ure 10). The aperture of G. atlantisae usually is ob¬
scured by the final chamber’s flap-like extension, while
G. quinqueloba egelida shows this feature less com¬
monly. Further, the aperture of G. atlantisae extends
closer to the periphery. Both species are compressed,
but G. atlantisae is generally more so, and also generally
has a flatter spiral surface. With G. atlantisae speci¬
mens, chambers tend to occupy more nearly the same
number of degrees of whorl (compared with other
Globigerina atlantisae Globigerina quinqueloba
egelida
Figure 10.—Comparison of outlines of Globigerina altantisae,
new species, and Globigerina quinqueloba egelida, new sub¬
species. Chambers of G. atlantisae are more elongate in the
direction of coiling on the spiral side. Further, the plan of
growth produces a consistant indentation in the outline of
specimens, adjacent to the last chamber, whereas G. quin¬
queloba egelida shows no such indentation; that is, a line
drawn tangent to chambers 1 and 4 will not touch chamber
5 in G. atlantisae, whereas it will intersect chamber 5 in G.
quinqueloba egelida.
18
SMITHSONIAN CONTRIBUTIONS TO PALEOBIOLOGY
-
2^,.
-
2 r - .
-
5 «•» . *
11
PERIPHERAL whorl
15
• 0
-
15 4 * '
-
-
16 .. *
16
r'*’
Globigerina atlantisae
16 . .
0
C
( 16 SPECIMENS)
i 1
16
n
_____1_1_1_1_1_i i_1_1_1_L.
_i_i_i_i_i_i_i i j i_i_i—i—i—
J_1_1_1_1_1_1_1_1_I_1_1_1-■-■- 111!-1
100 200 300 400 500 600 700 800 900 1000 1100
NUMBER OF DEGREES OF WHORL
Figure 11 .—Globigerina atlantisae, new species. A growth pattern expressed as the relationship
between number of chambers and number of degrees of whorl for 16 specimens. The measure¬
ment increase on both axes goes from the final chamber inward, not from proloculus outward.
chambers of the same and other specimens) than is the
case with G. quinqueloba egelida (Figure 11).
Measurements.— Sixteen specimens were selected
to determine the relationship between chamber num¬
ber and degrees of test volution in Globigerina atlan-
Table 2. —Sizes and chamber numbers of 16 specimens of
Globigerina atlantisae, new species
Range
Mean
Maximum diameter (mm)
through peripheral whorl
0. 16-0. 28
0. 22
Maximum diameter (mm)
less peripheral whorl
0. 05-0. 13
0. 09
Ratio of diameters of peripheral
whorl and rest of test
3. 2-2. 2
2.4
Total number of chambers
8-14
11(11. 31)
Number of chambers in periph¬
eral whorl
4. 2-4. 8
4.44
Number of chambers in preper¬
ipheral whorl (for those 12
specimens continuing beyond
this whorl)
4. 4-5. 4
4. 98
tisae, new species (Figure 11). The maximum number
of chambers recorded is 14, but most specimens contain
12 or fewer chambers. In all but four specimens the
chambers occupy more than two but less than three full
whorls. The four specimens consisting of less than two
full whorls probably represent immature forms. Good
consistency exists among specimens in growth pattern
and they plot close to a straight line with a relatively
small spread of points. The peripheral whorl contains
between four and five chambers, which represents a
slight decrease in rate of chamber addition from the
previous 360° of volution (pre-peripheral whorl).
Distribution. —Globigerina atlantisae, new species,
is not common in Atlantis II material. It occurs at
seven Atlantis 11-13 stations and one Atlantis 11-9.
It reaches a peak of 2 percent at station 21.
Globigerina bulloides bulloides d’Orbigny
Plate 1: figures 5, 6
Globigerina bulloides d’Orbigny, 1826, p. 277, nos. 17, 76.—
Brady, 1884, p. 593, pi. 79: fig. 7.—Phleger, Parker, and
NUMBER 4
19
m 6
O'
LU
CD
2
<
X 4
O
It.
O
<r
iu 2
as
PERIPHERAL WHORL
10,.
10
1
10
10 .
10,
10
Globigerina bulloides bulloides
(10 SPECIMENS)
_l_I_I_I_L_
o
<0
ro
1 l i 'll l
O
CVJ
_i_i_L_
100 200 300 400 500 600 700 800
NUMBER OF DEGREES OF WHORL
900
1000
j_ i ■ ■ ■ - i
1100
Figure 12 .—Globigerina bulloides bulloides. A growth pattern expressed as the relationship
between number of chambers and number of degrees of whorl for 10 specimens. The measure¬
ment increase on both axes goes from the final chamber inward, not from proloculus outward.
Pierson, 1953, p. 11, pi. 1: figs. 3, 4, 7, 8.—Parker, 1958,
p. 276, pi. 5; figs. 1-4.—1962, p. 221, pi. 1, figs. 1-8.—Be,
1959, pi. 1, figs. 15-17.—Bradshaw, 1959, p. 33, pi. 6, figs.
1-4;—Banner and Blow, 1960a, p. 3, pi. 1, figs. 1, 4.—
Cifelli, 1965, p. 11, pi. 1, figs. 1-3, 5.
Populations of Globigerina bulloides bulloides in the
Atlantis II material mainly are easily distinguishable
from other groups. Occasional difficulty is encountered
in separation from some forms of Globigerinella aequi-
lateralis in which the growth plan remains essentially
trochospiral. Distinction is made primarily on the
apertural position, which in G. aequilateralis is extra-
umbilical and tends to extend into the equatorial
region. The growth plan of quite immature forms
of Globigerinoides conglobatus is almost identical with
that of Globigerina bulloides bulloides, but the former
species is usually easily distinguishable by its coarsely
hispid wall and the occurrence of suppementary
apertures. A serious problem of differentiation exists
between G. bulloides bulloides and G. bulloides fal-
conensis; this is discussed under the latter taxon. One
of the few specimens of G. bulloides bulloides with a
supplementary aperture is figured (Plate 1; figure 5)
because it is unique.
Measurements.— Ten specimens were selected to
show the relationship between number of chambers
and test volution in Globigerina bulloides bulloides
(Figure 12). G. bulloides bulloides exhibits a rather
distinctive growth pattern among planktonic species,
averaging slightly fewer (11) total number of cham¬
bers and having fewer (between three and four)
Table 3. —Sizes and chamber numbers of ten specimens of
Globigerina bulloides bulloides
Range
Mean
Maximum diameter (mm)
0. 25-0. 40
0. 32
through peripheral whorl
Maximum diameter (mm) less
0. 09-0. 19
0. 13
peripheral whorl
Ratio of diameters of peripheral
2. 8-2. 1
2. 5
whorl and rest of test
Total number of chambers
9-12
11. 10
Number of chambers in
3. 5-3. 9
3. 8
peripheral whorl
Number of chambers in
2. 9-4. 7
3.9
preperipheral whorl
20
chambers in the peripheral whorl than do many
species. All chambers are contained in within two to
three test volutions. In the early volutions there is
high variability in chamber addition with respect to
test volution, but the variability decreases markedly in
the pre-peripheral whorl.
Distribution.— Globigerina bulloides, sensu lato is
represented in all Atlantis 77-13 samples, but seldom in
large numbers. Its maximum development is in cold
water, especially sample 32, where 29 percent of the
assemblage was referred to G. bulloides falconensis.
No obvious different distribution pattern exists be¬
tween the two subspecies, G. bulloides bulloides and
G. bulloides falconensis. In Atlantis 77-9 samples, G.
bulloides, sensu lato dominated at five of the eleven
stations.
Globigerina bulloides falconensis Blow
Plate 1: figure 4
Globigerina falconensis Blow, 1959, p. 177, pi. 9: figs. 40,
41.—Parker, 1962, p. 224, pi. 1: figs. 14, 16-19.
This subspecies tends to be smaller than the subspecies
bulloides and has a constricted aperture. Of the re¬
duced final chamber and more lobulate periphery,
considered characteristic by Parker (1962, p. 224)
in differentiating Globigerina falconensis from G.
bulloides, the latter character appears too variable
among the present specimens to be taxonomically
significant, and neither seems characteristic of North
Atlantic populations here referred to this taxon.
Populations from the Pacific referred to G. falconensis
by F. L. Parker and kindly showed to the junior
author by her, differ from those here referred to
G. bulloides falconensis, however. Their chambers do
not increase so rapidly in size in the peripheral whorl
and thus their outline differs. Two taxa may
be represented.
Among the present specimens, there are usually
between three and four chambers in the peripheral
whorl. The earliest peripheral whorl chamber is much
smaller than the other three. In the Atlantis II
material the subspecies falconensis is completely grada¬
tional to the subspecies bulloides. Specimens with
three chambers almost completely occupying the
peripheral whorl closely resemble some immature
Globigerinoides trilobus in growth plan.
Insofar as we are able to determine from examina¬
tion of type-specimens, the relatively small forms with
SMITHSONIAN CONTRIBUTIONS TO PALEOBIOLOGY
relatively constricted apertures associated with and
previously included in Globigerina bulloides (see
Cifelli, 1965, p. 11, pi. 1: fig. 2) are identical with
G. bulloides falconensis of this report. As in our ma¬
terial these forms intergrade, we propose to treat G.
falconensis as a subspecies of G. bulloides.
Perhaps it should be emphasized at this point that
subspecies as used here refer to populations not to
forms or specimens. Most of our populations show
considerable variation and include mixtures of
bulloides and falconensis, although one or the other
usually clearly dominates. We assign populations ac¬
cording to which form is the most abundant. Thus,
Globigerina bulloides falconensis includes those popu¬
lations where over half of the individuals are recog¬
nizable as falconensis.
In the present material, a major differentiation
problem exists between Globigerina bulloides falconen¬
sis and Globigerinita glutinata, and it is possible that
some workers would include many of our specimens in
G. glutinata. A gradation occurs between shiny,
smooth-surfaced forms with extraumbilical silt-like
apertures and three chambers in the peripheral whorl
(morphologically like mature Globigerinoides trilobus
trilobus but smaller and smoother) and forms with
rather opaque, finely hispid walls and with umbilical
apertures which, while not as rounded as those char¬
acteristic of Globigerina bulloides are less silt-like than
usual for Globigerinita glutinata. With assemblages
from some stations only an almost arbitrary separation
is possible between G. glutinata and Globigerina bul¬
loides falconensis. In these assemblages characteristic
Globigerinita glutinata is poorly developed, although
some specimens appear to belong to that taxon. It is in¬
teresting, however, that where G. glutinata is well
developed, as at stations 8 and 13, few forms referrable
to Globigerina bulloides falconensis occur and the two
groups are fairly distinct.
Occasionally, differentiating G. bulloides falconensis
and Globigerinita glutinata from relatively smooth or
shiny immature specimens of Globigerinoides ruber and
G. trilobus poses problems. For further discussion of
the G. glutinata problem, see page 35. Globigerina
rubescens, rare in the present assemblages, has more
spherical chambers than G. bulloides falconensis and
chambers which in the peripheral whorl, tend to be of
approximately the same size instead of increasing
markedly in size. The aperture of G. rubescens also is
more arched and the average size less than that of
characteristic G. bulloides falconensis.
NUMBER 4
21
Globigerina dutertrei d’Orbigny
Plate 2: figures 1, 2
Globigerina dutertrei d’Orbigny, 1839a, p. 84, pi. 4: figs.
19-21.-—? Brady, 1884, p. 601, pi. 81: fig. 1.—Banner and
Blow, 1960a, p. 11, pi. 2: fig. 1.—Cifelli, 1965, p. 12, pi. 2:
figs. 1, 2.
Globigerina dubia Egger.—Brady, 1884, p. 595, pi. 79: fig. 17.
Globigerina eggeri Rhumbler, 1901, p. 19, fig. 20.—Phleger,
Parker, and Pierson, 1953, p. 12, pi. 1: figs. 11, 12.—
Parker, 1958, p. 277, pi. 5: figs. 5, 7.—Be, 1959, pi. 2:
figs. 1-3.—Bradshaw, 1959 [part], p. 35, pi. 6: figs. 5, 10
[not 8, 9].
Globoquadrina dutertrei (d’Orbigny).—Parker, 1962, p. 242,
pi. 7: figs. 1-13, pi. 8: figs. 1-4.
Fully developed specimens are distinctive and easily
recognizable. They have a large, open umbilical aper¬
ture, with some development of umbilical teeth and
greater number of chambers and degrees of volution
than is usual among globigerinids. (The open umbili¬
cus is found much more frequently among water-
column than bottom-sediment specimens.) Globigerina
dutertrei, however, is highly variable and less fully
developed forms may closely resemble both G. in-
compta and forms here referred to as G. aff. G.
pachyderma. The relationship of G. dutertrei with the
latter two species still remains obscure and consider¬
able differences in opinion exist among workers as to
synonomies and morphologic limits.
Questioned are how many taxa are actually repre¬
sented by the G. dutertrei-G. incompta-G. pachyderma
(or G. aff. G. pachyderma) complex and whether G.
incompta is a life stage of either of the other two. From
our study of the Atlantis 77-13 and -9 material, we
believe that G. dutertrei, G. incompta, and G. aff. G.
pachyderma represent three separate taxa. We will
present most of our arguments here, under discussion
of G. dutertrei. (Bottom-sediment speciments present
similar and possibly more complex problems, but they
are not discussed per se here.)
Largely, we base our conclusions on differences in
development, treated under ontogenies and measure¬
ments. Because the problem is intricate, some redun¬
dancy is inevitable, but perhaps will emphasize the
reasons for our treatment of these forms. We will start
with general remarks on problems and resemblances
and differences among these forms.
Both Parker (1962, p. 224) and Be and Hamlin
(1967, p. 96) consider G. incompta fully synonomous
with G. pachyderma. Be and Hamlin regard G.
incompta as immature G. pachyderma, while Parker
considers the differences between the latter two forms
and G. dutertrei sufficient to place them in separate
genera and subfamilies. (Parker, 1968 personal com¬
munication, presently is inclined to view G. incompta
as more closely related to G. dutertrei and possibly a
form of that species.) Yet, considerable similarity exists
between G. incompta and G. dutertrei. When G.
incompta was first described, it was compared mainly
with G. dutertrei (Cifelli, 1961). A number of forms
in the literature identified as G. dutertrei compare fav¬
orably or are identical with G. incompta.
According to Parker (1962, p. 242), one of the more
distinctive features of G. dutertrei (Globoquadrina
dutertrei of Parker) is the “pitted” wall surface. We
have noted this “pitted” surface. The “pits” are rather
angular and appear to represent open spaces above
pores and to be surrounded by discontinuous ridges
that look like small papillae joined together. Among
the small, ridge-like papillae are a few higher, angular,
spinose-appearing projections. For the most part, the
ridge-like papillae are continuous around the pore area,
but on a single specimen they may range from com¬
plete continuity, forming a joined network, to a dis¬
continuous ridge, to isolated, discrete papillae. In
Globigerina incompta the papillae tend to be more
discrete, and in some cases spines protrude from the
angular projections. Some tendency, however, exists
for papillae to fuse around the pore area, resulting in
a surface texture very similar to that of G. dutertrei.
Therefore, distinction between the two species cannot
always be made based on surface texture.
The wall of G. aff. G. pachyderma is coarser, with a
sugary texture, especially in the early stages, and it
tends to greatly obscure the earlier chambers. Basically,
however, it seems of the same texture, except that the
papillae are thicker, more angular, and less regularly
arranged. Actually, the fine details of the wall of all
species are difficut to ascertain under the light micro¬
scope. Textural appearance varies with lighting and
state of preservation of specimens. Detailed examina¬
tion with an electron scanning microscope will be
necessary to determine the nature of these fine
structures.
Smaller individuals of G. dutertrei with fewer than
average chambers and relatively large final chambers
closely resemble, and are sometimes difficult to dis¬
tinguish from, G. incompta (Cifelli, 1961). We base
our separation mainly on the aperture, which tends to
be more centrally located and larger in G. dutertrei
(from the water column). In G. dutertrei the arrange-
22
ment of chambers is less regular and the outline more
elliptical. Therefore, we do not believe that G.
incompta is an immature stage of G. dutertrei. In the
Atlantis 77-13 samples G. incompta was found in
large numbers and associated with but few typical
forms of G. dutertrei; we believe this supports our
contention of two distinct forms.
Smaller forms of G. dutertrei also closely resemble
fully developed G. aff. G. pachyderma. The latter
taxon, however, has a much more constricted aperture
that lacks umbilical teeth. The coarse, sugary wall tex¬
ture and nature of the reduced final chamber, when it
is present, also serve to distinguish G. aff. G. pachy¬
derma. G. dutertrei from the water column may also
have reduced final chambers but they do not tend to
be bulla-like as do those of G. aff. G. pachyderma. The
difference in wall texture between (1) G. aff. G.
pachyderma and (2) G. dutertrei and G. incompta is
particularly evident in the early stages, as is the dif¬
ference in amount of depression of sutures, with G. aff.
G. pachyderma showing relatively little depression.
Ontogenies. —Specimens we believe to represent
ontogenetic stages of G. dutertrei, G. incompta, and G.
aff. G. pachyderma are illustrated in Figures 13, 14,
and 15, respectively. Unfortunately, line drawings can¬
not reveal adequately ontogenetic differences in wall
texture, a feature considered a clue to separation of
this complex of species; however, the illustrated speci¬
mens are in the National Museum of Natural History
collections and are available for examination.
Early stages of G. dutertrei have thin, mostly smooth,
shiny walls with small, discrete papillae. During growth,
the wall becomes thicker and coarser. The papillae
appear to coalesce, forming the partially continuous
ridges encircling the depressions containing the pores.
Though degree of coalescence varies, it is not complete,
even in the adult. Occassional fully developed speci¬
mens exhibit a final chamber with a thin, smooth, dis¬
cretely papillate wall like those of earlier stages of
ontogeny.
In G. incompta, the very early stages show a wall
that is thicker and has larger and more discrete papillae
than are usually seen in equally immature G. dutertrei.
During growth, the wall of G. incompta tends to follow
a similar pattern of coalescence of papillae as occurs in
G. dutertrei, except that the coalescence begins earlier
in the ontogeny and is less well developed in G. in¬
compta, leaving many more discrete papillae in the
adult form. Thus, the textural pattern of pits and ridges
SMITHSONIAN CONTRIBUTIONS TO PALEOBIOLOGY
characterizes both G. dutertrei and G. incompta,
though it is less pronounced in the latter, and some
morphologic overlap occurs.
In G. aff. G. pachyderma the ontogenetic textural
trend appears just the reverse of that of the two other
species. In early stages the wall is extremely thick and
coarse, with a sugary texture. The surface is irregular
and some spinose and angular papillae can be seen,
but for the most part structural details of the texture
are difficult to determine. Late in the ontogeny, usually
in the last three or four chambers, the wall becomes
thinner and the surface more regular. Papillae become
more distinct and a pattern of partially coalescent
ridges surrounding depressed pore areas can be seen.
This pattern bears close resemblance to that of G. in¬
compta and also some forms of G. dutertrei in which
the papillae are less typically coalesced. The G. aff.
G. pachyderma wall, however, remains coarser than
that of G. incompta, with less regularly shaped papillae
that also tend to be more spinose. Thus, while the adult
wall of G. aff. G. pachyderma closely resembles that of
G. incompta and some forms of G. dutertrei, a distinct
difference exists in the early stages and some differ¬
ences can be seen in the mature forms.
The aperture of G. dutertrei closely resembles that
of G. incompta in the early stages. Both apertures are
at the base of the final chamber and are umbilical-
extraumbilical or extraumbilical but do not reach the
periphery. In G. aff. G. pachyderma, the aperture is
relatively small and consistently umbilical-extraumbili-
cal, with the maximum dimension always confined to
the umbilical region.
During ontogeny, the aperture of G. incompta re¬
mains constant in both position and relative size. In
G. dutertrei (from the water column) the aperture
becomes more consistently umbilical and relatively
larger and more open early in the ontogeny. This
change towards an open umbilical aperture in G.
dutertrei relates to ontogenetic coiling change and the
relatively small size increase of later chambers, which
tend to encircle and maximally disclose the umbilicus.
In G. aff. G. pachyderma the aperture remains essen¬
tially constant during ontogeny except that it becomes
more incised because of increased lobulation of the
later chambers.
Thin apertural lips occur throughout the ontogenies
of both G. dutertrei and G. incompta. During growth
of G. dutertrei, however, some lips develop single,
tooth-like lobes (Figures 13d, e, f) . In G. aff. G. pachy-
NUMBER 4
23
Figure 13-15. Comparison of the growth patterns and general morphology of three taxa:
13, Globigerina dutertrei; 14, G. incompta; 15, G. aff. G. pachyderma.
derma thin lips are not present in early stages but some- at which they occur, in most cases, with a few in the
times appear in later stages. The edge of the aperture fully developed stage being thinner than the rest of the
may be jagged because of the coarse, sugary, irregular peripheral whorl chambers.
texture of the wall. Also, in both early and late stages Both G. dutertrei and G. incompta begin as flat, com-
there may appear partially or completely developed pressed coiled forms. G. incompta , in the very early
bullae, ranging to reduced final chambers. The wall stages, is particularly flattened on the spiral side and
texture of these bullae or reduced final chambers cor- is globorotalid in appearance (Figure 14a). Coiling be-
responds with that of the particular ontogenetic stage comes more conical during growth in both species, but
24
change is more noticeable in G. dutertrei, where the
later chambers encircle the large, open umbilicus (Fig¬
ure 13). This encircling and apertural size also relates
to the fact that many, though far from all, specimens
of G. dutertrei show little chamber size increase be¬
tween the final two or three chambers. In G. aff. G.
pachyderma early stage coils are flattened, although
not nearly as compressed as in the other two taxa. The
later stages show a slight tendency to become conically
coiled, but this tendency is considerably less than in
G. dutertrei. Related to coiling, though probably in
different ways for the different taxa, is that both G.
dutertrei and G. aff. G. pachyderma show the exact
same number of chambers in the peripheral whorl on
both spiral and umbilical sides, while G. incompta
tends to show slightly fewer on the umbilical than spiral
side.
SMITHSONIAN CONTRIBUTIONS TO PALEOBIOLOGY
Throughout the ontogeny of G. dutertrei and G.
incompta, the lobulation of the periphery and inden¬
tation of sutures remain relatively constant. By con¬
trast, the early stages of G. aff. G. pachyderma exhibit
relatively little indentation of sutures. In later stages
lobation and indentation increases markedly and adults
thus closely resemble G. incompta (Figures 14, 15).
Measurements.— The relationship between num¬
ber of chambers and degrees of volution in G. dutertrei
is shown in Figure 16. Among all the globigerinids, this
species shows the greatest range both in total number
of chambers and degrees of whorl. The maximum num¬
ber of chambers recorded is 19 and the minimum 10.
These chambers are contained in between 650° and
1300° of whorl. Four of the 25 specimens measured
(see Figure 16) reach more than 1080° (three full
whorls) and have 17 or more chambers. Over half the
18
16
IT)
■=>
Z
2
10
(D
m
Ll)
CD
2 8
<
X
a
2
-
1.
2. *
■
-
6.
-
7 J
PERIPHERAL WHORL
-
16
• *•+* *
- v- . ••."
71
23..
*• • * *■+ ***•*!•* *
-
25
* *;•
25 ....
25
-
25
25.
25 * ——— —
■
Globigerina dutertrei
7S
( 25 SPECIMENS)
0
25, • •*••*«%•*** <
D
SJ 0
-
0
0
. 25._
_i_i_i_1_1_1_i. .1 -J_1_1 1 1_L
O
-1 1—J-1-1 1 1 1 1_1 1_L_1_1
J—I—1 1 1—1—1—1—1- 1 1_1 1 » ■
_l_1—._1_l_J_1_1_l_i_1_1_l
100 200 300 400 500 600 700 800 900 1000 1100 1200 1300
NUMBER OF DEGREES OF WHORL
Figure 16 .—Globigerina dutertrei. Growth pattern expressed as the relationship between number
of chambers and number of degrees of whorl for 25 specimens. The measurement increase on
both axes goes from the final chamber inward, not from proloculus outward.
NUMBER 4
25
specimens reach two and a half full whorls with 13 or
more chambers.
The number of chambers in the peripheral whorl of
G. dutertrei varies and ranges from approximately
three and a half to five and a half, with an average of
approximately four and a half. In the volution between
360° and 720° (preperipheral whorl) there are slightly
more chambers, ranging from approximately four and
a half to six, with an average of approximately five.
This tendency towards slight decrease in rate of cham¬
ber addition with respect to volution in the peripheral
whorl seems to characterize most globigerinids.
If the specimens measured may be considered repre¬
sentative of populations as a whole, some differences
can be seen between G. dutertrei, G. incompta, and
G. aff. G. pachyderma (Figures 16, 17, and 19). First,
G. dutertrei shows a greater tendency toward both a
greater total number of chambers and degrees of whorl.
As the average G. dutertrei is larger, this is not unex¬
pected, but is not a necessary correlate with size. In
the peripheral whorl the number of chambers varies
from between three and four to between five and six.
G. incompta and G. aff. G. pachyderma peripheral
whorl chamber-numbers are more constant, between
four and five.
A notable difference between G. dutertrei and G.
incompta exists in the variability in rate of chamber
addition. In G. dutertrei this variation is relatively con¬
stant throughout ontogeny. In G. incompta, however,
high variability occurs among specimens in the earlier
volutions and decreases rather suddenly toward the
end of the pre-peripheral whorl; in the peripheral
whorl the rate of chamber addition is remarkably
constant. For example, at chamber 12 of G. incompta
(Figure 17) the spread in amount of whorl is about
225°, while at chamber one it is only about 25°. In
G. aff. G. pachyderma the pattern of variability in rate
of chamber addition is relatively constant, as in G.
dutertrei. While, however, the rate of chamber addi¬
tion among specimens is relatively constant, it varies
considerably in the ontogeny of individual specimens.
Unfortunately, this is not shown in the chamber addi¬
tion figures as it is not possible to portray individual
ontogenies by connecting points with lines without
obscuring the general pattern of the figures.
These figures illustrate that G. dutertrei tends to
have a larger number of chambers, although the mean
falls within the range of both G. incompta and G. aff.
G. pachyderma. The maximum numbers of chambers
of G. aff. G. pachyderma cannot be determined with
certainty in most cases as the early chambers are mostly
obscured. The data suggest, however, that G. aff. G.
pachyderma tends to average at least one more cham¬
ber than G. incompta.
Table 4. —Suites of specimens selected to determine differences in numbers of chambers among
G. dutertrei, G. incompta, and G. aff. G. pachyderma
G. dutertrei
G.
incompta
G. aff. G.
pachyderma
Atlantis II -13 station
9
34
36
36
Number of specimens
Number of chambers
35
19
25
8
Range
10-19
9-15
10-15
12-15
Mean
Number of chambers in pe¬
ripheral whorl
13. 91
11.89
12. 16
12. 75
Range
Mean
Number of chambers in pre¬
peripheral whorl
3. 8-5. 5
4. 4
4. 0-5. 0
4. 48
4. 0-4. 5
4. 34
4. 0-5. 0
Range
Mean
4. 4-6. 1
5. 1
4. 0-7. 0
5. 07
4. 5-6. 5
5. 34
4. 5-6. 7
26
SMITHSONIAN CONTRIBUTIONS TO PALEOBIOLOGY
Table 5. —Suites of specimens selected randomly for a comparison of maximum diameters of
Globigerina dutertrei, G. incompta, and G. aff. G. pachyderma
G. dutertrei
G. incompta
G. aff. G.
pachyderma
Atlantis 11 —13 Station
9
34
36
36
Number of specimens
36
43
40
37
Range of maximum diameters
0. 20-0. 58
0. 16-0. 36
0. 18-0. 35
0. 20-0. 35
(mm)
Mean maximum diameters (mm)
0. 3725
0. 2665
0. 25475
0. 2670
Variance
0. 01365
0. 00250
0. 00242
0. 00118
Globigerina dutertrei has the greatest range and
largest mean of maximum diameters. The ranges of the
other two taxa fall virtually within and at the low-size
end of G. dutertrei. Mean sizes of G. incompta and G.
aff. G. pachyderma are virtually identical. The vari¬
ance of G. dutertrei is the greatest and that of G. aff. G.
pachyderma least. The variances of the two populations
of G. incompta are very similar.
The F test (see Natrella, 1963) at the 95-percent
level was used to determine whether any significant
differences between the variances of the taxa exist. The
tests showed that there are significant differences be¬
tween the variances of the three taxa. Further, no
significant difference exists between the two popula¬
tions of G. incompta.
All specimens of G. dutertrei observed are right
coiled.
Distribution. —Specimens of G. dutertrei occur in
almost every sample of the Atlantis 77-13 traverse and
in four from the Atlantis 1 7-9 traverse, but in small
numbers. The maximum frequency of this species is 6
percent, found at station 9. At Atlantis 77-13 stations,
when G. incompta is 8 percent or less, G. dutertrei is
less than 5 percent (except at station 9). It is, however,
more abundant than where G. incompta exceeds 8
percent. There G. dutertrei usually is 1 percent or less,
although totally absent at only two stations (34, 42).
At Atlantis 11-9 stations, on the other hand, G. duter¬
trei is present only where G. incompta is relatively
abundant (four stations).
Globigerina incompta Cifelli
Plate 2: figure 3
Globigerina eggeri Rhumbler.—Bradshaw, 1959 [part], p. 35,
pi. 6: figs. 8, 9 [not 5, 10].
Globigerina incompta Cifelli, 1961, p. 84, pi. 4: figs. 1—7.
Globigerina pachyderma incompta Cifelli.—Cifelli, 1965
[part], p. 11 [not pi. 1: figs. 4, 6].
The ways in which this species may be distinguished
from Globigerina dutertrei and G. aff. G. pachyderma
are discussed under G. dutertrei. In a previous paper
(Cifelli, 1965, p. 11), G. incompta was treated tenta¬
tively as a subspecies of G. pachyderma. This was done
because Parker (1962, p. 224) reported that the forms
are gradational in Pacific bottom sediments, and some
gradation appeared to exist in North Atlantic slope
waters. From detailed studies of Atlantis 77-13 and -9
and other North Atlantic plankton tows, however, it
now seems unlikely that such a gradation exists—at
least not in the temperate North Atlantic surface wa¬
ters. Our studies indicate that the close resemblance
between adult G. incompta and G. aff. G. pachyderma
of this study is the result of ontogenetic convergence
(see p. 22 under G. dutertrei ). In the material we have
studied, G. incompta and G. aff. G. pachyderma are
distinct, although sometimes difficult to distinguish,
particularly when G. incompta has a reduced final
chamber.
The closest affinities of G. incompta seem to be
with G. dutertrei. While fully developed forms of G.
dutertrei, with large, open umbilical apertures and
relatively numerous chambers are easily distinguished,
earlier stages of this species are less distinctive and
some morphologic overlap with G. incompta occurs.
The overlap is slight, however, and we have found
no trouble in assigning the majority of our specimens
to one or the other species. In spite of this overlap,
we would hesitate at this time to treat them as con-
specific subspecies. The relations of the G. dutertrei-G.
NUMBER 4
27
imcompta-G. pachyderma complex are still obscure
and it is possible that these forms exhibit different
morphologic development in areas outside of the tem¬
perate North Atlantic.
Very early stages of G. incompta have a distinctly
globorotalid aspect, being flat on the spiral side, with
a low trochospiral coil and have an aperture located
extraumbilically, along the base of the final chamber.
These small forms resemble some young stages of G.
infiata which are coarsely hispid, a character more
prominent, however, in very early stages of G. in¬
compta. We have encountered no difficulty separating
G. incompta from G. quinqueloba egelida, new sub¬
species, in the present material. Among the seemingly
intergrading populations of taxa from the Labrador
Sea and Arctic plankton we have examined, however,
forms referable to both G. incompta and G. quin¬
queloba egelida, as well as other taxa, occur and sepa¬
rations among taxa can be most difficult.
Measurements. —Ten specimens of G. incompta
were selected to determine the relationship between
chamber number and degrees of volution (Figure 17).
For these 10, the maximum chamber number is 15
and the minimum 10, but the majority have 12. In
all but one specimen, the chambers occupy between
two and three full volutions, with a maximum of 1050°
of whorl. In the peripheral whorl, the number of
chambers ranges between slightly less than four to five.
In the previous whorl the number of chambers ranges
from between four and five to between six and seven.
Chamber addition with respect to degrees of volu¬
tion is consistent among specimens in the peripheral
whorl, but in the earlier volutions considerable vari¬
ability and a wide spread of points exist (as mentioned
previously). In this respect, G. incompta resembles
G. bulloides bulloides (Figures 12 and 17). Within the
peripheral whorl consistency, a common tendency for
the third chamber measured to occupy more degrees
of whorl than the second or fourth may be noted.
I » I L I 1 » « I » I ' I I » ■ ■_I_ 1 1 1 *_ I _ I _ I _ I _1- I -1-1-1-1-1-1- 1 -1- 1—1 -1-1— I - 1 - L
100 200 300 400 500 600 700 800 900 1000 1100
NUMBER OF DEGREES OF WHORL
Figure 17 .—Globigerina incompta. Growth pattern expressed as the relationship between number
of chambers and number of degrees of whorl for 10 specimens. The measurement increase on
both axes goes from the final chamber inward, not from proloculus outward.
28
Table 6. —Sizes of the ten specimens of Globigerina
incompta shown in Figure 17
Range
Mean
Maximum diameter (mm)
0. 18-0. 33
0. 26
through peripheral whorl
Maximum diameter (mm) less
0. 06-0. 14
0. 095
peripheral whorl
Ratio of diameters of peripheral
whorl and rest of test
3. 0-2. 4
2. 7
Maximum diameters and chamber numbers of an
additional number of specimens from two stations
were measured and compared with those of G. duter-
trei and G. aff. G. pachyderma (Tables 4, 5). All speci¬
mens observed are right-coiling.
Distribution. — Globigerina incompta is present in
almost every assemblage studied. It constitutes less than
10 percent of the assemblages in many samples of the
Atlantis 77-13 traverse but reaches 16 percent in sam¬
ple 4, 32 percent in sample 32, and 64 percent, 72 per¬
cent, 62 percent, 55 percent, and 44 percent in samples
34, 36, 38, 40, and 42, respectively. In the Atlantis 77-9
samples, G. incompta constitutes more than 10 percent
of four assemblages, 6 of one, and less than 5 percent
of four.
Globigerina inflata d’Orbigny
Plate 2: figures 4, 5
Globigerina inflata d’Orbigny, 1839b, p. 134, pi. 2: figs.
7-9.—Phleger, Parker, and Pierson, 1953, p. 13, pi. 1: figs.
15, 16.—Parker, 1958, p. 277, pi. 6: fig. 3.—Be, 1959, pi.
1: figs. 12-14.—Bradshaw, 1959, p. 36, pi. 6: figs.
16-18.—Cifelli, 1965, p. 14, pi. 4: figs. 1-3.
Globorotalia inflata (d’Orbigny).—Parker, 1962, p. 236, pi.
5: figs. 6-9.
This species varies considerably in chamber inflation
and apertural character. Normally there are four cham¬
bers in the peripheral whorl, but some individuals, par¬
ticularly among small immature ones, contain three
or five. Large inflated forms often strongly tend to¬
wards peripheral rounding and streptospiral coiling in
the final whorl. Rarely the final chamber is reduced.
The aperture usually is umbilical-extraumbilical but
may be extraumbilical or, more rarely, umbilical, and
SMITHSONIAN CONTRIBUTIONS TO PALEOBIOLOGY
varies considerably in height. Where the last chamber
is streptospirally arranged, as proves to be the case with
most specimens upon close inspection, the aperture is
oblique to the suture between the first two chambers
of the peripheral whorl. Some specimens of this type
closely approach Pulleniatina in their coiling. In fully
trochospiral specimens with four chambers in the peri¬
pheral whorl, the aperture is approximately perpendic¬
ular to the suture between the two earliest chambers
of the peripheral whorl. Normally, high, large aper¬
tures are associated with forms with inflated chambers;
lower more restricted (although still large) apertures
characterize forms with acute peripheries.
As previously noted (Cifelli, 1965, p. 14), the closest
morphologic affinities of this species appear to be with
Globorotalia punctulata (of Cifelli, 1965), the differ¬
ence being chiefly in the degree of chamber inflation
and concomitant peripheral sharpness and in the aper¬
tural height. (See Cifelli, 1965 for discussion of the
generic placement of Globigerina inflata and related
problems.) Although the characters are variable, we
have not observed a complete transition between the
forms. Complete certainty of identity, however, is not
always possible with some small, immature individuals.
These tend to have relatively acute peripheries; many
also have low, restricted umbilical-extraumbilical aper¬
tures, although some have rather rounded umbilical
apertures. A marked bend in the ventral sutures char¬
acterizes some of these small specimens. The numbers
of these small problematic specimens usually are sig¬
nificantly smaller than those of more characteristic
Globigerina inflata, but in sample 13 they occur almost
as abundantly. A comparison of the variational pat¬
terns between Globigerina inflata and Globorotalia
punctulata is shown in Figure 18.
Distribution. —Globigerina inflata is well repre¬
sented in the Atlantis 77-13 traverse assemblages, be¬
ing present at every station, ranging in relative abun¬
dances from 2 to 34 percent. The small forms which
morphologically also approach Globorotalia punctulata
but are taxonomically referred to Globigerina inflata
are present in most samples in abundances of from less
than 1 to 4 percent. In the Atlantis 77-9 samples Glo¬
bigerina inflata (including the small form) is very
abundant. It is present in all samples, constituting
more than 10 percent of every assemblage but one, and
20 percent or greater in all but three, reaching a maxi¬
mum of 75 percent in sample 288.
NUMBER 4
29
Figure 18. —Comparison between and growth series of ( g-a ) Globorotalia punctulata and ( h—t )
Globigerina inflata. Note similarity between species of some immature individuals.
Globigerina megastoma Earland
Plate 3: figure 1
Globigerina megastoma Earland, 1934 (1935), p. 177, pi. 8:
figs. 9-12.
Two specimens apparently referable to this species
were found in the sample from station 5. They are
quite distinct from any other forms found in the At¬
lantis II assemblages. Although not as large (0.34
mm maximum diameter as compared with 0.60 mm
given by Earland) as Earland’s form from the South
Atlantic, these two specimens compare well in having
a very thin, fairly smooth wall, a highly trochoid spiral
test, chambers greatly inflated and rapidly increasing
in size with slightly more than four but not five com¬
plete chambers in the peripheral whorl, and quite
depressed sutures. The nature of the aperture of the
present two specimens may differ somewhat from that
described by Earland but precise comparison is diffi¬
cult on the basis of the figures. Earland (1934, p. 177)
states that the aperature, “situated on the inner edge
of the final chamber is large and semicircular, with a
reverted lip.” The apertures of the present specimens
extend from the umbilical area outward around the
periphery to the spiral side of the test. They are large
but not semicircular, being rendered rather subrec-
tangular in outline by their position and the presence
of an outward-protruding lip across their upper
margin, which actually compares favorably with
Earland’s figures.
To our knowledge this is the first record of this
species in the plankton. It may have been overlooked
in the past because of the test’s frangibleness. The
specimens’ appearance, especially the aperture, also
suggests that they could be immature individuals of
some other planktonic taxon, but none occurring in
our material.
Globigerina aff. G. pachyderma (Ehrenberg)
Plate 3: figures 2, 3
Globigerina pachyderma incompta Cifelli.—Cifelli, 1965
[part], p. 11, pi. 1.: figs. 4, 6.
Test trochospirally low, rounded to lobate; chambers
subangular to subcircular, numbering approximately
30
12-13 in test, but so obscured in early volution as to be
indeterminate on most specimens, with four to five
chambers in peripheral whorl, exact number depend¬
ing on final chamber size; chambers in peripheral
whorl of almost equal size except final chamber which
may be reduced; aperture small, umbilical-extraum-
bilical but mostly umbilical with slit-like extension
towards periphery, often partially overlapped by re¬
duced final chamber or bulla; wall thick, coarse with
surgary texture, hispid, ridged, and pitted; sutures
radial, flush in early part to depressed in peripheral
whorl, mostly obscure on early chambers; coiling to
the right.
The specimens included here bear the most re¬
semblance to Globigerina pachyderma of any we have
observed in North Atlantic plankton. The resemblance
is closest among the small, not fully developed in¬
dividuals. These are characterized by extremely com¬
pact tests with thick walls, which obscure early
chambers, by silt-like apertures whose maximum
dimensions are centrally located, and by four chambers
in the peripheral whorl. Except for the fact that they
are on the average smaller, they compare favorably
with G. pachyderma observed in bottom sediments
from the Arctic and Antarctic regions. The larger,
more fully developed specimens, however, become less
compact, with the aperture umbilical-extraumbilical
and more open, though partly obscured by the down¬
ward extension of the final chamber. They also usually
have a less coarsely surfaced, although still sugary-
appearing wall in the latter part of the test. There
are between four and five chambers in the peripheral
whorl. Where a full fifth chamber appears in the peri¬
pheral whorl, it is much reduced in size, and sometimes
bulla-like. Adult specimens closely resemble and can
be confused with G. incompta, as was done by Cifelli
(1965, p. 11, pi. 1: figs. 4, 6) with the two specimens
he figured as variants of G. incompta. They are dis¬
tinguishable, however, from G. incompta and G.
dutertrei, which they also resemble, mainly on their
ontogenetic development which is discussed under G.
dutertrei (p. 22).
In contrast, a suite of specimens from Pacific bottom
sediments kindly sent us by F. L. Parker includes forms
comparable to mature Globigerina aff. G. pachy¬
derma and to mature G. dutertrei. Further, specimens
from Atlantic bottom sediments show transition be¬
tween forms referable to G. dutertrei and G. aff. G.
pachyderma, although these forms are not identical to
SMITHSONIAN CONTRIBUTIONS TO PALEOBIOLOGY
our water-column specimens. No clear division be¬
tween either the Pacific or Atlantic bottom sediment
forms could be made. They seemingly represent tran¬
sitional series and it might therefore appear that G.
aff. G. pachyderma of this report is an immature form
of G. dutertrei. Further, the junior author has seen a
few specimens at Scripps Institution of Oceanography
that were collected from the water column in the
Pacific. These specimens are definitely referable to
“typical” G. pachyderma and they occur in associa¬
tion with G. dutertrei. We have no explanation for
the apparent differences in relationships of these two
water-column groups between the Atlantic and Pacific,
nor for the differences between the transitional series
from the two oceans. Possibly, G. pachyderma and
G. dutertrei are polyphyletic groups. On the basis of
the Atlantic water-column material that we have ex¬
amined, however, the taxa are discrete and we prefer
to retain them until relationships are clarified.
Perhaps the chief problem with Globigerina pachy¬
derma is that while it dominates bottom planktonic
faunas in the Arctic and Antarctic regions, comparable
assemblages mainly are of doubtful occurrence or
absent in the plankton. It is possible that they live
mainly in water deeper than normally sampled. Ac¬
cording to Be (1960a) forms with G. pachyderma
morphology do not occur in Arctic surface waters.
In G. aff. G. pachyderma of this report, the forms most
comparable with G. pachyderma, forma typica, con¬
stitute but small percentages of the populations.
To account for the apparent absence of Globigerina
pachyderma, forma typica, in surface waters, Be con¬
cluded that the G. pachyderma morphology is achieved
after the individuals sink below 200 meters, where addi¬
tional calcite and a reduced final chamber are added.
We cannot reconcile our observations with this con¬
clusion. First, the forms from Atlantis 77-13 and -9
that are comparable with G. pachyderma come from
waters 200 meters or less deep. It may eventually prove
biogeographically significant that these waters are
temperate, not Arctic. Second, our ontogenetic inter¬
pretation is opposite to Be’s. We infer that the G.
pachyderma found is an early, rather than late, devel¬
opmental stage. Finally, Arctic plankton assemblages
we have observed are composed of a variety of forms
of difficult taxonomic placement. We find it hard to
see how many of them could assume the G. pachy¬
derma morphology by Be’s mechanism.
NUMBER 4
31
Another interpretation of the G. pachyderma prob¬
lem, one that deserves serious consideration, is that of
Uchio (1960). Uchio suggested that the G. pachy¬
derma on the Antarctic bottom were deposited some¬
time before the present and that sedimentation there
is slow. Dating of the tests by C 14 gave 5,490 (±370)
years ago.
According to D. J. Stanley (personal communica¬
tion), the bottom in the region around Nova Scotia,
particularly on the slope, and perhaps around the
Arctic region as a whole, receives little sediment and
the Pleistocene crops out near the surface. There are
also indications that the Holocene sediment exposed
may be mixed with Pleistocene. Another possibility
is that the Arctic and Antarctic cold waters act to dis¬
solve tests of species with relatively thin walls at depths
considerably less than normal calcium carbonate com¬
pensation depth. Kennett (1966) and Berger (1968),
among others, have shown that Arctic and Antarctic
bottom waters act particularly aggressively in attacking
calcium carbonate. Most of the forms we have ob¬
served in Arctic plankton have relatively thin walls,
so perhaps most dissolve before, or shortly after reach¬
ing the bottom. In summary, it is worth considering that
assemblages of G. pachyderma, sensu stricto, observed
on the bottom are extinct or near extinct, and that G.
aff. G. pachyderma is a descendant subspecies.
Measurements. —The relationship between cham¬
ber number and test volution of six specimens of
Globigerina aff. G. pachyderma is shown in Figure 19.
The coarse wall surface obscures chambers in early
volutions and the exact total number clearly shows
on only two of the six specimens. For this reason,
queries are placed at the initial volutions in Figure 19.
The recorded maximum number of chambers on any
specimen is 14, but probably the actual maximum is
not much greater, since the wall totally obscures only
a minute portion of the test.
Chamber addition in this species appears relatively
consistent throughout the observable part of the
I4h
o' 2
3
o
cc
CL
(/)
3
10
(T)
CC
LJ
CD
2
<
X
c_>
cc
in
0D
PERIPHERAL WHORL
5-6 ?!
1.
2 +?
4+?
6 *i& :
Globigerina aff. G. pachyderma
(6 SPECIMENS)
o
I o
10
±
o
<\l
r-
_L_J_ I li I
±
100 200 300 400 500 600 700 800
NUMBER OF DEGREES OF WHORL
900
1000
1100
Figure 19 .—Globigerina aff. G. pachyderma. Growth pattern expressed as the relationship
between number of chambers and number of degrees of whorl for six specimens. The measure¬
ment increase on both axes goes from the final chamber inward, not from proloculus outward.
32
ontogeny, more comparable, in this respect, with G.
dutertrei than with G. incompta (Figures 16, 17).
The relationship or ratio between chambers and
degrees of whorl does not vary particularly among
individuals, except as affected by the amount of reduc¬
tion of the final chamber. In this respect, G. aff. G.
pachyderma is much more consistent than either G.
dutertrei or G. incompta, although both G. aff. G.
pachyderma and G. incompta are quite consistent in
the peripheral whorl. Each chamber of the peripheral
whorl occupies about the same number of degrees
with G. aff. G. pachyderma (except reduced final
chambers) while this is not the case with G. incompta.
As with G. incompta, most specimens of G. aff. G.
pachyderma extend into but do not complete a third
whorl. All specimens of G. aff. G. pachyderma meas¬
ured fully completed their fourth chambers in the
peripheral whorl, which is not so for G. incompta or
G. dutertrei. In all specimens there are between four
and five chambers in the peripheral whorl and a
slightly greater number (about half a chamber in the
measured specimens) in the pre-peripheral whorl. The
recorded maximum number of degrees of volution in
G. aff. G. pachyderma is about 1040°; and the actual
number probably is about the same as in G. incompta.
Table 7. —Sizes of the six specimens of Globigerina off.
G. pachyderma shown in Figure 19
Range
Mean
Maximum diameter (mm)
0. 28-0. 35
0. 31
through peripheral whorl
Maximum diameter (mm) less
0. 12-0. 17
0. 13
peripheral whorl
Ratio of diameters of peripheral
2. 3-2. 1
1. 8
whorl and rest of test
These maximum diameters are slightly greater than
those of the suite chosen for comparison with G.
dutertrei and G. incompta (see p. 26). Probably this
is because of some bias towards larger specimens in
the present suite, in order to reveal maximum onto¬
genetic development.
Distribution. —Globigerina aff. G. pachyderma
occurs in small numbers in almost all Atlantis 77-13
SMITHSONIAN CONTRIBUTIONS TO PALEOBIOLOGY
samples, reaching a peak of 6 percent of the assem¬
blage at station 34. It represents less than 1 percent
and 2 percent, respectively, in two Atlantic 77-9
assemblages.
Globigerina quinqueloba egelida, new subspecies
Plate 3: figures 4, 5, 6, 7
Globigerina cf. quinqueloba Natland.—Todd and Bronni-
mann, 1957, p. 40, pi. 12: figs. 2, 3.—Be, 1959, pi. 1:
figs. 21, 22.
Globigerina aff. G. quinqueloba Natland.—Cifelli, 1965, p. 13,
pi. 2: figs. 3, 4.
Test trochospirally low with a rounded, lobate periph¬
ery, and with up to three and occasionally part of four
whorls; chambers subspherical, enlarging fairly
rapidly and at an even rate, usually with four and a
half to five in the peripheral whorl, which are visible
on both sides of the test, and averaging a total of 13
or 14 in the adult test, forming a low, conical spire
on most specimens but almost planar in others, final
chamber often itself extended or with a thin lip or
flap extending downward to partially cover the aper¬
ture, occasionally a reduced final chamber or a bulla
covering the aperture; aperture interiomarginal,
umbilical to umbilical-extraumbilical, subrounded;
sutures distinct, narrow, depressed, radial on both
sides; wall finely perforate, thin, finely hispid or
spinose but with occasional specimens having a few
coarser spines around the peripheral parts of the
chambers, sometimes in combination with a reduced
final chamber; direction of coiling about equally
divided between left and right. Maximum diameters
of holotype and paratypes 0.15-0.24 mm.
According to F. L. Parker (personal communica¬
tion) paratypes of Globigerina quinqueloba Natland
presumably deposited at the Scripps Institution of
Oceanography are not there, so that the holotype, de¬
posited at the National Museum of Natural History is
the only available primary type. The holotype of
Globigerina quinqueloba Natland resembles G. quin¬
queloba egelida, but does not fall within the range of
variation of the North Atlantic assemblages included
within this new subspecies. The chief differences are
that the test of the holotype is thicker walled, more
compact, with less depressed sutures and a less lobulate
NUMBER 4
33
Table 8.— Sizes and chamber numbers of forty specimens of G. quinqueloba egelida, new
subspecies (ten plotted on Figure 20, ten from Atlantis II -13 sample 26, and 20 from
sample 18)
Range
Mean
Station (Atlantis 77-13)
26
18
26
18
Maximum diameter (mm)
through peripheral whorl
0. 11-0. 26
0. 10-0. 19
0. 20
0. 14
Maximum diameter (mm) less
peripheral whorl
0. 06-0. 10
—
0. 08
—
Ratio of diameters of peripheral
whorl and rest of test
1.8-2. 6
—
2. 5
-
Total number of chambers
11-16
12-14
14(13. 79)
13 (12. 95)
Number of chambers in
peripheral whorl
4. 5-5. 0
4. 6-5. 0
4. 69
4. 78
Number of chambers in
pre-peripheral whorl
4. 5-5. 0
4. 2-6. 0
4. 74
4. 86
periphery. Of these differences, the only one possibly
a result of the holotype being a bottom-sediment speci¬
men is the thicker wali. Moreover, the holotype is
thicker with respect to its maximum diameter than G.
quinqueloba egelida and also appreciably larger in
maximum diameter. In G. quinqueloba egelida, the
aperture is small and either open and semicircular,
often with a thin lip, or modified and partially covered
by the final chamber which may form a flap that
obscures, but does not completely close over the aper¬
ture (bullae are seldom seen). State of preservation
of the holotype prevents determination of whether
there may be a thin lip at the base of the flap. In
contrast to G. quinqueloba egelida, however, the flap
of the holotype is a gross feature that extends across
the aperture, attaching to the chamber below, almost
completely closing over the apertural area. Most adult
specimens of G. quinqueloba egelida have a total of 13
chambers with between four and half and five in the
peripheral whorl, which is the same as the holotype of
G. quinqueloba.
Comparison between Globigerina quinqueloba
egelida, new subspecies, and G. quinqueloba, sensu
stricto, has been made from a suite of specimens from
the approximate type-locality, kindly furnished us by
F. L. Parker. This suite of specimens appears to show
a gradation between the holotype of G. quinqueloba
and G. quinqueloba egelida. As a group, the specimens
are closer to the holotype in the thicker, more coarsely
hispid and perforate wall, compactness and thickness
of test, relatively slight depression of sutures and the
pronounced apertural coverings and flaps. The ma¬
jority of specimens, however, are not as thick or as
compact as the holotype, and the holotype, therefore,
appears an end member of the populations of the
species that we have seen.
All assemblages of Globigerina quinqueloba that we
have observed in North Atlantic plankton tows are
referable to G. quinqueloba egelida, new subspecies.
Thus we include in our synonymy those figured as G.
cf. quinqueloba by Be (1969) and G. aff. G. quinque¬
loba by Cifelli (1965). The assemblages from bottom
sediments in the Gulf of Paria figured by Todd and
Bronniman (1957) as G. cf. quinqueloba are referable
to the new subspecies, as are the specimens from North
Atlantic bottom sediments figured as G. quinqueloba
by Phleger, Parker, and Pierson (1953).
The specimen figured by Bradshaw (1959) as G.
quinqueloba from Pacific plankton appears to belong
to G. quinqueloba, sensu stricto.
A close similarity exists between G. quinqueloba
egelida, new subspecies, and the subarctic planktonic
form with five chambers in the peripheral whorl re¬
ferred by many to G. pachyderma. Characteristically,
however, that form is larger and thicker than the
present specimens, has a more umbilical and more open
aperture, and a heavier wall. The relationship between
these two forms needs further investigation.
A form with a few coarser spines and reduced,
rather peculiarly shaped final chambers might repre-
34
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PERIPHERAL WHORL
SMITHSONIAN CONTRIBUTIONS TO PALEOBIOLOGY
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G/obigerina quinque/obo egelida
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100 200 300 400 500 600 700 800
NUMBER OF DEGREES OF WHORL
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Figure 20 .—Globigerina quinqueloba egelida, new subspecies. Growth pattern expressed as the
relationship between number of chambers and number of degrees of whorl for 10 specimens.
The measurement increase on both axes goes from the final chamber inward, not from proloculus
outward.
sent a distinct group, but specimens of this sort are only
occasionally seen and the relationship is difficult to
determine.
Comparison between G. quinqueloba egelida, new
subspecies, and G. atlantisae, new species is made
under G. atlantisae (p. 17).
Measurements.— The relationship between cham¬
ber number and test volution in ten specimens of
Globigerina quinqueloba egelida is shown in Figure
20. Chamber addition in this species is relatively con¬
sistent through ontogeny, probably most closely com¬
parable with G. atlantisae, new species (Figure 11).
Spread of points is relatively low through whorls, and
the decrease in chamber number with respect to test
volution in the periphereal whorl is negligible. The
minimum number of chambers recorded was 11 and the
maximum 16, contained in 1110°, or slightly more than
three full whorls. In the majority of specimens there
were 13 to 14 chambers, contained in 800° to 1000°;
or between two and three whorls; all specimens com¬
pleted more than two whorls. The number of chambers
in the peripheral whorl was four to five. In the pre¬
peripheral whorl the chamber number is about the
same. The number of chambers in the peripheral whorl
of G. quinqueloba egelida tends to be slightly greater
than in G. atlantisae and even slightly more so than in
G. incompta (Figures 11, 20).
Distribution. —Globigerina quinqueloba egelida,
new subspecies, occurs in most of the samples ex¬
amined. They account for less than 10 of the as¬
semblage in eleven Atlantis 77-13 and six Atlantis 77-9
samples, 15 and 20 percent in two Atlantis 77-9
samples, and 21, 22, 53, and 55 percent in five Atlantis
77-13 samples (stations 29, 4, 28, 16, and 26,
respectively).
NUMBER 4
35
Globigerina rubescens Hofker
Plate 4: figure 1
Globigerina rubescens Hofker, 1956, p. 234, pi. 35: figs. 18-
21.—Parker, 1962, p. 226, pi. 2: figs. 17,18.
Hofker (1956) remarks on the similarity of this species
to Globigerinoid.es ruber; however, no difficulty occurs
in separating the two except when small immature
specimens of G. ruber with four chambers in the final
whorl are present (see p. 38). These two forms are
separable on the basis of the juvenile specimens of G.
ruber having a much more rapid increase in chamber
size with the result that the final chamber occupies most
of the area above the previous three chambers, giving
a somewhat rectangular outline to the test, as opposed
to the almost diamond-shaped outline of Globigerina
rubescens. The aperture of G. rubescens also tends to
be more restricted than that of juvenile Globigerinoides
ruber , the wall more finely hispid, and the chambers
slightly more spherical.
Globigerina rubescens closely resembles some vari¬
ants of G. bulloides falconensis. In this case the distin¬
guishing differences are the more rapid increase of
chamber size and the less spherical shape of the cham¬
bers of G. bulloides falconensis. G. rubescens has a more
diamond-shaped outline. A few specimens of Glo-
bigerinita glutinata with relatively coarse walls are
quite similar but have more restricted apertures, in the
present populations at least.
Distribution.— Globigerina rubescens occurs in 17
assemblages from Atlantis 77-13 and one from Atlantis
77-9 collections, but never exceeds a frequency of 1
percent.
Genus Globigerinella Cushman, 1927
Globigerinella aequilateralis (Brady)
Plate 4: figures 2, 3, 4
Globigerina aequilateralis Brady, 1884, p. 605, pi. 80: figs.
18-21.
Globigerinella aequilateralis (H. B. Brady).—Phleger, Parker,
and Pierson, 1953, p. 16, pi. 2, fig. 8.
Globigerinella aequilateralis (Brady).-—Parker, 1958, p. 278,
pi. 6: figs. 5, 6.—Be, 1959, pi. 1: figs. 19, 20, 27.—Brad¬
shaw, 1959, p. 38, pi. 7: figs. 1, 2.—Cifelli, 1965, p. 22,
pi. 7: figs. 3-5.
Globigerinella siphonifera (d’Orbigny).-—Parker, 1962, p.
228, pi. 2: figs. 22-28.
Globigerinella aequilateralis is a distinctive but variable
species. Contrary to the original description, it is tro-
chospiral instead of planispiral, at least in the earlier
stages. The position of the aperture is somewhat vari¬
able but mainly is spiro-umbilical, forming a long slit
around the base of the final chamber, with a longer
extension occurring on the umbilical side. Some speci¬
mens exhibit uncoiling. Chambers vary in thickness,
and the final chamber may or may not be significantly
larger than the previous. Sutures are always depressed
and radial but the degree of depression and compact¬
ness of the test varies considerably. The wall is finely
and densely perforate and spinose.
Some immature specimens are very similar to
Globigerina bulloides and in some cases separation be¬
tween the two groups becomes almost arbitrary. Dis¬
tinction is based on the position of the aperture, which
in G. bulloides never reaches the periphery.
Distribution. — Globigerinella aequilateralis occurs
commonly in the Atlantis 1 7—13 material and rarely in
the Atlantis 77-9. Present in every sample of the form¬
er, it ranges from less than 1 to 23 percent. In the lat¬
ter, it constitutes less than 1 percent in two assemblages
and 2 percent in another.
Genus Globigerinita Bronnimann, 1951
Globigerinita glutinata (Egger)
Plate 4 : figure 5
Globigerina glutinata Egger, 1893, p. 371, pi. 13: figs. 19-21.
Globigerinita glutinata (Egger).—Phleger, Parker, and
Pierson, 1953, p. 16, pi. 2: figs. 12-15.—Be, 1959, pi. 1:
figs. 25, 26.—-Bradshaw, 1959, p. 40, pi. 7: figs. 7, 8.—
Cifelli, 1965, p. 16, pi. 3: figs. 2, 4, 5.
Parker (1962, p. 247) has reviewed the history and
discussed the complexities of this species and the genus
Globigerinita. Thus far we have no adequate criteria
for establishing morphologic limits to Globigerinita
glutinata. In particular, its relationships with Globig¬
erina bulloides falconensis of this study are obscure.
It would seem that a gradational series may exist be¬
tween the two forms although usually in assemblages
where one is abundant and of characteristic morphol¬
ogy, the other is not.
In the absence of the specifically characteristic bulla
and secondary aperture, rarely seen in North Atlantic
populations, the one seemingly distinguishing feature of
Globigerinita glutinata is the wall surface. In its typical
form, the wall surface appears smooth, white, and
shiny. Yet, if the wall surface is treated as an invariant
36
character, the species limits become narrowly defined
and exclude many specimens with otherwise identical
morphologic characters. Moreover, wall surface cannot
always be unequivocally interpreted, at least under the
binocular microscope. The surface is covered by nu¬
merous closely, irregularly spaced, short spinose
projections. These projections are small but vary in
size from specimen to specimen and in some cases they
coalesce. The size of these projections often decreases
on later chambers, sometimes not being present on the
final chamber or apertural bulla.
It is, of course, possible that the ultrastructure of
G. glutinata eventually may prove unique. Under the
binocular microscope, however, close inspection shows
that the size, density, and regularity of spacing of the
spinose projections and their relationship to the pores
seems to determine the surface appearance. Where a
high density of small spinose projections of uniform
height and spacing occurs, the apparently smooth,
shiny wall of the typical G. glutinata results. Increase
in size and irregularity in the height and spacing of
the projections results in the wall looking spinose, as in
Globigerina bulloides falconensis. A translucent, glassy
appearing wall results when the projections and pores
are widely spaced or absent. This glassy wall is similar
in appearance to that of Hastigerina pelagica. In the
present material those Globigerinita glutinata with the
most glassy wall mainly have the chamber arrangement
of adult Globigerinoides trilobus trilobus, with three
fairly compactly arranged chambers in the peripheral
whorl, a relatively large final chamber and a slit-like
extraumbilical or peripheral aperture.
In view of the apparently variant character of the
wall surface, we here interpret Globigerinita quite
broadly and include a varied suite of specimens in
Globigerinita glutinata. Included in the group re¬
ferred to Globigerinita glutinata are (1) those speci¬
mens with a compact chamber arrangement with three
to four rapidly enlarging chambers in the peripheral
whorl, mainly fairly smooth-surfaced and shiny, though
having small spinose projections and usually with a
reduced to slit-like extraumbilical to peripheral aper¬
ture with a phialine lip; (2) glassy-walled forms, with
relatively few, widely spaced small spinose projections,
four chambers in the peripheral whorl which are less
compactly arranged and less rapidly enlarging than the
above, with the final chamber only slightly if at all
larger than the penultimate, and with the aperture
centrally located in the umbilicus, but still reduced and
SMITHSONIAN CONTRIBUTIONS TO PALEOBIOLOGY
with a phialine lip; (3) specimens with some but not
all of the above characters which appear to grade into
Globigerina bulloides falconensis but generally with the
aperture more reduced or extraumbilical and with a
phialine lip and a wall that is smoother and more
shiny than that of characteristic G. bulloides falconen¬
sis. Separation from G. bulloides falconensis has been
arbitrary in some cases. No secondary apertures and
only one bulla were seen on the specimens from the
Atlantis II traverses. Occasionally, unusually glassy¬
appearing juveniles of Globigerinoides ruber and espe¬
cially G. trilobus, with its more-reduced aperture,
superficially resemble Globigerinita glutinata, but usu¬
ally can be distinguished on such features as plan of
growth and differences in the wall texture.
Distribution. — Globigerinita glutinata is present in
all of the samples of the Atlantis 77-13 traverse, but
usually in relatively low frequencies. Its maximum is 9
percent at station 19. It reaches 5 percent or more in
only six other samples. This species is much more
abundant in the Atlantis 77-9 samples, being present
at nine of the eleven stations and representing approxi¬
mately 10 percent of the assemblage at four stations
and 36 percent at another.
Globigerinita humilis (Brady)
Plate 5: figure 1
Truncatulina humilis Brady, 1884, p. 665, pi. 94: fig. 7.—
Banner and Blow, 1960a, p. 36, pi. 8: fig. 1.
Globigerinita humilis (Brady) .—Parker, 1962, p. 249, pi.
10: figs. 1-25.
A few specimens from the samples of the Atlantis II-9
traverse are referable to this species, not previously
recorded from the plankton, to our knowledge. They
are small (averaging approximately 0.20 mm in great¬
est diameter), with six to seven chambers in the pe¬
ripheral whorl and about 16 in the entire test, dis¬
tributed in about two and a half whorls. The wall is
finely and densely hispid. The chambers are inflated
and separated by narrow, depressed sutures, resulting
in a lobate periphery. Our specimens, however, lack
the modified, extended, final chamber which charac¬
terizes the type of the species. In other respects they
appear identical with the specimens of Globigerinita
humilis (Brady) figured by Parker (1962), except in
having a slightly more lobate periphery and somewhat
more coarsely hispid wall.
NUMBER 4
37
Genus Globigerinoides Cushman, 1927
Globigerinoides conglobatus (Brady)
Plate 5: figures 2, 3, 4, 5
Globigerina conglobata Brady, 1884, p. 603, pi. 80: figs. 1-5,
pi. 82: fig. 5.—Banner and Blow, 1960a, p. 6, pi. 4: fig. 4.
Globigerinoides conglobata (H. B. Brady).—Phleger, Parker,
and Pierson, 1953, p. 15, pi. 2: figs. 1-3.
Globigerinoides conglobata (Brady).—Parker, 1958, p. 279,
pi. 6: fig. 17.—Bradshaw, 1959, p. 40, pi. 7: figs. 5, 6.
Globigerinoides conglobatus (H. B. Brady).—Be, 1959, pi. 2:
figs. 7-12.
Globigerinoides conglobatus (Brady).—Parker, 1962, p. 229,
pi. 3: figs. 1-5.—Cifelli, 1965, p. 28, pi. 8: figs. 2, 3.
Globigerinoides sp. Bradshaw, 1959, p. 42, pi. 7: figs. 16, 17.
Juvenile specimens of this species closely resemble
Globigerina bulloides, but are distinguished by their
more coarsely hispid wall and the presence of at least
one secondary aperture, appearing when the specimens
are still relatively small. In nearly or fully developed
specimens of Globigerinoides conglobatus, two supple¬
mentary apertures are clearly visible in later chambers.
In the early stages, the primary aperture, although
similar to that of characteristic Globigerina bulloides,
tends to be slightly extraumbilical and slightly less
regular in shape. The chambers normally increase in
size slightly more rapidly than do those of G.
bulloides.
It is not unusual for immature specimens of this
species to totally represent or outnumber the mature
forms and, since marked changes occur during on¬
togeny, it is possible to assume two taxa are represented.
Some of the incompletely developed forms with thin
walls and open umbilical apertures are almost as large
as mature “typical” Globigerinoides conglobatus. It
seems probable that some individuals retain this form
throughout their ontogeny, although changing in
chamber shape and arrangement somewhat, while
others develop “typical” morphology.
The fully developed mature individual is very dis¬
tinct, with the final chamber sometimes capping the
apertural area of the previous part of the test and
with a very thick, honeycomblike wall and sutures
which, while not greatly depressed in the usual sense,
often are deeply incised between the extended edges
of the chambers. Apparently this wall structure and the
consequent incision of the sutures arises out of addi¬
tional deposition of calcite around the entire exposed
surface of the test, which causes spines to coalesce
around the pores and grow outward, eventually form¬
ing a pronounced honeycomblike structure. Some of
the spines protrude markedly further than the general
extended surface of the test, and long, discrete spines
are often prominent in the primary aperture. When
specimens are dissected, the early chambers can be seen
to have small pores on those parts which have not been
overgrown by later deposition of calcite. The large
adult chambers, however, show larger pores at the im¬
mediate chamber surface; this can be seen both on the
inner and outer surfaces of chambers lacking in sec¬
ondary shell growth and on the inner surfaces of cham¬
bers where the basic outer surface is concealed by the
later overgrowth. The sutures are simply depressed but
not slotlike where the honeycomb surface is absent.
Sutures become less depressed during the ontogeny.
Distribution. —Together, the two forms of Glo¬
bigerinoides conglobatus were found in all but two
samples from the Atlantis 77-13 traverse. Their com¬
bined abundances never exceed 5 percent of an as¬
semblage and both forms occur together in eight
samples. The mature form was found in one sample not
containing the incompletely developed, or simpler
form, but constituted less than 1 percent of the as¬
semblage. In eight other samples, the “juvenile” only
was found. It constituted less than 1 percent of the
assemblage in five of those, and in three samples it
constituted 3 percent, 4 percent, and 5 percent of the
assemblages, 5 percent being the greatest representa¬
tion of G. conglobatus found in this traverse. From the
Atlantis 11-9 assemblages, only one specimen is referred
to G. conglobatus, and that questionably.
Globigerinoides elongatus (d’Orbigny)
Globigerina elongata d’Orbigny, 1826, p. 277, list no. 4.—
Banner and Blow, 1960a, p. 12, pi. 3: fig. 10.
Globigerinoides elongatus (d’Orbigny).—Cifelli, 1965, p. 26,
pi. 9: fig. 5.
Globigerinoides elongatus closely resembles and pos¬
sibly is a variant form of G. ruber. It differs from the
latter in having a flattened and usually a relatively
small final chamber. It’s distributional pattern is
similar to, but more restricted than, that of G. ruber,
although G. elongatus occurs only in small numbers in
the Atlantis 77-13 traverse. Many G. ruber populations
are found with no G. elongatus associated.
38
SMITHSONIAN CONTRIBUTIONS TO PALEOBIOLOGY
Globigerinoides ruber (d’Orbigny)
Plate 5: figure 6
Globigerina rubra d’Orbigny, 1839a, p. 82, pi. 4: figs. 12—
14.—Banner and Blow, 1960a, p. 19, pi. 3: fig. 8.
Globigerinoides rubra (d’Orbigny).—Phleger, Parker, and
Pierson, 1953, p. 15, pi. 2: figs. 4, 7.—Parker, 1958, p. 279,
pi. 6: fig. 12.—Bradshaw, 1959, p. 42, pi. 7: figs. 12, 13.
Globigerinoides ruber (d’Orbigny).—Be, 1959, pi. 2: figs.
16, 17.—Parker, 1962, p. 230, pi. 3: figs. 11-13.—Cifelli,
1965, p. 25, pi. 8: figs. 1, 4.
Large, well developed Globigerinoides ruber show an
extreme streptospiral coil (Cifelli, 1965, p. 25). They
have three chambers in the peripheral whorl, with the
large, semicircular primary aperture of the final cham¬
ber situated symmetrically above the suture between
Figure 21.— Globigerinoides ruber. A growth series begin¬
ning with immature individuals showing most or part of four
chambers in the peripheral whorl rather than the char¬
acteristic three chambers found in adults and most immature
individuals.
the two preceding chambers. Two supplementary aper¬
tures are usually clearly visible at the base of the last
chamber. With large specimens, other supplementary
apertures in earlier chambers also are visible. Supple¬
mentary apertures develop late in the ontogeny, how¬
ever, and are seldom seen in small specimens. Also,
there is some variation in the coiling of the smaller
forms. Many individuals are identical in chamber
arrangement with the mature forms, but a gradation
exists between such forms and others that are less strep¬
tospiral and include a form with four chambers in the
peripheral whorl. In the latter form, which occurs
rather commonly in our populations, the aperture is
umbilical and this form closely resembles a Globigerina,
since supplementary apertures are rarely present at
this stage of development. The variation in coiling
and developmental stages of immature Globigerinoides
ruber are illustrated in Figure 21. G. trilobus shows
similar variation in coiling, and separation between
juveniles of the two species sometimes is difficult and,
with minute specimens, sometimes arbitrary, being
based on the tendency of G. ruber to have a larger
aperture.
Distribution. — Globigerinoides ruber is present in
every sample of the Atlantis 77-13 traverse, ranging
from 2 to 71 percent of particular assemblages.
No pattern of significant difference appears to exist
from sample to sample in the relative percentages of
mature and immature specimens of both forms. In
most assemblages, the mature forms outnumber the
immature forms and commonly the more characteristic
immature form outnumbers the other immature form.
To illustrate the exception, in the material from sta¬
tion 42 mature forms account for 7 percent of the
assemblage and immature forms of the four chamber
peripheral-whorled type also account for 7 percent of
the assemblage, while the more characteristic immature
forms represent less than 1. With the Atlantis 77-9
traverse, G. ruber was not commonly found, account¬
ing for less than 5 percent of four assemblages and
12 percent of another.
Globigerinoides trilobus trilobus (Reuss)
Plate 6: figure 1
Globigerina triloba Reuss, 1850, p. 374, pi. 47: fig. 11.
Globigerinoides sacculifera (Brady).—Parker, 1958, p. 280,
pi. 6: fig. 4 [top two specimens],—Bradshaw, 1959 [part],
p. 42, pi. 7: figs. 15, 18 [not fig. 14].
NUMBER 4
39
Figure 22.— Globigerinoides trilobus trilobus. A growth series beginning with immature indi¬
viduals showing four chambers in the peripheral whorl rather than the characteristic three
chambers found in adults and most immature individuals.
Globigerinoides sacculifer (H. B. Brady).—Be, 1959 [part],
pi. 2: figs. 13, 14 [not fig. 15].
Globigerinoides trilobus trilobus (Reuss).—Cifelli, 1965
[part], p. 26, pi. 9: figs. 1, 4 [not figs. 2, 3],
Included here is the form sacculifer which has a asc-
like final chamber. This form, however, is very poorly
developed and rare in the Atlantis II material. It was
observed in only three samples.
As discussed previously, immature stages of Globi¬
gerinoides trilobus trilobus are sometimes difficult to
separate from immature G. ruber. Small specimens of
both species vary in coiling of chambers and include
a form with four chambers in the peripheral whorl.
In the latter form the main distinction from G. ruber
is that the aperture of G. trilobus trilobus tends to be
more slit-like and restricted. Changes in coiling and
developmental stages of G. trilobus are shown in Fig¬
ure 22. This series does not, however, include the
smallest specimens of G. trilobus. These specimens go
beyond the four-chamber-peripheral-whorl stage, hav¬
ing five or even six chambers in what is the peripheral
whorl at that early stage of development. G. ruber on
the other hand, apparently does not have as large a
number of chambers in the very early whorls.
Some variation occurs among immature forms in
density of spines. Where spines are widely spaced, the
test has a smooth appearance and in a few cases closely
resembles Globigerinita glutinata.
Distribution. — Globigerinoides trilobus occurs in
most of the Atlantis II- 13 assemblages (15 out of 19)
but in low frequencies. It constitutes 1 percent or less
in 9 assemblages and reaches peaks of 8 and 9 percent
at stations 13 and 21, respectively. Only one specimen
was referred to G. trilobus from the Atlantis II-9 tra¬
verse, and that questionably.
Family GLOBORTALIIDAE Cushman, 1927
Genus Globorotalia Cushman, 1927
Globoratalia hirsuta (d’Orbigny)
Plate 6: figure 2
Rotalina hirsuta d’Orbigny, 1839b, p. 131, pi. 1: figs. 37-39.
Pulvinulina canariensis d’Orbigny.—Brady, 1884, p. 692, pi.
103: figs. 8-10.
Globorotalia hirsuta (d’Orbigny).—Phleger, Parker, and
Pierson, 1953, p. 19, pi. 4: figs. 1-7.—Be, 1959, pi. 1:
figs. 4, 8.—Bradshaw, 1959, p. 44, pi. 8: figs. 1, 2.—Par¬
ker, 1962, p. 236, pi. 5: figs. 10-15.—Cifelli, 1965, p. 19,
pi. 5: figs. 2, 3.
In the Atlantis II samples no problems were encoun¬
tered in recognition of Globorotalia hirsuta nor with its
separation from other taxa, although in other samples
we have seen, this is not always the case. This species
is similar to but easily distinguishable from Globoro¬
talia punctulata. As in the latter, there are four cham¬
bers in the peripheral whorl. Also, there is a similarity
between the two species in the shape and relative in¬
crease in size of chambers. The chambers, however,
are less inflated in G. hirsuta and the periphery is
consequently more acute. There is some lobulation of
the periphery in G. hirsuta and a distinct keel bounds
each of the chambers on most specimens, although on
rare occasions it is not present on all chambers of a
40
given specimen. The keel often forms an even, un¬
broken slope with the wall of the chamber and it is
not always readily apparent, especially on the spiral
side. The wall is quite thick, a fact apparent particu¬
larly from seeing the pores passing through the wall.
Perhaps the most distinctive features of Globorotalia
hirsuta are the convexity of the spiral side and the
papillate surface of the test. There is considerable
range in the convexity among the specimens from the
Atlantis II traverses but in no instance was a spiral
side found to be flat. The umbilical side is normally
flat but among the larger specimens it is sometimes
concave. Papillae vary in size and density among speci¬
mens. Fine papillae sometimes continue onto the keel.
The sutures in G. hirsuta are flush to depressed on
the spiral side and depressed on the umbilical side.
On the spiral side the sutures sometimes appear lim-
bate, owing to the juxtaposition of the keels of the
chambers with previous chambers. On some specimens
chambers are added at such an angle to one another
that the edge of a previous chamber is much higher
than the beginning of the next. A calcite thickening
often occurs on the spiral side, obscuring the earlier
chambers and making the early chambers, those inside
the peripheral whorl, resemble an unbonal boss.
In a population of 50 individuals from Atlantis II-9
station 327, specimens range in maximum diameters
from 0.22 mm up to 0.89 mm, with a mean of 0.43.
Distribution: — Globorotalia hirsuta is well repre¬
sented from the Atlantis II~9 traverse but very sparsely
from the Atlantis 77-13. It occurs in abundances of
less than 1 to 29 percent in nine of the eleven stations
of the former and less than 1 percent in five of the
nineteen stations of the latter.
Globorotalia menardii (d’Orbigny)
Rotalia menardii d’Orbigny, 1826, p. 273, no. 26, Modeles,
no. 10.
Pulvinulina menardii (d’Orbigny).—Brady, 1884, p. 690, pi.
103: figs. 1, 2.
Globorotalia menardii (d’Orbigny).—-Phleger, Parker, and
Pierson, 1953, p. 19, pi. 3: figs. 1, 2, 4, 5.—-Be, 1959, pi. 1:
figs. 1—3.—Bradshaw, 1959, p. 44, pi. 8: figs. 3, 4.—Cifelli,
1965, p. 19, pi. 6: figs. 3, 4.
This species occurs sparingly in the Atlantis II traverses.
The maximum size of specimens is 0.90 mm but the
average is between 0.40 and 0.50 mm. There are about
15 chambers in the test and the chambers increase
SMITHSONIAN CONTRIBUTIONS TO PALEOBIOLOGY
rapidly in size in the peripheral whorl. The test mainly
is thin, almost translucent, and has a rather thin, uni¬
formly developed keel which extends around the cham¬
bers as they develop, forming limbate sutures and
increasing the lobulation of the test in its later part.
Distribution. — Globorotalia menardii was found
in frequencies of less than 1 to 3 percent at 13 of the 19
Atlantis 77-13 stations, being less than 1 percent in all
but two. It was not recorded from the Atlantis 77-9
traverse.
Globorotalia punctulata (d’Orbigny)
Plate 6: figure 3
Globigerina punctulata d’Orbigny, 1826, p. 277, Modeles, no.
8.—Fomasini, 1898, p. 210, fig. 5.
Pulvinulina crassa (d’Orbigny).—Brady, 1884, p. 694, pi.
103: figs. 11, 12.
Globorotalia punctulata (d’Orbigny).—Phleger, Parker, and
Pierson, 1953, p. 20, pi. 4: figs. 8—12.—Parker, 1958, p.
281.—Be, 1959, p. 83, pi. 1: figs. 9-11.—Cifelli, 1965, p.
18, pi. 4: fig. 4, pi. 5: fig. 1.
Globorotalia crassaformis (Galloway and Wissler).—Parker,
1962, p. 235, pi. 4: figs. 17, 18, 20,21.
The possible affinities of this species with Globigerina
inflata have been discussed (see p. 28). In Globorotalia
punctulata, the periphery is distinctly angular, al¬
though not particularly acute, except in the smaller
specimens. The aperture is umbilical-extraumbilical,
narrow, and with a distinct lip.
There are four chambers in the peripheral whorl
and, in plan view, the periphery is subrounded to sub-
rectangular. Sutures are narrow and slightly depressed.
The umbilicus is relatively shallow and narrow, but
distinct, and increases in dimensions with maturity of
specimens. For the most part a keel is not developed in
this species; however, on the larger specimens there is
sometimes a trace of an apparently imperforate rim on
the later chambers.
Papillae or spinose projections of variable size and
spacing cover both sides of the test. On the average,
these projections are larger than the spinose projec¬
tions seen on Globigerina inflata and smaller than those
papillae on Globorotalia hirsuta. Papillae are best de¬
veloped on the larger specimens.
Distribution. — Globorotalia punctulata was found
in frequencies of 2 percent or less at eight of the nine¬
teen Atlantis 77-13 stations. It was not found in sam¬
ples from the Atlantis 11-9 traverse.
NUMBER 4
41
Globorotalia scitula (Brady)
Plate 6: figure 4
Pulvinulina scitula Brady, 1882, p. 716.—Banner and Blow,
1960a, p. 27, pi. 5: fig. 5.
Pulvinulina patagonica d’Orbigny sp.—Brady, 1884, p. 693,
pi. 103: fig. 7.
Globorotalia scitula (H. B. Brady).—Phleger, Parker, and
Pierson, 1953, p. 21, pi. 4: figs. 13, 14.
Globorotalia scitula (Brady).—Parker, 1958, p. 281; 1962,
p. 238, pi. 6: figs. 2, 3.—Bradshaw, 1959, p. 44, pi. 8: figs.
5, 6.
This species is meagerly represented in the two Atlantis
II traverses of this study. The few specimens present
are small (average maximum diameter 0.23 mm),
compressed, but slightly convex on both sides with a
rather sharp although not carinate periphery. Approxi¬
mately 15 chambers occupy the test in between two
and three whorls, with five to six chambers in the pe¬
ripheral whorl. The wall surface is mainly smooth and
shiny with very small pores, but some specimens have
irregularly distributed, small, short spinose projections
marking the surface. The spinose projections appear
more concentrated at the outer edges of chambers. The
sutures are narrow to slightly limbate and are slightly
depressed on both sides of the test. They are curved,
becoming strongly so between later chambers. The
aperture is umbilical-extraumbilical with a small sim¬
ple lip in the umbilical area. No difficulty occurred in
identifying Globorotalia scitula in the Atlantis II sam¬
ples. In other material, however, G. scitula sometimes
presents taxonomic problems.
Distribution. — Globorotalia scitula does not occur
in the Atlantis 77-13 assemblages. It accounts for from
less than 1 to 2 percent of six of the 11 Atlantis 77-9
assemblages.
Globorotalia truncatulinoides (d’Orbigny)
Rotalina truncatulinoides d’Orbigny, 1839b, p. 132, pi. 2:
figs. 25-27.
Pulvinulina michelineana d’Orbigny.—Brady, 1884, p. 694,
pi. 104: figs. 1,2.
Globorotalia truncatulinoides (d’Orbigny).—Phleger, Parker,
and Pierson, 1953, p. 22, pi. 4: figs. 17, 18.—Parker, 1958,
p. 281; 1962, p. 239, pi. 6: fig. 7.—Be, 1959, pi. 1: figs.
5-7.—Bradshaw, 1959, p. 44, pi. 8: figs. 7, 8.-—Cifelli,
1965, p. 20, text-fig. 3, pi. 6: figs. 1, 2.
Although not abuntantly represented, Globorotalia
truncatulinoides from the the Atlantis II traverses in¬
cludes well-developed forms with a mean maximum
diameter of 0.48 mm (based on the specimens from
three samples). This compares well with the maximum
size of specimens from Pacific bottom sediments re¬
ported by Parker (1962, p. 239). The total number of
chambers cannot be ascertained from the present speci¬
mens because papillae cover the wall and obscure the
early chambers. There are five chambers in the peri¬
pheral whorl and this number is constant. A well-devel¬
oped but not particularly thick keel bounds the periph¬
ery of the test. The wall is of moderate thickness and
is covered with papillae on both the spiral and umbili¬
cal sides. The papillae are smaller and less dense on
the chambers of the peripheral whorl on the spiral side
as a rule, and considerable variation may exist in their
denseness among chambers of a single specimen and
among specimens of a population. Papillae occur on
small, immature specimens as well as fully developed
ones. They continue onto the keel. The umbilicus is
relatively narrow, although very deep, especially on
the large subconical specimens. Apertural lips are poor¬
ly developed or absent. In plan view, the peripheral
outline is subrounded to subangular overall but usually
with a pronounced projection formed by the final
chamber. The sutures are slightly curved, narrow, and
slightly depressed on the umbilical side. On the spiral
side they are slightly curved, very slightly depressed,
and tend to be slightly limbate, reflecting the presence
of the keel; the keel also causes the spiral suture to be
limbate. Over 90 percent of the specimens examined
are left coiled.
Distribution. — Globorotalia truncatulinoides is not
abundant but is fairly well represented in some of the
Atlantis 11-9 samples, but is rare in the Atlantis 77-13
assemblages. In the former, it ranges in frequency from
less than 1 to 11 percent in eight of the eleven samples.
In the latter traverse, G. truncatulinoides is present but
accounts for less than 1 percent of three assemblages.
Genus Hastigerina Thomson, 1876
Hastigerina pelagica (d’Orbigny)
Nonionina pelagica d’Orbigny, 1839c, p. 27, pi. 3: figs. 13,
14.
Hastigerina murrayi Thomson, 1876, p. 534, pis. 22, 23.
Hastigerina pelagica (d’Orbigny).—Brady, 1884, p. 613, pi.
83; figs. 1-18.—Parker, 1958, p. 280, pi. 6: fig. 15; 1962,
p. 228.—Be, 1959, pi. 2; figs. 21, 22.—Bradshaw, 1959,
p. 47, pi. 8: figs. 14, 15.—Banner and Blow, 1960b, p. 20,
fig. 1.—Cifelli, 1965, p. 23, pi. 7: figs. 1, 2-
42
SMITHSONIAN CONTRIBUTIONS TO PALEOBIOLOGY
This distinctive species, which is rare but present in
most of the Atlantis II samples, has a very fragile test.
Its thin and transparent wall is smooth and glassy but
finely and densely perforate with a few long, promi¬
nent spines, which may pass through the wall from one
whorl to another. It is planispiral to slightly trocho-
spiral, with a broad, low but open aperture crossing the
base of the final chamber from one side of the test
to the other. The sutures are narrow and deeply in¬
cised, resulting in a very lobate test outline. The cham¬
bers increase rapidly in size, with five usually present in
the peripheral whorl. Hastigerina pelagica is similar to
Globigerinella aequilateralis but the nature of the wall
and the more planispiral coiling easily distinguish it.
Distribution.— Specimens of Hastigerina pelagica
were found in small numbers in ten samples (2 per¬
cent or less of assemblages) from the Atlantis 77-13
traverse and four samples from the Atlantis 77-
9 traverse.
Genus Orbulina d’Orbigny, 1839
Orbulina universa d’Orbigny
Plate 6: figure 5
Orbulina universa d’Orbigny, 1839a, p. 3, pi. 1: fig. 1.—
Brady, 1884, p. 608, pi. 81: figs. 8-26, pi. 82: figs. 1-3.—
Phleger, Parker, and Pierson, 1953, p. 17, pi. 2: fig. 8.—
Parker, 1958, p. 280, pi. 6: fig. 13.—Be, 1959, pi. 2: fig-
18.—Bradshaw, 1959, p. 49, pi. 8: figs. 17, 18.—Cifelli,
1965, p. 17, pi. 3: figs. 6,7.
Orbulina universa is present in most Atlantis 77-13
samples, but in very small numbers. Some specimens
contain internal chambers. Most of the internal cham¬
ber arrangements found are rather incomplete, but
rare forms were found which look similar to Globig-
erina bulloides as well as the juvenile form of Globig-
erinoides conglobatus.
Four specimens included here appear identical with
Orbulina suturalis. They have a minute initial coiled
end with poorly defined sutures and well-developed
pores at the junction of the initial end with the final
large bulbous chamber (Plate 6: figure 5).
Distribution. — Orbulina universa was found in
very small numbers at 18 of the 19 Atlantis 77-13 sta¬
tions. It is not recorded from the smaller samples of
the Atlantis 77-9 traverse.
Family DISCORBIDAE Ehrenberg, 1838
Genus Tret omphalus Moebius, 1880
Tretomphalus atlanticus Cushman
Tretomphalus atlanticus Cushman, 1934, p. 86, pi. 11: fig.
3, pi. 12: fig. 7.—Phleger, Parker and Pierson, 1953, p. 43,
pi. 9: figs. 30, 31.
Most of the small number of Tretomphalus atlanticus
collected appear to be juvenile forms, with relatively
few chambers and a deep and wide slot-shaped opening
almost bisecting the concave ventral surface. No speci¬
mens with “float chambers” were found. The small
specimens begin with a round proloculus followed by
approximately a whorl of four to six chambers which
are subrounded to elongate (in the direction of coil¬
ing) and have sutures at first radial then curved and
oblique. In the large specimens the elongate chambers
are succeeded by rather irregular whorls of chambers
of variable shape and number.
Distribution. —This species occurs solely in sam¬
ple 286 from the Atlantis 77-9 traverse. In this small
assemblage, Tretomphalus atlanticus accounts for 20
percent of the specimens.
Family PLANORBULINIDAE Schwager, 1877
Genus Planorbulina d’Orbigny, 1826
Planorbulina mediterranensis d’Orbigny
Planorbulina mediterranensis d’Orbigny, 1826, p. 280, no. 2,
pi. 14: figs. 4—6, bis; Modeles, no. 79.—Phleger, Parker
and Pierson, 1953, p. 50, pi. 11, figs. 20, 21.
These few individuals consist of large numbers of
irregularly shaped, but tending toward hemispherical
to hemielliptical, chambers arranged in bent, irregular
subplanispiral coils. On some specimens, the early
chambers are regularly arranged, as in Cibicides. The
surface is coarsely punctate. The dorsal surface is
quite rough, whereas the ventral surface is smooth,
allowing early whorls to be seen more clearly. The
aperture forms a slit at the base of the final chamber;
the apertures of many earlier chambers can be seen
also, because of the irregular nature of the addition of
chambers.
Distribution. —Members of this genus constitute
30 percent of the small assemblage from station 286
of the Atlantis 77-9 traverse.
NUMBER 4
43
Literature Cited
Banner, F. T. and W. H. Blow
1960a. Some Primary Types of Species Belonging to the
Superfamily Globigerinaceae. Contributions of
the Cushman Foundation for Foraminiferal Re¬
search, 11(1): 1-14, plates 1-8.
1960b. The Taxonomy, Morphology, and Affinities of the
Genera Included in the Subfamily Hastigerininae.
Micropaleontology, 6(1): 19—31, figures 1—11.
Be, A. W. H.
1959. Ecology of Recent Planktonic Foraminifera, Part 1:
Areal Distribution in the Western North Atlantic.
Micropaleontology, 5(1): 77-100, plates 1, 2.
1960a. Some Observations on Arctic Planktonic Forami¬
nifera. Contributions from the Cushman Founda¬
tion for Foraminiferal Research, 11(2) : 64-68.
1960b. Ecology of Recent Planktonic Foraminifera, Part 2:
Bathymetric and Seasonal Distributions in the
Sargasso Sea off Bermuda. Micropaleontology
6(4):373-392.
1968. Shell Porosity of Recent Planktonic Foraminafera
as a Climatic Index. Science, 161:881-884.
Be, A. W. H., and W. H. Hamlin
1967. Ecology of Recent Planktonic Foraminifera, Part 3:
Distribution in the North Atlantic During the
Summer of 1962. Micropaleontology, 13(1): 87—
106.
Berger, W. H.
1968. Planktonic Foraminifera: Selective Solution and
Paleoclimatic Interpretation. Deep-Sea Research,
15:31-43.
Blow, W. H.
1959. Age, Correlation and Bistratigraphy of the Upper
Tocuyo (San Lorenzo) and Pozon Formations,
Eastern Falcon, Venezuela. Bulletin of American
Paleontology, 39(178):67—251, plates 6-19.
Boltovskoy, E.
1968. Hidrologia de las Aguas Superficiales en la Parte
Occidental del Atlantico Sur. Revista Museo
Argentino de Ciencia Natural “Bernardino Riva-
davia.” Hidrobiologia, 2(6) : 199-224.
Bradshaw, J. S.
1959. Ecology of Living Planktonic Foraminifera in the
North and Equatorial Pacific. Contributions of
the Cushman Foundation for Foraminiferal Re¬
search, 10(2):25-64, plates 6-8.
Brady, H. B.
1882. Report on the Foraminifera. In Tizard and
Murray, Exploration of the Faroe Channel, During
the Summer of 1880 in H. M.’s Hired Ship Knight
Errant, with Subsidiary Reports. Proceedings of
the Royal Society of Edinburgh (1880-1882),
11(111):708—717.
1884. Report on the Foraminifera Dredged by H.M.S.
Challenger, During the Years 1873—1876. Zoology
(in two volumes) 9:1-814, plates 1—115.
Cifelli, R.
1961. Globigerina incompta, a New Species of Pelagic
Foraminifera from the North Atlantic. Contribu¬
tions of the Cushman Foundation for Foraminiferal
Research, 12(3):83-86, plate 4.
1962. Some Dynamic Aspects of the Distribution of
Planktonic Foraminifera in the Western North
Atlantic. Journal of Marine Research 20(3):
201-213.
1965. Planktonic Foraminifera from the Western North
Atlantic. Smithsonian Miscellaneous Collections,
148(4): 1-36, plates 1-9.
1967. Distributional Analysis of North Atlantic Foramini¬
fera Collected in 1961 During Cruises 17 and 21 of
the R/V Chain. Contributions of the Cushman
Foundation for Foraminiferal Research. 18(3):
118-127.
Cifelli, R., and K. N. Sachs, Jr.
1966. Abundance Relationships of Planktonic Foramini¬
fera and Radiolaria. Deep-Sea Research, 13:751-
753.
Cifelli, R., and R. K. Smith
1969. Problems in the Distribution of North Atlantic
Foraminifera and their Relationships to Water
Masses. Bronnimann and Renz, editors, Proceedings
of the First International Conference on Planktonic
Microfossils, Geneva.
Cushman, J. A.
1934. Notes on the Genus Tretomphalus, with Descrip¬
tions of Some New Species and a New Genus,
Pyropilus. Contributions from the Cushman Lab¬
oratory for Foraminiferal Research, 10(4) : 79-101,
plates 11-13.
Earland, A.
1934 (1935). Foraminifera, Part III: The Falklands
Islands Sector of the Antarctic (excluding South
Georgia). Discovery Reports, Cambridge, 10:1-
208, plates 1-10.
Egger, J. G.
1893. Foraminiferen aus Meeresgrundproben, Gelothet
von 1874 bis 1876 von S. M. Schiff Gazelle.
Koeniglich Bayerische Akademieder Wissenschaf-
ten. Mathematisch-Physikalische Classe. Akhand-
lungen, 1895, 18(2) : 195-458, plates 1-21.
Fornasini, G.
1898 (1899). Le Globigerine Fossili d’ltalia. Palaeon-
tographia ltalica, Pisa, 4:203—216, Plates 1—21.
Hofker, J.
1956. Foraminifera Dentata. Foraminifera of Santa Cruz
and Thatch-Island, Virginia-Archipelago, West
Indies. Copenhagen Universitet Zoologiske Mu¬
seum, Skrifter, 15:1-237, plates 1-35.
Kennett, J. P.
1966. Foraminiferal Evidence of a Shallow Calcium
Carbonate Solution Boundary, Ross Sea, Antarctica.
Science, 153(3732): 191-193.
44
SMITHSONIAN CONTRIBUTIONS TO PALEOBIOLOGY
Mann, G. R.
1967. The Termination of the Gulf Stream and the Begin¬
ning of the North Atlantic Current. Deep-Sea
Research, 14:337-359.
Natrella, M. G.
1963. Experimental Statistics. National Bureau of Stand¬
ards Handbook 91, Washington, D.C., 504 pages.
Orbigny, A. d’
1826. Tabuleau Methodique de la Classe des Cephalo-
podes. Annales des Sciences Naturelles, series 1,
7:96—314, plates 10-17.
1839a. Foraminiferes. In de la Sagra, Historie Physique,
Politique et Naturelle de l’ile de Cuba: 1-224,
[plates published separately]. Paris: Bertrand.
1839b. Foraminiferes des lies Canaries. In Barker-Webb
and Berthelot, Histoire Naturelle des lies Canaries,
2(2, Zoologie): 119-146, plates 1-3. Paris:
Bethune.
1839c. Voyage dans I’Amerique Meridionale Foramini¬
feres. 5(5): 1-86, plates 1-9. Strasbourg: Betrand.
Parker, F. L.
1958. Eastern Mediterranean Foraminifera. Reports of
the Swedish Deep-Sea Expedition, 8(4): 219-283,
plates 1—6.
1962. Planktonic Foraminiferal Species in Pacific Sedi¬
ments. Micropaleontology, 8(2): 219-254, plates
1 - 10 .
Phleger, F. B, F. L. Parker, and J. F. Pierson
1953. North Atlantic Foraminifera. Reports of the
Swedish Deep-Sea Expedition, 7(1) :3—122, plates
1 - 12 .
Reuss, A. E.
1850. Neues Foraminiferen aus den Schichten des oster-
reischischen Tertiarbeckens. Koeniglich Akademie
der Wissenschaften, Wien. Mathematische-Natur-
wissenschaftliche Klasse. Denkschriften, 1:365-390,
plates 46-51.
Rhumbler, L.
1901. Nordische Plankton-Foraminiferen. Nordisches
Plankton, 2(14): 1—32, figures 1-33.
1909. Die Foraminifem (Thalomorphen) der Plankton-
Expedition. Ergebnisse der Plankton-Expedition
der Humbolt-Schiftung, 3:7-331, plates 1-39.
Sachs, K. N., Jr.
1965. Removal of Ash from Plankton Samples Concen¬
trated by Ignition. Deep-Sea Research, 12:697.
Sachs, K. N., Jr., R. Cifelli, and V. T. Bowen
1964. Ignition to Concentrate Shelled Organisms in
Plankton Samples. Deep-Sea Research, 11:621—
622.
Smith, R. K.
1967. Ignition and Filter Methods of Concentrating
Shelled Organisms. Journal of Paleontology,
41(5): 1288-1291.
Stommel, H.
1965. The Gulf Stream, 202 pages. Berkeley: Univer¬
sity of California Press.
Sverdrup, H. V., M. W. Johnson, and R. H. Fleming
1942. The Oceans, 1087 pages. New York: Prentice-
Hall, Inc.
Thomson, W.
1876. In Murray, Preliminary Reports to Professor Wy-
ville Thomson, F.R.S., Director of the Civilian Sci¬
entific Staff, on Work Done on Board the Chal¬
lenger. Proceedings of the Royal Society of London,
24:534, plates 22, 23.
Todd, R., and P. Bronnimann
1957. Recent Foraminifera and Thecamoebina from the
Eastern Gulf of Paria. Cushman Foundation for
Foraminiferal Research, Special Publication Num¬
ber 3: 1-43, plates 1-12.
Uchio, T.
1960. Planktonic Foraminifera of the Antarctic Ocean.
Special Publication Seto Marine Biological Labora¬
tory. Biological Results of the Japanese Antarctic
Research Expedition, 11:3-10, plate 1.
Worthington, L. V.
1959. The 18° Water in the Sargasso Sea. Deep-Sea
Research, 5:297-305.
1962. Evidence for a two Gyre Circulation System in the
North Atlantic. Deep-Sea Research, 9:51—67
Plate 1.—1, Globigerina atlantisae, new species, holotype: a, spiral view; b, side view; c, umbilical view; X 140. 2, Globigerina
atlantisae, new species, paratype: a, spiral view; b, side view; c, umbilical view; X 135. 3, Globigerina atlantisae, new species,
paratype: a, spiral view; b, side view; c, umbilical view; X 135. 4, Globigerina bulloides falconensis: a, spiral view; b, side view;
c, umbilical view; X 95. 5, Globigerina bulloides bulloides: a, spiral view; b, umbilical view; X 80. 6, Globigerina bulloides
bulloides: a, spiral view; b, umbilical view; X 60.
46
SMITHSONIAN CONTRIBUTIONS TO PALEOBIOLOGY
Plate 2.—1, Globigerina dutertrei: a, spiral view; b, side view; c, umbilical view; X 65. 2, Globigerina dutertrei (juvenile) :
a, spiral view; b , side view; c, umbilical view; X 130. 3, Globigerina incompta: a, spiral view; b, side view; c, umbilical view;
X 95. 4, Globigerina inflata: a, spiral view; b, side view; c, umbilical view; X 75. 5, Globigerina inflata: a, spiral view; b, side
view; c, umbilical view; X 70.
Plate 3.—1, Globigerina megastoma: a, spiral view; b, side view; c, umbilical view; X 80. 2, Globigerina aff. G. pachyderma
(juvenile) : a, spiral view; b, side view; c, umbilical view; X 80. 3, Globigerina aff. G. pachyderma: a, spiral view; b, side view;
c, umbilical view; X 80. 4, Globigerina quinqueloba egelida, new subspecies, holotype: a, spiral view; b, side view; c, umbilical
view; X 140. 5, Globigerina quinqueloba egelida, new subspecies, paratype: a, spiral view; b, side view; c, umbilical view; X 135.
6, Globigerina quinqueloba egelida, new subspecies, paratype: a, spiral view; b, umbilical view; X 145. 7, Globigerina quinque¬
loba egelida, new subspecies, paratype: a, umbilical view; b, spiral view; X 180.
48
SMITHSONIAN CONTRIBUTIONS TO PALEOBIOLOGY
Plate 4.—1, Globigerina rubescens: a, spiral view; b, side view; c, umbilical view; X 145. 2, Globigerinella aequilateralis: a,
spiral view; b, side view; c, umbilical view; X 95. 3, Globigerinella aequilateralis: a, spiral view; b, side view; c, umbilical view;
X 40. 4, Globigerinella aequilateralis: a, spiral view; b, side view; c, umbilical view; X 100. 5, Globigerinita glutinata: a, spiral
view; b, side view; c, umbilical view; X 145.
Plate 5.—1, Globigerinita humilis: a, spiral view; b, side view; c, umbilical view; X 150. 2, Globigerinoides conglobatus (juve¬
nile): a, spiral view; b, umbilical view; X 125. 3, Globigerinoides conglobatus (juvenile) : a, spiral view; b, umbilical view;
X 80. 4, Globigerinoides conglobatus: a, spiral view; b, umbilical view; X 75. 5, Globigerinoides conglobatus: a, spiral view;
b, umbilical view; X 30. 6, Globigerinoides ruber: a, umbilical view; b, side view; c, spiral view; X 70.
Plate 6.—1, Globigerinoides trilobus trilobus: a, spiral view; b, side view; c, umbilical view; X 95. 2, Globorotalia hirsuta:
a, spiral view; b, side view; c, umbilical view; X 70. 3, Globorotalia punctulata: a, spiral view; b, side view; c, umbilical view;
X 65. 4, Globorotalia scitula: a, spiral view; b, side view; c, umbilical view; X 130. 5, Orbulina universa: X 105.
Index
[Names of new species in italics, page numbers of principal accounts in boldface.]
aequilateralis, Globigerinella, 5, 7 (fig.), 8, 9, 11, 15, 17, 19,
35,42,48 (pi.)
atlanticus, Tretomphalus, 7 (fig.), 13, 42
atlantisae , Globigerina, 7 (fig.), 15, 17 (fig.), 18 (fig.),
34, 45 (pi.)
bulloides, Globigerina, 6 (fig.), 8, 9, 10, 13, 14, 15, 18, 19,
20, 35, 37,42
bulloides bulloides, Globigerina, 7 (fig.), 15, 18, 19 (fig.),
20,27,45 (pi.)
bulloides falconensis, Globigerina, 7 (fig.), 19, 20, 35, 36,
45 (pi.)
canariensis, Pulvinulina, 39
Cibicides, 42
conglobata, Globigerina, 37
Globigerinoides, 37
conglobatus, Globigerinoides, 7 (fig.), 19, 37, 42, 49 (pi.)
crassa, Pulvinulina, 40
crassaformis, Globorotalia, 40
dubia, Globigerina, 21
dutertrei, Globigerina, 7 (fig.) 15, 21, 22, 23 (fig.), 24 (fig.),
25, 26, 28, 30, 32, 46 (pi.)
Globoquadrina, 21
eggeri, Globigerina, 21, 26
elongata, Globigerina, 37
elongatus, Globigerinoides, 7 (fig.), 37
falconensis, Globigerina, 20
Globigerina, 5, 9, 10 (fig.), 11, 12, 13, 14, 15, 17, 38
atlantisae, 7 (fig.), 15, 17 (fig.), 18 (fig.), 34, 45 (pi.)
bulloides, 6 (fig.), 8, 9, 10, 13, 14, 15, 18, 19, 20, 35,
37,42
bulloides bulloides, 7 (fig.), 15, 18, 19 (fig.), 20, 27, 45
(pi-)
bulloides falconensis, 7 (fig.), 19, 20, 35, 36, 45 (pi.)
conglobata, 37
dubia, 21
dutertrei, 7 (fig.), 15, 21, 22, 23 (fig.), 24 (fig.), 25, 26,
28,30,32, 46 (pi.)
eggeri, 21, 26
elongata, 37
falconensis, 20
incompta, 5, 6 (fig.), 7 (fig.), 8 (fig.), 9, 10, 11, 12,
13, 14, 15, 21, 22, 23 (fig.), 24, 25, 26, 27 (fig.), 28,
30, 32, 34, 46 (pi.)
inflata, 5, 6 (fig.), 7 (fig.), 8, 9, 10 (fig.), 13, 14, 15, 27,
28, 29 (fig.), 40, 46 (pi.)
megastoma, 7 (fig.), 29, 47 (pi.)
pachyderma, 21, 26, 27, 30, 31, 33
aff. G. pachyderma, 7 (fig.), 15, 21, 22, 23 (fig.), 24, 25,
26, 28, 29, 30, 31 (fig.), 32, 47 (pi.)
pachyderma incompta, 26, 29
punctulata, 40
Globigerina—Continued
quinqueloba, 32, 33
aff. G. quinqueloba, 32, 33
cf. quinqueloba, 32, 33
quinqueloba egelida, 5, 6 (fig.), 7 (fig.), 8 (fig.), 9,
10, 11, 13, 15, 17 (fig.), 18,27, 32, 33, 34 (fig.), 47 (pi.)
radians, 17
rubescens, 7 (fig.), 20, 35,48 (pi.)
rubra, 38
triloba, 38
Globigerinella, 35
aequilateralis, 5, 7 (fig.), 8, 9, 11, 15, 17, 19, 35, 42,
48 (pi.)
siphonifera, 35
Globigerinita, 35, 36
glutinata, 7 (fig.), 14, 15, 20, 35, 36, 39, 48 (pi.)
humilis, 7 (fig.), 36, 49 (pi.)
iota, 17
Globigerinoides, 5, 37
conglobata, 37
conglobatus, 7 (fig.), 19, 37, 42, 49 (pi.)
elongatus, 7 (fig.), 37
ruber, 5, 6 (fig.), 7 (fig.), 8 (fig.), 9, 10, 11, 13, 15,
20, 35, 36,37, 38 (fig.), 39, 49 (pi),
rubra, 38
sacculifer, 39
sacculifera, 38
trilobus, 20, 36, 38, 39
trilobus trilobus, 7 (fig.), 20, 36, 38, 39 (fig.), 50 (pi.)
Globoquadrina, 21
dutertrei, 21
Globorotalia, 39
crassaformis, 40
hirsuta, 5, 7 (fig.), 13, 14, 15, 39, 40, 50 (pi.)
inflata, 28
menardii, 7 (fig.), 40
punctulata, 7 (fig.), 28, 29 (fig.), 39, 40, 50 (pi.)
scitula, 7 (fig.), 41, 50 (pi.)
truncatulinoides, 5, 7 (fig.), 13, 14,41
glutinata, Globigerinita, 7 (fig.), 4, 15, 20, 35, 36, 39, 48 (pi.)
Hastigerina, 41
murrayi, 41
pelagica, 7 (fig.), 36, 41, 42
hirsuta, Globorotalia, 5, ? (fig.), 13, 14, 15, 39, 40, 50 (pi.)
Rotalina, 39
humilis, Globigerinita, 7 (fig.), 36,49 (pi.)
Truncatulina, 36
incompta, Globigerina, 5, 6 (fig.), 7 (fig.), 8 (fig.), 9, 10,
11, 12, 13, 14, 15, 21, 22, 23 (fig.), 24, 25, 26, 27
(fig.), 28, 30, 32, 34,46 (pi.)
51
52
INDEX
inflata, Globigerina, 5, 6 (fig.), 7 (fig.), 8, 9, 10 (fig.),
13, 14, 15, 27, 28, 29 (fig.), 40, 46 (pi.)
Globorotalia, 28
iota, Globigerinita, 17
mediterranensis, Planorbulina, 7 (fig-), 13, 42
megastoma, Globigerina, 7 (fig.), 29,47 (pi.)
menardii, Globorotalia, 7 (fig.), 40
Pulvinulina, 40
Rotalina, 40
michelineana, Pulvinulina, 41
murrayi, Hastigerina, 41
Nonionina, 41
pelagica, 41
Orbulina, 42
suturalis, 42
universa, 7 (fig.), 14, 42, 50 (pi.)
pachyderma, Globigerina, 21, 26, 27, 30, 31, 33
aff. G. pachyderma, Globigerina, 7 (fig.), 15, 21, 22, 23 (fig.),
24, 25, 26, 28, 29, 30, 31 (fig.), 32, 47 (pi.)
pachyderma incompta, Globigerina, 26, 29
patagonica, Pulvinulina, 41
pelagica, Hastigerina, 7 (fig.), 36, 41, 42
Nonionina, 41
Planorbulina, 42
mediterranensis, ? (fig.), 13,42
Pulleniatina, 28
Pulvinulina, 39, 40, 41
canariensis, 39
crassa, 40
menardii, 40
michelineana, 41
patagonica, 41
scitula, 41
punctulata, Globigerina, 40
Globorotalia, 7 (fig.), 28, 29 (fig.), 39, 40, 50 (pi.)
quinqueloba, Globigerina, 32, 33
aff. G. quinqueloba, Globigerina, 32, 33
cf. quinqueloba, Globigerina, 32, 33
quinqueloba egelida, Globigerina, 5, 6 (fig.), 7 (fig-), 8
(fig.), 9, 10, 11, 13, 15, 17 (fig.), 18, 27, 32, 33, 34
(fig.), 47 (pi.)
radians, Globigerina, 17
Rotalina, 39, 40, 41
hirsuta, 39
menardii, 40
truncatulinoides, 41
ruber, Globigerinoides, 5, 6 (fig.), 7 (fig.), 8 (fig.), 9, 10,
11, 13, 15, 20, 35, 36, 37, 38 (fig.), 39, 49 (pi.)
rubescens, Globigerina, 7 (fig.), 20, 35, 48 (pi.)
rubra, Globigerina, 38
Globigerinoides, 38
sacculifer, Globigerinoides, 39
sacculifera, Globigerinoides, 38
scitula, Globorotalia, 7 (fig.), 41, 50 (pi.)
Pulvinulina, 41
siphonifera, Globigerinella, 35
suturalis, Orbulina, 42
Tretomphalus, 42
atlanticus, 7 (fig.), 13, 42
triloba, Globigerina, 38
trilobus, Globigerinoides, 20, 36, 38, 39
trilobus trilobus, Globigerinoides, 7 (fig.), 20, 36, 38, 39
(fig.), 50 (pi.)
Truncatulina, 36
humilis, 36
truncatulinoides, Globorotalia, 5, 7 (fig.), 13, 14, 41
Rotalina, 41
universa, Orbulina, 7 (fig.), 14, 42, 50 (pi.)
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