These are the factors that determine the zoogeographical distribution of marine organisms, the limits of the territory occupied by different species. KEY TO THE SUPERSPECIFIC GROUPS OF THE FAMILY PYRAMIDELLIDAE REPRESENTED IN THE PLIOcene FAUNA I.
KEY TO THE SUPERSPECIFIC GROUPS OF THE FAMILY PYRAMIDELLIDAE REPRESENTED IN THE PLIOCENE FAUNA OF
Snails with an absent or obsolete radula; operculum ovate paucispiral, with apex anteriorly, a filiform arcuate ridge on proximal side, inner margin notched in harmony with column bracts when prominent; leg short, moderately pointed behind, with a small operculigerous lobe above and sometimes with a small tentacular appendage on each side, slightly auricled or wavy in front; mantle slightly channeled on right upper margin; one branch; margin subcylindrical, elongated; head with two flattened subtriangular or oblong tentacles, connate, grooved or auricled in larger forms, funicles with ciliate surface; eyes behind or between base of tentacles; mouth opening below the antennae. The shell is wrinkled, with a wrinkled axis; outer lip often lirate internally; in larger forms the opening is vaguely channeled in front; The larval shell is sinistral, the adult is right, the first is often set at an angle to the axis of the adult or
NO. 2 PYRAMIDELLID MOLLUSKS BARTSCH 7
8 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I25
KEY TO THE PYRAMIDELLIDAE WITH TRIPLICATE COLUMELLA
NO. 2 PYRAMIDELLID MOLLUSKS — BARTSCH 9
KEY TO THE SUBGENERA OF LONGCHAEUS
10 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I25 and less oblique than the othef two ; outer lip reinforced at irregular
NO. 2 PYRAMIDELLID MOLLUSKS — BARTSCH II
KEY TO THE PYRAMIDELLIDAE WITH BIPLICATE COLUMELLA
KEY TO THE SPECIES OF LOCKLINIA Summit of the whorls without spiral cord
It has lost the nucleus and about 3 of the postnuclear whorls; the 9 remaining measurements: Length 6.8 mm. Aperture oval, parietal wall covered with a thin callus; columella with two folds, the posterior one of which is at the insertion of the columella and is much stronger than the anterior one, which is also much more oblique; the outer lip bears three spiral lamellae on the inner side. perfect specimen and comes from the Pliocene deposits of North St. It has 9 postnuclear whorls and measures: Length 4.8 mm., diameter i.i mm. 2571) is another specimen from the same source showing the inner lamination of the outer lip.
KEY TO THE SUBGENERA OF EULIMELLA
Parietal wall covered by a moderately thick callus; columella with two folds, of which the posterior part, which is a.
14 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I25 Subgenus Cossmannica Dall and Bartsch
KEY TO THE SUBGENERA OF ORINELLA
NO. 2 PYRAMIDELLID MOLLUSKS — BARTSCH I5
The junction of the axial ribs and the spiral cords forms strong tubercles, with those on the first cord at the top slightly less strong than the others. Of these ribs ii of equal strength are present on the last seven-eighths of the last whorl in the type and 6 others.
KEY TO THE SUBGENERA OF TURBONILLA Axial ribs and incised intercostal spaces extending over the base to
KEY TO THE SPECIES OF THE SUBGENUS CHEMNITZIA
NO. 2 PYRAMIDELLID MOLLUSKS — BARTSCII I9
These ribs have the same strength from the top of the rolls to their termination at the periphery. Nucleus consists of about 2.5 strongly rounded whorls forming a small raised apex, the axis of which is at right angles to that of the postnuclear apex, in the former of which the latter are slightly sunken.
NO. 2 PYRAMIDELLID MOLLUSKS — BARTSCH 21
22 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I25 rounded and provided with strong, decidedly protractively slanting
NO. 2 PYRAMIDELLID MOLLUSKS BARTSCH 23
The remaining whorls are flattened and crossed by slender, slightly undulating, decidedly protractively inclined axial ribs, 13 of which are present on the last whorl of the type. 561628 contains another copy from the same source and two more are in the collection of the A.N.S.P.
KEY TO THE SPECIES OF MORMULA
Pyramidellids with axial ribs and deeply incised spiral lines or grooves; also irregularly disposed varices on the outer surface, which usually mark internal lirations on the outer lip, or internal lirations only on the outer lip.
28 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I25 protractively slanting and are of the same strength from the summit
NO, 2 PYRAMIDELLID MOLLUSKS — BARTSCH 29 aperture is subquadrate ; the columella is short, moderately stout, re-
30 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 125
The suture is slightly narrowed and wavy at the top of the axial ribs. Of these ribs, 16 are present on the second to fifth whorls; 17 at six o'clock; 18 on the seventh and 20 on the remaining rings.
NO. 2 PYRAMIDELLID MOLLUSKS — BARTSCH 33
34 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I25
NO. 2 PYRAMIDELLID MOLLUSKS — BARTSCH 35
36 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I25 The rounded whorls and spiral sculpture easily distinguish this
KEY TO THE SPECIES OF PYRGISCUS
38 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I25 Incised spiral lines not 6
NO. 2 PYRAMIDELLID MOLLUSKS — BARTSCH 39
561632 contains seven additional specimens from the same source and seven more, seven additional specimens from the same source and seven more. Strongly rounded whorls and strong axial ribs will distinguish this species from the other five spirally perforated forms. 561634 contains two additional specimens from the same source, two of which are in the collection of A.N.S.P.
561636 contains II additional specimens from the same source, and another 13 are in II additional specimens from the same source, and another 13 are in the collection of the A.N.S.P.
42 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I25
The core consists of 2.5 strongly rounded vortices, forming a compressed helicoid spiral, the axis of which is perpendicular to the axis of the postnuclear vortices, of which about one quarter is immersed in the first. Those that remain are flattened and crossed by moderately strong, vertical, axial ribs, of which 14 are present on the first and second of the remaining whorls, 16 on the third and fourth, 17 on the fifth, 22 on the sixth, while beyond these ribs become progressively thinner and more closely spaced and show aging characteristics. Of these ribs, 17 are present on the first to third remaining whorls, 20 on the fifth and 22 on the last.
Base rather long, hemispherical, marked by the weak continuation of the slightly extending axial ribs.
NO. 2 PYRAMIDELLID MOLLUSKS — BARTSCH 45
46 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I25 right angles to that of the postnuclear spire, in the first whorl of
NO. 2 PYRAMIDELLID MOLLUSKS — BARTSCH 47
48 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I25 tractively slanting axial ribs, of which in the cotype having the nuclear
NO. 2 PYRAMIDELLID MOLLUSKS — BARTSCH 49
50 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I25 elevated helicoid spire whose axis is at right angles to that of the
NO. 2 PYRAMIDELLID MOLLUSKS — BARTSCH 5
52 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I25 PYRGISCUS HEBEAE, new species
The new specimen has the nucleus and 6.1 postnuclear whorls and measures: Length 2.2 mm, diameter 0.7 mm.
HYBRIDIZATION AMONG MOLLUSKS
54 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL, I25
NO. 2 PYRAMIDELLID MOLLUSKS — BARTSCH 55
56 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL, I25 gradually contaminated with the fluxed elements from the overflows
2 THE PYRAMIDELIDA MOLLUSCS — BARTSCH 57 hybridization has caused a great flourishing of individuals, and hybridization has caused a great flourishing of individuals, and on the west coast it has also caused the said pyramidals to extend their range into the neighboring faunal areas in which they are fixed to region are limited. The sculpture consists of axial ribs and a mixture of strong incised spiral grooves and fine spiral lines in the intercostal spaces. Nuclear whorls are usually turbonilloid; they form a helical apex, the axis of which is located at right angles to the axis of the postnuclear whorls.
The intercostal spaces of the vortices show an enormous range of differentiation in spiral sculpture in the com-.
58 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 12$
These ribs pass over the periphery of the last whorl on the base, where they become decidedly reduced. Base pit rounded, marked as indicated above by the faint continuations of the axial ribs. I am pleased to name this species balchi in recognition of the great amount of help FrancisN.
The nuclear vortices are deeply obliquely immersed in the first post nuclear spin, from which only the oblique edge of the last whorl protrudes.
60 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I25 separate them, which cross the spiral grooves and extend up on the
B. Adams
KEY TO THE SPECIES OF CHRYSALLIDA Axial ribs stronger than the spiral cords
These spiral cords are evenly spaced, the first on top and the last. The suture is deeply impressed and wavy due to the strong nodules at the top of the whorls. The base is slightly rounded and marked with five spiral cords, successively slightly smaller than the one below the margin towards the tip of the columella.
The connection of the axial ribs and the spiral cords produce very strong oval tubercles, the axis of which corresponds to the spiral cords.
64 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I25 wonderful fauna of the Caloosahatchie deposits focused attention
NO. 2 PYRAMIDELLID MOLLUSKS — BARTSCH 65 which makes the lateral outline of the spire appear almost as a straight
The junction of the axial ribs and spiral cords forms strong elongated tubercles, the long axis of which corresponds to the spiral cords. The junction of the axial ribs and the spiral cords forms strong, oval tubercles, the long axis of which corresponds to the spiral cords. The suture is only slightly narrowed and wavy due to the very strong outgrowths at the top of the whorls.
The postnuclear whorls are slightly rounded and marked by moderately strong, vertical axial ribs of equal strength from the apex to the fifth spiral cord.
70 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I25 CHRYSALLIDA WOODRINGI, new species
NO. 2 PYRAMIDELLID MOLLUSKS — BARTSCH 7I
Aperture elongate-oval, cast at junction of basal lip and columella; columella. The suture is deeply channeled and undulated by the tubercles at the apex of the whorls. The connection of the axial ribs and spiral cords forms strong, round tubercles, while the closed spaces between them are round pits.
The postnuclear whorls are characterized by strong, retractively oblique axial ribs, which extend undiminished from the apex to the periphery of the whorls.
78 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I25 This is also the case of the space that separates the fourth cord from
NO. 2 PYRAMIDELLID MOLLUSKS — BARTSCH 79
80 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 12$
KEY TO THE SPECIES OF FARGOA
The base is well rounded and marked by five spiral strands, which become progressively weaker from the periphery to the umbilical region. I am pleased to name this species for Archie Pogue Cales, the discoverer of the Pliocene deposit of North St. The base is marked with five spiral cords, which become successively smaller from the periphery towards the umbilical cord.
561669 contains another copy from the same source, and another copy is in the collection of the A.N.S.P.
KEY TO THE SPECIES OF EULIMASTOMA
NO. 2 PYRAMIDELLID MOLLUSKS — BARTSCH 83
KEY TO THE SUBGENERA OF ODOSTOMIA
84 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL, I25 Subgenus Evalea A. Adams
KEY TO THE SPECIES OF THE SUBGENUS EVALEA Base umbilicated
The apex of the successive whorls falls a short distance below the peripheral angulations, making the suture appear deeply canalized. The apex of the successive whorls is adjacent to this cord, leaving the suture less conspicuous than in Odostomia {Evalea) pomeroyi. The entire surface of the spire and base is marked by many finely incised spiral lines.
The aperture is egg-shaped; the columella is slender and slightly curved and has a faint inner fold slightly below the insertion; the parietal wall is covered with a weak callus;.
86 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I25 The lack of a deeply chaneled suture will readily distinguish this
KEY TO THE SPECIES OF THE SUBGENUS ODOSTOMIA
NO. 2 PYRAMIDELLID MOLLUSKS BARTSCH 87
561726 contains six additional specimens from the same source, and five more are in the collection of the A.N.S.P. The nucleus is deeply embedded in the first postnuclear whorl above which only the obliquely inclined edge protrudes. The thinner outline and less open umbilicus will easily distinguish this species from Odostomiajohnsoni (p. 87).
The much stronger shape will easily distinguish this species from Odostomia stephensoni (below), which also has an angular periphery.
90 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I25 ODOSTOMIA (ODOSTOMIA) SCHWENGELAE, new species
The core lies deeply obliquely submerged in the first postnuclear whorl, above which only the rounded, tilted edge of the last evolution emerges. The core is deeply submerged obliquely in the first postnuclear whorl, above which only a small part of the rounded edge of the final development extends. The core is deeply submerged obliquely in the first postnuclear whorl, above which only the rather thick edge of the last coil protrudes.
The nuclear whorls are deeply obliquely immersed in the first postnuclear whorl, above which only the rounded, oblique edge of the last whorl projects.
NO. 2 PYRAMIDELLID MOLLUSKS BARTSCH 93 twisted by the internal fold a little below its insertion ; the parietal
94 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL, I25 nuclear whorls are high between the sutures and almost flattened
The core is deeply submerged obliquely in the first postnuclear whorl, above which only the rounded, tilted edge protrudes.
INDEX
98 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL, I25
NO. 2 INDEX 99
3,Lockliniapliocena,type;4, Ugartealocklini,type;s, Orinella (Sulcorinella) locklini, type;6, Peristichia martschi, type; 7, Locklinia ornata, type; 8, Locklinia fargot, type;. 5, a, b, Turbonilla (Chemnitsia) atlas, cotyper; 6, med Turbon (Chemnitsia) antaeiisi, type; 7, Turbonilla (Chemnitsia) cerberusi, type; 8, a, b, Mormula woodringi, type;. 1, EulimVstoma harbisonae, type; 2, Fargoa calesi, type; 3, Miralda {Miraldella) gordonae, type; 4, Fargoaarchcri, type; 5, Eulimostoma olssoni, type; 6, Chrysallida pilsbryi, nitrogen; 7, Chrysallida mcgintyi, type; 8, Chrysallida leai, nitrogen; 9, Chrysallida holmesi, type;.
