UTRECHT MICROPALEONTOLOGICAL BUllETINS

IV.I. INTRODUCTION
Wherever possible, the conodont specimens were arranged into their
supposed natural (i.e. multi-element) species. The reconstruction of such
assemblages was based on the combination of some or all of the following
indications:
- The similarity of the stratigraphic range of the elements.
- Comparable relative frequencies of the elements per sample.
- Similarities in colour and/or mineral composition.
- The similarity of one or more morphologic features of different elements.
- The elemental composition of already described "natural species".
The "natural species" were named according to the rules of the LC.Z.N.
Code. Also the suggestions of the Pander Society Document 3 were
followed.
The names of the separate elements within the multi-element species were
derived from comparable form genera or species. The terminology of the
morphologic features has been adopted from Lindstrom (1964, p. 11).
All material is stored in the collections of the Micropaleontology Department
of the Geological Institute of the State University of Utrecht, colI. nrs.
T191-198 and CHl141-1306.
Genus Coelocerodontus ETHINGTON, 1959
Type species: Coelocerodontus trigonius ETHINGTON, 1959.
Definition: "Hollow horn-shaped cones. I"ateral walls are thin and enclose a
central cavity which extends to the tip of the tooth. Edges of the tooth are
keeled. Species are identified on the basis of the shape of the cross section."
Coelocerodontus bicostatus n. sp.
(Pl.1, figs. la, b)
Derivatio nominis: bicostatus, Lat. = carrying two costae.
Holotype: see PI. 1, figs. la, b, cat. nr. Tl91-13.