ORTHOCERATID^. 127 
Denkschr. d. k. k. Akad. d. Wissensch. Band xxx. p. 60, 
Taf. xxxvi. f. 8. 
1877. Orihoceras poUtum, Barrande, Syst. Sil. de la Bolieme, toI. ii. 
Texte T. p. 1325, pi. cccclxxxviii. cases x. and xi. 
1882. OrtJioceras poUtum, Mojsisovics, Die Cephalopoden der Mediter- 
ranen Triasproxinz, in Abliandl. der k. k. geologiscli. Beiclisanst. 
p. 293, Taf. xcii. fi. 13, 14, Taf. xciii. IF. 7, 8. 
Sp. Char. Shell straight. Section circular. Bate of tapering 1 in 
10, as estimated from a specimen figured by Mojsisoxics. Body- 
chamber constricted near the aperture. Septa very widely sepa- 
rated, their distance exceeding the shell-diameter. Siphuncle central 
according to Mojsisovics, but Klipstein describes it in a very young 
and imperfect individual (the type specimen) as a little removed from 
the central position. Surface showing fine transverse strife. 
Remarhs. Mojsisovics observes (loc. cit.) that this species belongs 
to a series with widely separated septa, in which 0. dubiiim^ v. 
Hauer, is contained, but that it is distinguished from the latter 
mainly by the difierent character of its shell-ornaments, and also by 
its rather more pointed apex. 
These beds contain a remarkable fauna in which there is a com- 
mingling of Palaeozoic and Mesozoic types, which serve in a measure 
to bridge over the gap between these two great divisions of the 
rocks. The following are some of the more important species of 
the MoUusca ; — Orihoceras eJer/ans, ^Miinst.; 0. poUtum, Klipstein ; 
Ammonites Aon, Miinst.: A. Eryx, Miinst.; Bellerophon nautilinvs, 
Miinst.; Monodonia Cassiana, AVissm.; Macroclieilus ohovatum, M.; 
Phasianella Bronni, Wissm.; Murchisonia BJumi, Miinst.; Nucida 
lineata, Goldf.; N. striydata, Goldf.; GervWia anyusta, Miinst.; 
Cassianella yryphcmta, Miinst.; Cardita crenata, Goldf.; Koninclcina 
Leonardi, Wissm., &c. This list is taken from Credner’s ‘ Elemcnte 
der Geologic,’ 6th edition, p. 581. The most complete account of 
the fauna of the Alpine Trias is contained in a series of papers by 
Dr. G. C. Laube in the ‘ Denkschriften der k. Akad. der Wissen- 
schaften,’ Vienna, 1864-1869. 
Horizon. Trias ; Cassianer Schichten (St. Cassian Beds). 
Locality. St. Cassian, South Tyrol. 
Represented in the Collection by two very small specimens. 
Orthoceras elegans^ Munster. 
1834. Orthocera elegans, Mtinster, in Leonhard & Bronn’s Neues Jahrb. 
p. 11. 
1841. Orthocera elegans, Miinster, Beitr. zur Geognosie und Petre- 
factenkunde des siidostlichen Tirol's, p. 125, Taf. xiv. f. 2. 
