ZONE OF AMALTHEUS MARGARITATUS. 



101 



On the south side of Portree harbour thin-bedded, bhiish, micaceous sandstones, 

 forming the Marf/arifatus-heds, are exposed, and yielded the following shells, which were 

 chiefly collected in Raasay : 



Fossils from the Marffaritatus-zone, Island of Raasay. 



Amaltheus raargaritatus, Montf. 

 Belemnites paxillosus, Schloth. 



— breviformis, Volts. 



— longissimus, Mill. 

 Tectaria Gaudryana, (VOrb. 

 Chemnitzia Blainvillei, Miinst. 

 Pecten sequivalvis. Sow. 



— liasinus, Nyst. 



— strionates, Tate. 

 Avicula noyemcostse, Brown. 



— cygnipes, Young and Bird. 

 Lima Hermanni, Voltz. 



Limea acuticosta, Miinst. 

 Pleuromya ovata, Rum. 

 Pholadomya ambigua. Sow. 

 Mytilus scalprum, iSW. 



Leda graphica, Tate. 

 Ostrea cymbium, Lamk. 

 Plicatula spinosa, Sow. 

 Cypricardia cucullata, Goldf. 

 Macrodon intermedius, Simp. 

 Arcomya arcacea, Seebach. 

 Ceromya liassica, Tate. 

 Lingula Voltzii, David. 

 Rbyiicbonella acuta, Sow. 



— subconica, David. 



— tetraedra, Sow. 

 Terebratula punctata, Sow. 

 Spiriferina Miinsteri, David. 



— rostrata, Schloth. 

 Eryma propinqua, Blake. 

 Pentacrinus amaltbei, Qriensf. 



Foreif/n Correlations. — The Marc/aritatus and Bpinatus zones are widely distributed 

 in North Germany, and, although these two horizons may sometimes be separated, they 

 often are so closely united that they must be studied together. Von Strombeck'^ has 

 made careful studies of the Anialtheenschichten in different regions of that country, 

 and found them in the Helmsted, Schoppensted, and Harzburg Jura, containing Amal. 

 marfjaritatus, Amal. spinatiis, Cryptcenia expansa. Turbo cyclostoma, Gresslya ventricosa, 

 Astarte striato-sulcata, Leda elliptica, Inoceramus suhstriatus. Ewald" found the same 

 species near Halberstadt ; H. Romer, near Hildesheim ; Bornemann, near Gottingen ; 

 Credner,' in Hilsmulde, near Stroit ; and Schlonbach,* near Liebenburg and near 

 Salzgitter, with a similar assemblage of MoUusca; so that the upper zones of the 

 Middle Lias are well represented in the north. In South Germany the Margaritatus- 

 beds are found in Swabia, and were long ago described by Professor Quenstedt in his 

 ' Flotzgebirge Wiirttembergs,' and afterwards by Dr. Oppel in ' Der mittlere Lias 

 Schwabens,' whilst in his ' Juraformation ' he divided the Marffaritatus-h&A.?> into a 

 lower and upper zone. 



In the lower zone Amal. maryaritatus is often associated with Lytoceras fimbriatum, 



1 'Zeitschrift d. D. geol. Gesellschaft,' vol. v, Jahrg., 1853. 



3 Ibid., 1859. 



» ' Jabrbucb f. Min.,' 1860. 



* ' Zeitscbrift d. D. geol. Gesellschaft,' vol. xv, Jabrg., 1863. 



