ZONE OF AMALTHEUS MARGARITATUS. 



101 



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

 forming the Margaritatus-h%^^, are exposed, and yielded the following shells, which were 

 chiefly collected in Raasay : 



Fossils from the Margaritatus-zone , Island of Raasay. 



Amaltheus margaritatus, Montf. 

 Beleranites paxillosus, Schloth. 



— breviformis, Volts. 



— longissimus, Mill. 

 Tectaria Gaudryana, (TOrb. 

 Chemnitzia Blainvillei, Mimst. 

 Pecten sequivalvis. Sow. 



— liasinus, Nyst. 



— strionates, Tate. 

 Avicula novemcostae, Brown. 



— cygnipes, Young and Bird. 

 Lima Hermanni, Voltz. 



Limea acuticosta, 3Iiinsf. 

 Pleuromya ovata, Hum. 

 Pholadomya ambigua, Sow. 

 Mytilus scalprum, Soiv. 



Leda graphica, Tate. 

 Ostrea cymbium, Lamk. 

 Plicatula spinosa, Sow. 

 Cypricardia cucullata, Goldf. 

 Macrodon intermedius, Simp. 

 Arcomya arcacea, S-eebach. 

 Ceromya liassica, Tate. 

 Lingula Voltzii, David. 

 RhynchoneHa acuta, Sow. 



— subconica, David. 



— tetraedra. Sow. 

 Terebratula punctata, Sow. 

 Spiriferina Miinsteri, David. 



— rostrata, Schloth. 

 Eryma propinqua, Blake. 

 Pentacrinus araalthei, Querist. 



Foreign Correlations. — The Margaritatus and Spinatus zones are widely distributed 

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

 often are so closely united tha! they must be studied together. Von Strombeck^ has 

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

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

 margaritatus, Amal. spinatus, Crypteenia expansa. Turbo cyclostoma, Gresslga ventricosa, 

 Astarte striata- sulcata, Leda elliptlca, Inoceramus substriatus. Ewald" found the same 

 species near Ilalberstadt ; II. Romcr, near Hildesheim ; Bornemann, near Gottingen ; 

 Credner,'' in Ililsmulde, near Stroit ; and Schlonbach,^ near Liebenburg and near 

 Salzgitter, with a similar assemblage of Moihisca; 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 Wiirttembcrgs,' and afterwards by Dr. Oppel in ' Der raittlere Lias 

 Schwabens,' whilst in his ' Juraforraation ' he divided the Margaritatus-h^^^ into a 

 lower and upper zone. 



In the lower zone Amal. margaritatus is often associated with Lgtoceras fimbriatum 



1 ' Zeitsclirift d. D. geol. Gesellschaft,' vol. v, Jahrg., 18;33. 



2 Ibid., 1859. 



3 'Jabrbuch f. Min.,' 18G0. 



4 'Zeitschrift d. D. geol. Gesellschaft,' vol. xv, Jahrg., 1863. 



