Ch. XXXI.] UPPER MIOCENE VOLCANOES. 675 



Among the fossil shells common to Madeira and Porto Santo, large 

 cones, strombs, and cowries.are conspicuous among the univalves, and 

 Cardium, Spondylus, and LitJiodomus among the lamellibranchiate 

 bivalves. Among the JSchinoderms the large Clypeaster, C. alius, an 

 extinct European Miocene fossil, is seen. 



The largest list of fossils has been published by M. Karl Meyer, in 

 Hartung's " Madeira ; " but in the collection made by myself, and in a 

 still larger one formed by Mr. J. Yate Johnson, several remarkable 

 forms not in Meyer's list occur, as, for example, Pholadomya, and a 

 large Terebra. Mr. Johnson also found a fine specimen of Nautilus 

 (Atruria) zigzag, a well-known Falunian fossil of Europe ; and in 

 the same volcanic tuff of Baixo, the Echinoderm Brissus Scillce, a 

 living Mediterranean species, found fossil in the Miocene strata of 

 Malta. M. Meyer identifies one-third of the Madeira shells with 

 known European Miocene (or Falunian) forms. The huge Strombus 

 of San Vicente and Porto Santo, S. Italicus, is an extinct shell of the 

 Subapennine or Older Pliocene formations. 



The mollusca already obtained from various localities of Madeira 

 and Porto Santo are not less than one hundred in number, and, accord- 

 ing to Dr. S. P. Woodward, rather more than a third are of species 

 still living, but many of these are not now inhabitants of the neighbor- 

 ing sea. 



It has been remarked (p. 213) that in the Older Pliocene and 

 Upper Miocene deposits of Europe, many forms occur of a more 

 southern aspect than those now inhabiting the nearest sea. In like 

 manner the fossil corals, or Zoantharia, six in number, which I ob- 

 tained from Madeira, of the genera Astrcea, Sarcinula, Hydnophora, 

 &c, were pronounced by Mr. Lonsdale to be forms foreign to the ad- 

 jacent coasts, and to agree with those of more tropical latitudes and 

 parts of the Eed Sea. So the Miocene shells of the Madeiras seem to 

 belong to the fauna of a sea warmer than that now separating Madeira 

 from the nearest 'part of the African coast. We learn, indeed, from 

 the observations made in 1859, by the Rev. R. T. Lowe, that more 

 than one-half, or fifty-three in ninety, of the marine mollusks collected 

 by him from the sandy beach of Mogador are common British species, 

 although Mogador is 18-J- degrees south of the nearest shores of Eng- 

 land. The living shells of Madeira and Porto Santo are in like man- 

 ner those of a temperate climate, although in great part differing spe- 

 cifically from those of Mogador. * 



Grand Canary. — In the Canaries, especially in the Grand Canary, 

 the same marine Upper Miocene formation is found. Stratified tuffs, 

 with intercalated conglomerates and lavas, are there seen in nearly 

 horizontal layers in sea-cliffs about 300 feet high, near Las Palmas. 

 M. Hartung and I were unable to find marine shells in these tuffs at a 

 greater elevation than 400 feet above the sea ; but as the deposit to 



* Linnasan Proceedings ; Zoology, 1860. 



