102 Dr. T. Wrio:ht on Fossil Echinoderms 



'& 



and surveyed and mapped by the Earl Ducie*. Through his 

 lordship's kindness, we have been enabled to study a complete 

 suite of Maltese rock specimens, together with an extensive col- 

 lection of the fossils obtained from them, whilst resident in the 

 island ; and it is but just that we should state, at the outset of 

 these remarks, that whatever is valuable in this memoir relating 

 to the stratigraphical distribution of the Urchins and other 

 fossils in these beds, is entirely due to the Earl Ducie, who has 

 most liberally given us all the information he noted on the spot, 

 relative to the range and distribution of the species. It is to 

 be distinctly understood, however, that neither the measurement 

 of the beds, nor the limitation of the range of the fossils in 

 them, are given as absolute truths, but rather as the nearest 

 approximation thereto which the present state of our knowledge 

 permits. 



The Maltese islands comprise Malta, Gozo, and Cumino. 

 Malta is seventeen miles in length by seven in breadth ; Gozo 

 is nine in length by five in breadth ; and Cumino about two 

 in length by one in breadth. The direction of their long axis 

 is S.E. and N.W., which, with the channels, is about twenty-nine 

 miles in length. All the rocks are sedimentary and marine, having 

 a slight inclination from N.E. to E.N.E. ; their direction corre- 

 sponds with that of the Apennines, and with the intermediate 

 line observed in Sicily from the Val di Noto to Polizzi. Nume- 

 rous faults traverse the N.W. half of Malta and the S.E. of Gozo, 

 which have much disturbed the beds, caused the depressions now 

 forming the north and south channels between Cumino and Malta 

 and Cumino and Gozo, and left the islet of Cumino an isolated 

 fragment of the uppermost beds, which attests the former con- 

 tinuity of the land, before these islands were fractured by subter- 

 ranean and denuded by aqueous agency. '^ The mineral deposits,^' 

 says Capt. Spratt, "composing this group, have a thickness of 

 800 feet visible above the sea ; they lie nearly horizontal, and are 

 conformable, although there is a great diversity of mineral cha- 

 racter and condition in the series. None of the deposits are 

 wholly destitute of organic remains ; but, on the contrary, they 

 generally contain them in tolerable abundance, and in a good 

 state of preservation." The strata may be divided into five groups, 

 each of which contains fossils that are special to it, very few of 

 the species being common to the whole series. These, in a 

 descending order, are, 1st, the coralline limestone ; 2nd, the yellow 

 sand', 3rd, the clay; 4th, the calcareous sandstone] 5th, the 

 hard cherty limestone. 



* The Earl Ducie kindly presented a copy of this map to Mr. Good- 

 enough, book- and map-seller, Strado Reale, Malta, by whom it is now 

 being published. 



