56 EXCURSIONS IN MADEIRA 



leaving any vestige of a crater. Here I had the gratification of 

 seeing the Manta for the first time, a new species of eagle, connect- 

 ing the divisions haliatus and pandion of Savigni/, and which ought, 

 perhaps, to form an intermediate one, under the name of limncetus : 

 first, because the same natural character which has separated the 

 hali(Etus from the 'pandion, separates the limneetus from both, for 

 its nails instead of being grooved underneath as in the former, or 

 round, as in the latter, are perfectly flat ; and secondly, from an 

 equal difference in its habits, for although evidently an aquatic 

 eagle from its half-feathered tarsi, it neither frequents the sea hke 

 the haliatus, nor rivers, like the pandmi, but haunts the jiools and 

 other stagnant waters of the mountains, and feeds on water-insects 

 and worms, amphibious reptiles, grylli, and small birds, but not on 

 fish''. Returning leisurely, and in broad day, I could not but be 

 struck with the numerous basaltic dikes which advanced from the 

 heights, and projected into the valleys and ravines, like buttresses 

 or bare walls. It was every where evident that these dikes had 

 intersected beds of tufa, which had been decomposed and washed 

 away by the rains and torrents, aad the frequent occurrence ap- 

 peared to me to have contributed considerably to the formation of 

 the small valleys and ravines, and to their fertility, being thus 

 naturally covered with what is considered the best soil in the 

 island. It is also evident, that these vast, irregular deposits of tufa 

 cannot have resulted from decomposition, but must have been 

 poured out as an irruption, before the basalt. The prisms met 

 vA\h in different parts of the road from the Coural to the Poul,' are 

 of various sizes, of a more compact basalt, and, generally speaking, 



'■ Back and head, brown ; tail, light brown, with transverse bands of the darker brown 

 of the back ; throat and belly yellowish, with transverse waves of dark brown ; inside 

 of the wings whitish, with similar waves ; tail square, with ten long pen-feathers ; 

 tarsi, yellow ; length, one foot nine inches ; envergure four feet one inch. The gastric 

 glands descend into the stomach in four longitudinal bands. 



