36 LAKE SUPERIOR. 



on four or five great divisions, though with some diiFerenees. Thus the 

 waders, or those birds having the tarsus and a space above it naked, are 

 put in one group by some, and by others made into two. The arrangement 

 of the water birds now most generally admitted is : Palmipedes : with the 

 feet united, except in one group, (the grebes, &c.) This division, I incline 

 to think, is made on an insufl&cient consideration of tbeir true affinities. 

 Grallatores : with three toes before, and one behind. The gallinaceous 

 bird,'? form a very natural group, having the upper jaw arched, and feet like 

 those of the grallatores, but with short and curved claws. The climbers have 

 two toes before and two behind, of which one may generally be moved in 

 either direction. Sometimes there is only a trace of this arrangement, in a 

 closer union of two of the toes with each other than with the rest. The 

 passerines have curved claws, or sometimes the hind-claw is straight ; three 

 toes before and one behind. Some make three groups of them, bring- 

 ing together those with flattened bills, (Inseetivora ;) those with conical 

 bills, (Granivora,) and those with the upper mandible much stronger than 

 the lower, (Omnivora.) Some again separate from these the swallows, 

 pigeons, &c. 



" The toes in all birds have the same number of joints. The hind toe 

 always consists of a single joint, the inner toe of two, the middle of three, 

 and the outer of four. This arrangement is important in distinguishing the 

 fossil tracks of birds from those of other animals, it being peculiar to them. 



" In examining birds within the egg, I have recently found some charac- 

 ters to be less important than has been supposed. Thus the foot of the 

 embryo robin is webbed, like that of the adult duck ; so also in the sparrow, 

 swallow, summer-yellow-bird, and others, in all of which the adult has divided 

 toes. The bill also is crooked and the point of the upper mandible projecting, 

 as in the adult form of birds of prey. These latter, then, it would seem, 

 should be brought down from the high place assigned to them on account 

 of their voracious and rapacious habits, as if these would entitle an animal 

 to a higher rank. For the resemblance of an adult animal to the embryo 

 of another species, indicates a lower rank in the former.* Probably the true 

 classification of birds would include various series, each embracing represen- 

 tatives of all the various types now admitted as distinct." 



Mr. Ballcnden, of the Hudson's Bay Co., to whom the Professor 

 had letters, paid him a visit to-day, and showed the most obliging 



* For further details see Prof. Agassiz's Lectures on Comparative Embryology, 

 delivered at the Lowell Institute, January, 1819 ; published in the Daily Evening Truth 

 eller, and afterwards in a pamphlet form by the same publishers. 



