146 Transactions of the American Institute. 



birds had an advantage in the earliest periods of time. With regard 

 to this poetical idea of the power of flight, a creature having wings 

 being always a favorite object for comparisons, allegories, &c. I 

 must say in defense of the class of creatures with which I wish now 

 to compare the birds, that they are also ihentioned among the fowls 

 of the air as flying above the earth ; and the record of their existence 

 refers not to birds exclusively, but has direct reference to flying rep- 

 tiles. If, then, I can prove to you that reptiles could fly, without 

 which the comparison would be incomplete, you will see that the 

 comparison between reptiles and birds is not so impossible as it might 

 at first sight and sound appear to be. There is an advantage in 

 comparing two things that are supposed to be so dissimilar as reptiles 

 and birds, that we shall thereby more plainly see that grand unity of 

 plan, that sublime oneness that pervades all animate nature. Every 

 living thing with which we are familiar is constructed, and designed 

 upon that one plan, which is godlike. So far is this of advantage to 

 the observer of natural history, that I am convinced it is the only 

 ■channel by which observations upon nature can by any possibility 

 lead up from the things created to the creative power. If we do not 

 Appreciate that one distinctive feature, the oneness of the plan, and 

 the variety contained in that oneness, it is impossible to have the 

 same grand feeling of worship for the powers of creation. 



I will then endeavor to show you the machinery of life ; the life- 

 machinery of the reptiles and the birds ; my object being to convince 

 you of that unity to which I have just alluded. The frame-work by 

 which we compare one creature with another is designed for a spe- 

 cific purpose ; that purpose being to contain and to protect the vital 

 organs ; it is therefore secondary in character to the vital organs, 

 which it is designed to protect. I will endeavor, in the fii'st instance, 

 to represent to you the vital organs of a reptile, and the same of a 

 bird, for the purpose of bringing before you an intermediate form. 

 It has been said by naturalists, Mr. Darwin among the number, that 

 the geological record, containing the remains of the forms of life that 

 are called extinct, is so imperfect that we have no direct evidence of 

 an intermediate form. It is extraordinary that he, of all other per- 

 sons, should make such an assertion. Intermediate forms are numer- 

 ous. But I beg to observe that their recognition is very dependent 

 on om* degree of faith in the persistence of species. If there be inter- 

 mediate forms, and particularly in relation to those forms that have 

 passed away, you will at once perceive my object in placing before 



