14 KANSAS Academy of Science. 



tomical history from the comparative standpoint. This will lead us to a better 

 understanding of the unfoldings and unfoldings, through past germinal forms, 

 through which the human face has come, up to the perfect flower of to-day. 



We notice at the outset that the subject of the enibryologieal history of man is 

 greatly misajjprehended, although, as we have noticed before, it is simple in its prin- 

 ciples, when studied from the evolutionary and comparative standpoint. We have 

 been a long time in accepting the self-evident fact that the human embryo passes 

 through stages of evolution that recall and illustrate the growth of the species; for 

 the growth of the embryo is, in fact, an epitome, a panorama in miniature, of the 

 growth of the species. It presents, at various and successive steps, conditions and 

 parts which are permanent in lower animals. At first it resembles the very lowest 

 forms, then those next higher, then those still higher, and then again higher, until 

 its own type is reached, when its form, in turn, becomes permanent. Its growth 

 simply illustrates the growth of the species, and, by graded stages of resemblances, 

 points out the path by which its own type was reached in the evolution of the spe- 

 cies. But simple as this fact is, it remained unrecognized for long years, and is, in- 

 deed, understood by but few intelligent people even now. Prof. Ernst Haeckel, in 

 "Evolution of Man," writes at length of '"Anthropogeny," as the evolution of man is 

 christened. "It is surprising," he says, "to see what a little way the knowledge of 

 human evolution has spread, even among the very students of nature." Or again 

 ("History of Creation"'): "The facts of embryology would alone be sufficient to 

 solve the question of man's position in nature, which is the highest of all problems, 

 for their philosophical importance cannot be too highly estimated. He proceeds to 

 explain this important branch of science, and begins: 



"Our first principle of biogeny is, the evolution of the germ is a condensed evo- 

 lution of t"he tribe, and the reproduction is more complete in proportion as, in 

 consequence of constant heredity, the original inherited evolution is more closely 

 realized." 



Haeckel again says ("Evolution of Man'"): "At a certain period in the develop- 

 ment of the human embryo it has essentially the anatomical structure of a lancelet, 

 later of a fish, and, in subsequent stages, of amphibian and mammal forms; in the 

 further evolution of these mammal forms, those first appear which stood lowest in 

 the series, such as the forms allied to the beaked animals {ornithorhynchus); then 

 those allied to the pouched animals (marsupialia), which are followed by forms most 

 resembling apes, till at last the peculiar human form is produced as the final result." 



The embryology of the face is not difficult to follow. It is conceded that its main 

 elements are formed from the remains of the gill arches of the fishes and early ver- 

 tebrate amphibious forms. In the early embryonic condition of the higher verte- 

 brates, including man himself, we find on each side of the neck several gill slits, each 

 with its gill arch. Mr. R. R. Wright ("Standard Natural History") says: "In the 

 aquatic vertebrates the anterior part of the alimentary canal communicates with the 

 outside by a series of gill clefts on either side, through which the water streams for 

 respiratory purposes. Although these gill clefts shortly disapper, with the exception 

 of the first, in the air-breathing vertebrates, yet they are present in the embryos 

 of all, even of the highest. Between the clefts (also known as the visceral clefts) 

 are solid pillars, visceral folds, which are not developed in the higher forms, except 

 in the first and second arches, the rest being suppressed or nearly so. An actual 

 fusion takes place between the upper arch and the cranial skeleton to form the up- 

 per jaw, while the second arch is modified into the lower jaw, the Meckelian part, 

 which is hinged to the upper jaw and suspended from it." From this orgin the 

 jaws are developed in all the higher forms, man included. In the human embryo 

 the origin of the face and jaws is well indicated, the gill clefts being quite conspic- 



