546 THE POPULAR SCIENCE MONTHLY 



As it seems to me, the leading facts in embryology, which are second to 

 none in importance, are explained on the principle of variations in the many 

 descendants from some one ancient progenitor, having appeared at a not very 

 early period in life, and having been inherited at a corresponding period. 

 Embryology rises greatly in interest, when we look at the embryo as a picture, 

 more or less obscured, of the progenitor, either in its adult or larval state, of 

 all the members of the same great class. 42 



Yet poor Chambers is reproached for "baseless speculation" be- 

 cause, looking upon facts accepted by all the competent embryologists 

 of his time, he saw in them the meaning that Darwin afterwards saw, 

 and that so great a mind as Lyell's had been unable to see. In the 

 third edition of the " Vestiges," 1845, he wrote: 



First surmised by the illustrious Harvey, afterwards illustrated by Hunter 

 in his wondrous collection at the Royal College of Surgeons, finally advanced to 

 mature conclusions by Tiedemann, St. Hilaire and Serres, embryotic develop- 

 ment is now a science. Its primary positions are ... (2) that the embryos of 

 all animals pass through a series of phases of development, each of which is 

 the type or analogue of the permanent configuration of tribes inferior to it in 

 the scale. 



And in this Chambers found one of his chief evidences of trans- 

 formation of species. Elsewhere in this edition he devotes several pages 

 to the elaboration of the argument from recapitulation in the case of the 

 brain. " Taking as a basis the scale of animated nature as presented in 

 Dr. Fletcher's ' Eudiments of Physiology,' " he points out " the wonder- 

 ful parity observed in the progress of creation, as presented to our ob- 

 servation in the succession of fossils, and also in the foetal progress of 

 one of the principal human organs." 43 



8. The Argument from Rudimentary Organs. — In his "Lectures 

 on the Phenomena of Organic Nature," 1863, Huxley mentions as il- 

 lustrations of this type of evidence the foetal teeth of the whalebone 

 whale, the rudimentary toes in the horse's leg, the rudimentary teeth in 

 the upper jaw of the calf. He concludes : 



Upon any hypothesis of special creation, facts of this kind appear to me 

 entirely unaccountable and inexplicable; but they cease to be so if you accept 

 Mr. Darwin's hypothesis, and see reason for believing that the whalebone whale 

 and the whale with teeth in its mouth, both sprang from a whale that had 

 teeth, and that the teeth of the foetal whale are merely remnants — recollections 

 if we may so say — of the extinct whale. . . . The existence of identical struc- 

 tural roots, if I may so term them, entering into the composition of widely 

 different animals, is striking evidence in favor of the descent of those animals 

 from a common original. 



But from the same facts Chambers had argued to the same conclu- 

 sion nearly a score of years earlier. 



The baleen of the whale and the teeth of the land mammals are different 

 organs. The whale in embryo shows the rudiments of teeth; but these not 

 being wanted, are not developed, and the baleen is brought forward instead. 



a " Origin of Species," sixth edition, ch. XIV. 



^"Vestiges," third edition, 1845. 



