56S 



THE POPULAR SCIENCE MONTHLY.— SUPPLEMENT. 



two very discreet persons were observed to walk 

 out. If they had staid, they would probably 

 have carried away nothing worse than a more or 

 less hazy notion that Haeckel and Von Baer were 

 very great men, and that the amphioxus and 

 ascidians have become families of much greater 

 consideration within late years. From indica- 

 tions we shall presently have to mention, it seems 

 that Plymouth orthodoxy is still susceptible on 

 the topic of evolution ; and it might perhaps have 

 had a calming effect to assure the good citizens 

 of all respectable denominations that the am- 

 phioxus is a particular bete noire of those partic- 

 ularly naughty people the positivists. We have 

 not heard, however, that Prof. Huxley has been 

 in high favor at the Vatican since Dr. Congreve 

 put him under the ban of Humanity. 



To return to Prof. Allen Thomson, the gen- 

 eral tenor of this more special part of the ad- 

 dress was to set forth the parallel between the 

 development of kinds, as conceived by the Dar- 

 winian naturalist, and the embryonic develop- 

 ment of the individual as it may be seen in any 

 of the higher animals, from the microscopic 

 ovum upward through the various stages that 

 lead to the finished form. On the evolution hy- 

 pothesis, every such stage is the record of a con- 

 dition once present in adult ancestors of remote 

 generations ; and this furnishes an explanation — 

 how complete must be left for specialists to de- 

 cide, but certainly the only explanation yet known 

 — of phenomena in embryonic life which other- 

 wise seem purposeless and unaccountable. Prof. 

 Allen Thomson left no doubt as to his own opin- 

 ion ; he pronounced the evidence of embryology 

 in favor of the continuous development of species 

 to be not only strong, but practically conclusive. 

 It is impossible for an embryologist not to be an 

 evolutionist; no theory which does not include 

 the leading ideas of evolution — namely, variabil- 

 ity, adaptation, and hereditary transmission — can 

 bring the facts of embryology within a general 

 law. The connection and continuity of all or- 

 ganic life force themselves irresistibly upon the 

 "faithful student," him who follows, according 

 to Plato's precept, whithersoever the reason of 

 the thing leads him, not looking to the right hand 

 or the left. 



Such were the general features of the address, 

 which, valuable as was the matter, somewhat 

 failed, as we have said, in immediate effect. It 

 was read with a tone of calm and equable famili- 

 arity proper for a discussion among experts, but 

 hardly calculated to fix the attention of a mixed 

 audience on the details of embryonic develop- 



ment. There was likewise another drawback, 

 and one wholly beyond the president's control. 

 The wise men of Plymouth seem to regard Dar- 

 winian doctrine as dangerously strong meat for 

 their fellow-citizens, and the speeches that intro- 

 duced and followed the discourse of the evening 

 were apparently designed, instead of setting off 

 and heightening its effect, to extenuate it as much 

 as possible. The mayor introduced Dr. Allen 

 Thomson in a rambling oration (not unjustly re- 

 ceived with bare civility), in which he took occa- 

 sion to mention in an emphatic manner that, if 

 the British Association studies the book of Na- 

 ture much, the men of Plymouth study the book 

 of Revelation more. It is true that Plymouth is 

 distinguished above other towns for the variety, 

 vehemence, and eccentricity, of its sectarians. It 

 was reserved for the Mayor of Plymouth to dis- 

 cover that the temperament which has produced 

 three rival sets of Plymouth Brethren is peculiar- 

 ly favorable to the formation of a sound judgment 

 on scientific speculation. After this he launched 

 into a display of classical allusions, in which Ajax 

 and Prometheus got sadly mixed up. However, 

 Dr. Allen Thomson was Prometheus, and, if he 

 did not meddle with fire, nobody would peck him. 

 The suggestion of a " winged hound of Zeus " in 

 the background who tears presumptuous men of 

 science was not in the best taste. Then, after 

 the address, the Earl of Mount Edgcumbe pro- 

 posed the usual vote of thanks to the president, 

 and said he thought the wisest course for the 

 Association in such difficult matters as had been 

 put before them was to " take their president's 

 advice, and, instead of coming to rash conclu- 

 sions, reserve their judgment so long as that 

 branch of science remained in the region of hy- 

 pothesis." This was a pretty bold piece of ac- 

 commodation, considering that the president, so 

 far from giving any advice of the kind, had said, 

 as distinctly as words could say it, that in his 

 opinion only one judgment was possible. Wheth- 

 er the Earl of Mount Edgcumbe. really meant that 

 he disagreed with Dr. Allen Thomson on his own 

 ground, but did not like to say so, or whether he 

 had any more subtile meaning, we shall presum- 

 ably never know. Last came Dr. Acland to sec- 

 ond the vote of thanks, and professed himself 

 specially thankful to Dr. Allen Thomson for not 

 having trespassed " in a light and useless way " 

 on the forbidden ground of metaphysics. The 

 terms of this compliment seemed intended to im- 

 ply a censure on Prof. Huxley and Prof. Tyndall 

 for their well-known Belfast addresses, and to sug- 

 gest in a delicate way to the good folk of Plym- 



