Report on Zoology. 



139 



relations among the three sub-kingdoms of invertebrates 

 which have not usually been acknowledged ; but that one 

 should attempt to prove structure kinship between some 

 of the very lowest of the invertebrates and the vertebrates is 

 in the highest degree revolutionary, for under all systems 

 it has ever been conceded that there is a great gulf be- 

 tween the vertebrata and invertebrata. 



Four years ago, Kowalewsky raised the issue of the ho- 

 mology of certain parts of the larva of ascidians with the 

 chorda dorsalis of the embryo of the vertebrata. His observ- 

 ations and facts have been abundantly confirmed dur- 

 ing the last year by Prof. Kupfer, whose researches have 

 fully established the accuracy of his predecessor in these 

 investigations. 



All these valuable papers, whatever may be the truth of 

 the observations of the authors, indicate the absolute ne- 

 cessity of investigations of greater accuracy than those to 

 which naturalists have yet attained, before some of the 

 most essential questions in classification can be fully settled; 

 and the recent advances in the systematic study of living 

 forms suggest, if they do not promise, important assistance 

 in solving some of the vexed questions in biology. 



At a meeting of the British Association held at Liver- 

 pool, during September last, the paper which excited the 

 greatest interest among naturalists was the address of the 

 president, Prof. T. H. Huxley, the subject of which was 

 " Spontaneous generation." After a somewhat elaborate 

 review of the varied fortunes of the doctrine from the 

 experiments of Needham about 1750 to the supposed com- 

 plete refutation of his doctrine by Spallanzani, to the 

 repetition of the experiments under new conditions by 

 Schulze and Schwan in 1836-37, to what the professor 

 regarded as the final and conclusive experiments of Schroe- 

 der and afterward of Pasteur, he sums* up the chain of 

 evidence by expressing the firm conviction that no such 



