188 BRITISH CICADiE. 



whilst few would deny the inferences from the facts 

 of a persistent fertility. 



The evidence from the rocks must be looked upon, 

 jrro tanto, — rather as negative to the transmutation of 

 species. But biological phenomena, like many other 

 phenomena, require often only a modicum of time for 

 showing results. In the insect world one might well 

 marvel (except that the fact is so common) at the 

 wonderful atrophy of the alimentary organs, tracheae, 

 and legs of the caterpillar, and the simultaneous deve- 

 lopments of wings, ocelH, and reproductive parts in the 

 pupation of some butterflies, which changes sometimes 

 require only four or live days for completion. Phe- 

 nomena like these may give consistency to a belief in 

 sudden leaps, with no perceptible transition, from one 

 generation to another. M. Naudin and other com- 

 petent thinkers have discussed this point, and Darwin 

 does not entirely ignore such a possibility of sudden 

 bounds. 



Without prejudicing the question one way or the 

 other, Prof. Fiay Lankester's remarks may be sum- 

 marized, though they were not used by him for the 

 same purpose. Some animals which ordinarily, in 

 allied species, pass through a larval stage, may in 

 certain kinds miss this stage altogether. Thus some 

 of the little tree-frogs have no tadpole forms. " There 

 are instances in which the most important part of the 

 recapitulative phases are absent from the develop- 

 mental history of an animal. All the wonderful 

 changes in an animal's ancestry may be completely 

 omitted."* 



Thus, granting the possibility of the transmutation 

 of species, numerous intermediate links might be 

 passed at a bound, and hence their absence in the 

 rocks. The question, however, may be asked. Why is 

 this absence of transitional forms the rule, and without 

 perhaps an unchallenged exception ? 



In relation to the above remarks on the phenomena 



'■' See ' Degradation,' Prof. E. Kay Lankester, p. 53. 



