770 REPORT— 1900. 



From the natui'e of things it is clear that the voice of the palaeontologist can 

 only be heard on the morpholngical aspect of the question, but to many of us, 

 including myself, the morphological argument is so convincing that we believe 

 that even if the Darwinian theory were proved to-morrow to be utterly baseless, 

 the Doctrine of Descent would not be in the sligbtest degree affected, but would 

 continue to have as firm a hold on our minds as before. 



Now as Palaeontology takes us back, far back, into the life of the past, it 

 might bo reasonably expected that it would throw great light on the descent of 

 animals, but the amount of its evidence is necessarily much diminished by two 

 imfortunate circumstances. First, the terrible imperfection of the geological 

 record, a fact so obvious to any one having any acquaintance with Geology that 

 it need not be discussed here ; and secondly, the circumstance that save in very 

 exceptional cases only the hard parts of animals ai-e preserved, and those too oftep 

 in an extremely fragmentary and disjointed condition. But though we cannot 

 expect that the palseontological record will ever be anything more than fragmen- 

 tary, yet the constant occurrence of new and important discoveries leads us to 

 entertain the hope that, in course of time, more and more of its pages will become 

 disclosed to us. 



Incomplete, however, as our knowledge of Evolution as derived from 

 PahBontology must be, that is no reason why we should not appraise it at its 

 proper value, and now and again stop for a moment to take stock of the material 

 which has accumulated. 



You are all already acquainted with the telling evidence in favour of Evolution 

 furnished by the well-known series of Mammalian limbs, as well as of teeth, in 

 which the progress, in the course of time, from the more general to the n.ore 

 special is so obvious that I cannot conceive of any unprejudiced person shutting 

 his eyes to the inference that Descent with modification is the reason of these 

 things being so. Suppose, then, that on this occasion we take up the palseonto- 

 logical evidence of Descent in the case of fishes. This I do the more readily 

 because what original work I have been able to do has lain principally in the 

 direction of fossil ichthyology ; and again, because it does seem to me that it is in 

 this department thnt one has most reason to complain of want of interest on the 

 part of recent biologists, even, I may say, of some professed palaeontologists 

 themselves. 



But the subject is really of so great an extent that to exhaust it in the course 

 of an address like the present would be simply impossible, so I shall in the main 

 limit myself to the consideration of Palaeozoic forms, and this more especially see- 

 ing that we may hope for a large addition to our light on the fishes of the more 

 recent geological formations from the fourth volume of the ' Catalogue of Fossil 

 Fishes ' in the British Museum, which will soon appear from the pen of my friend 

 Dr. A. Smith Woodward. I need scarcely say how much his previous volume has 

 conduced to a better knowledge of the Mesozoic forms. 



Here I may begin by boldly affirming that I include the Mar.sipobranchii as 

 fishes, in spite of the dictum of Cope that no animal can be a fish which does not 

 possess a lower jaw and a shoulder-girdle. "NVhy not? The position seems to me 

 to be a merely arbitrary one ; and it is, to say the least, not impossible that the 

 modern Lampreys and Hags may be, as many believe, the degenerate descendants 

 of originally gnathostomatous forms. 



To the origin of the Vertebrata Palajontology gives us no clue, as the fore- 

 runners of the fishes must have been creatures which, like the lowest Chordata of 

 the present day (Qrochorda, Hemichorda, Cephalochorda), had no hard parts capable 

 of preservation. And though I shall presently refer again to the subject,! may 

 here affirm that, so far as I can read the record at least, it is impossible to derive 

 from Palaeontology any support to the view, recently revived, that the ancient 

 fishes are in any way related to Crustacean or Merostomatous ancestors. 



What have we then to say concerning the most ancient fishes Vkith which we 

 are acquainted ? 



The idea that the minute bodies, known as Conodonts, which occur from the 

 Cambrian to the Carboniferous, are the teeth of fishes ai:d possibly even of ancient 



