102 W. B. CARPENTER ON THE STRUCTURE OF ORBITOLITES. 



One more point is the very remarkable reparation which takes 

 place when these disks are injured. Sometimes they may be nibbled 

 by Fishes, Crustaceans, or Echinoderms ; or they get broken by the 

 dashing of the waves : and when this occurs, there is always a curious 

 tendency towards the restoration of the circular form by an exuda- 

 tion of protoplasm, which forms a complete ring round the broken 

 edge, and subsequently becomes surrounded by more regular annuli. 

 A mere marginal fragment is quite sufficient to be the centre of such 

 a new growth, reproducing a perfect disc (Fig. 12) ; this reparation 

 always taking place on the perfected type, just as Sir James Paget 

 has observed that repair always takes place in accordance with the 

 existing state of the animal. I cannot think it is possible to resist 

 the conviction that this reparation takes place on a plan, and is not 

 the result of mere casualty. 



These Orbitolites seem to be the culmination of the Porcellaneous 

 series of Foraminifera, not leading up to anything else. It is 

 my belief that they form the top story of these simple sarcodic 

 forms. 



The results of this inquiry, I think, will show you the value of 

 taking up a subject, and working it out thoroughly ; and I hope this 

 lesson will not be lost on many now present. Before entering 

 upon such a special inquiry, however, everyone should go through 

 a general course of instruction. It is now admitted that in every 

 profession requiring the exercise of mental power, general training 

 is of great importance to begin with ; and in the case of anyone 

 desiring to follow up some special object of microscopic study, I 

 would recommend such a general preliminary course. Having 

 made himself acquainted with the microscopic characters of any 

 group as a whole (using for the purpose, when suitable, the bino- 

 cular as well as the monocular), I would then recommend the 

 student to take up some special subject, the detailed pursuit of 

 which will be found to open out lines of thought and inquiry of far 

 more value to himself and to science than the sort of dilettante 

 work which is still so often indulged in. Thirty years ago, when 

 Schleiden brought out his great work on Botany, he supposed that 

 there were no good microscopes in England, because so little had 

 been done in this country for the elucidation of vegetable structure 

 and life-history ; but the fact was, we had here the best micro- 

 scopes of the day, the fault lying with the workers. I rejoice, 



