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conveyed to the female filaments in the manner suggested ; he thought that 

 the case was more likely to be a parallel one to that of plants, where the 

 pollen of the male flowers was produced in great quantity because it was 

 most likely that some of it would get lost, and therefore a large supply was 

 provided. He thought it was quite likely that a similar arrangement held 

 good in the case before them, only that as the fertilizing element was 

 thrown out into the water many frustules were provided in order that some 

 of them at least might get some of it. In all the male frustules it would 

 be found that after fertilization a division into two parts took place, the 

 upper half falling away — and it would also appear that after contact there 

 was an opening through which the fertilizing medium might escape. He 

 had little doubt that the fertilizing medium being quite free came into con- 

 tact with the non-silicious band and passed through it. 



The President said he had never made diatoms a special study himself, 

 but Mr. Thwaites was an early friend and pupil of his, and it was very much 

 in consequence of his earnest recommendation that he should take up the 

 study of the unicellular plants, that the observations were commenced 

 which led to the discovery of conjugation — and during the interval of 45 

 years very little beyond this seemed to have been done. He had always 

 said that if one-tenth part of the time had been given to the life history of 

 these forms which had been spent in trying to make out the strige on their 

 valves, very much better results would no doubt have followed. He did 

 not recollect anything at all approaching to the description which Mr. 

 Buffham had given of these males attaching themselves to the female forms. 

 The nearest thing seemed to be what was seen in the case of the conjugatas, 

 where in one group the endochromes of both discharge themselves into the 

 intermediate space ; or, on the other hand, in those cases where the 

 endochrome of one filament passed over into the cells of the other filament. 

 He thought, however, that there had been something lately recorded in the 

 " Journal of the Eoyal Microscopical Society " which tended to show that 

 this was not quite correct, and this had rather sent them adrift again upon 

 the question. If the observations which had been described that evening 

 should prove to be the first indication of sexuality it would be of the 

 greatest importance. What was now wanted was some information as to 

 the existence of a distinct opening being formed, so that it could be affirmed 

 that there was an actual passage. Mr. Buffham inferred that there was, 

 because of the effects which took place ; but he should very much like to 

 know that it had been proved by observation. He hoped that Mr. Buffham 

 would devote further attention to this point, which he regarded as one of 

 the very highest interest ; if proved it would form one of the pregnant facts 

 of biology ; and such being the case, it was worth any amount of attention 

 which it was possible to bestow upon it. He could only express the very 

 highest sense of the value of such an observation. 



Mr. Buffham said with regard to the point on which Dr. Carpenter had 

 some doubt, he could only ask, how was it possible to account for the facts 

 except by taking his view of the attached frustules ? And why should 

 they lose their vitality in the way he had described ? Absolutely without 

 exception they had never observed the formation of sporangia unless they 



