5° 



PROCEEDINGS OF THE 



between the two last states, but there was not sufficient certainty 

 as to the order of these staj^es to justify his putting them on 

 record at present. He believed that in this free-packet stage 

 the walls, though finely sculptured, were not or only imperfectly 

 silicified and capable of expansion and growth. His belief was 

 grounded on the observation that all such early stages disappeared 

 on "cleaning" with nitric acid; but he pointed out that there 

 could be no certainty on this point unless after direct observation 

 of individual cases — a matter involving difficulties of manipulation 

 he had not yet overcome. Finally, there were shown two dia- 

 grammatic figures of the same filament of Chcetoceras decipiens as 

 observed in successive stages of contraction of the cell-contents, 

 their rounding-off, and the production by free cell-formation of 

 eight spore-like bodies. 



In the case of Biddulphia and Ditylum and in the first case of 

 Co scino discus, where one new diatom was produced, it appeared 

 to be merely a case of so-called rejuvenescence of the parent cell. 

 In the case of Coscinodiscus, where preliminary divisions of the 

 contents into eight and sixteen took place, it appeared to be 



reproduction by the free cell- ^ 



formation of new diatoms, in ^■ 

 their early stages capable of 

 growth. In the case of Chcs- 

 toceras the state of things 

 resembled Coscinodiscus, but 

 difiered from it since merely 

 spore-like bodies were formed 

 so far as had been observed. 



In all cases, whether one 

 new diatom or two, or eight 

 or sixteen were formed within 

 the parent, the result was a 

 reproductive process of a kind 

 not yet recorded in Diatoms 

 except in the single case of 

 the occurrence of a young 

 Siddulphia aurita wathin the 

 parent as observed by Prof. 

 Cleve, and of the instances 

 cited by Mr. Comber. 



Mr. M. ¥. Woodward exhi- 

 bited three specimens of the 

 African Mud-fish {Protopte- 

 rus annectens) killed in the 

 torpid state within their mud- 

 burrows, which were presented to the E-oyal College of Science, 

 London, by Dr. H. O. Forbes, Director of the Liverpool Free 

 Public Museums. He especially drew attention to one of 



