248 SCIENCE PROGRESS. 



antheridia and archegonia, accompanied by aerial roothairs, 

 the frond itself thus assuming the functions of the pro- 

 thallus. Mr. Lowe raised a number of similar plants on 

 the genesis of which he is preparing a paper which I will 

 not forestall ; but he informs me that in time they throw 

 off this aposporous character. Fronds which he has sent 

 me, and which I have laid down, have developed prothalli 

 all over their surface and at all terminals, but so far my 

 cultures are too recent to permit me to report the advent of 

 plants. 



This completes the sketch of the cases which have 

 come under my immediate notice, but considering that, in- 

 cluding the first discovery, the phenomenon has been 

 observed in no less than nine instances in our limited num- 

 ber of British species, viz., Lastrea [Nephrodium) two, Athy- 

 rium filix fcemina two, Polys tic hum angular e three, and 

 Scolopendrium vulgare two ; it is only reasonable to ex- 

 pect that many undiscovered instances must occur in the 

 innumerable other species existent throughout the world. 



Charles T. Druery. 



