] 



438 MK. C. T. BRUEUY OS A IN'EW INSTA]^CE 



as it was mainly upon tLese attenuated divisions that the pro- 

 tlialli were formed, the points running out into threads at the 

 ends of which tlie prothaUi appeared, it struck me that as these 

 attenuated pinnae were not confined to this individual Polysti- 

 clium, others presenting the same peculiarity might develop the 

 rest of the phenomena under suitahle treatment. I consequently 

 applied to Colonel Jones, of Clifton, for whose aid throughout 

 these investigations I cannot too strongly express my thanks, and 

 was duly furnished with a young plant of the form known as 

 P. angulare var. pidcTierrimitm^ Wills, found by the late Dr. Wdls 

 in Dorsetshire some years ago. This form, which, it will be 

 noted, was found some seventy or eighty miles distant from 

 Mr. Padley's station, moreover differs markedly in general cha- 

 racter, so that no doubt can reasonably be entertained of its 

 distinct origin ; the characteristic prothalloid extensions had also 

 never heen remarked upon it. 



On receipt of the plant early in the present year (18S6), 1 at 

 once placed it in a close Todea frame, with the result that as soon 

 as the fronds attained the length of some 6 inches or so, I was 

 delighted to find the tips 'of the pinnules running out and dilating 

 into prothalli in profusion, until the pinnae were absolutely fringed 

 with them, precisely in the same manner as in Padley's form. 

 Later in the season, however, the close treatment disagreed 

 with the plant, and on removal from the frame to a cool 

 fernery, the prothalli dried up and perished ; fortunately, how- 

 ever, not before Prof, Bower was able to inspect the plant and 

 obtain material for further investigation. It seems highly pro- 

 bable from the rapid disappearance of the prothalli, in this case 

 under nearly normal conditions, that they would not be deve- 

 loped under ordinary circumstances to an extent likely to attract 

 observation. 



So far the phenomena observed had been precisely similar 

 to those noticed in Padley's form ; but upon further close exami- 

 nation of the fronds I was struck by the existence of several 

 hydraform bodies, clearly visible to the naked eye, which 

 appeared to be attached to the upper surface of the pin- 

 nules well within the margin, and in this respect, as well as 

 in their shape, entirely difierent from the prothalliform pomt- 

 extensions. . 



On examining several of these under the microscope, I found 

 their distinct character emphasized by the fact that they vvere 



