318 PROCEEDINGS OF SOCIETIES. 



openings in the same, as they appeared, on being transversely 

 viewed, to form lines (or strife) passing inwards in a radial direc- 

 tion. In the living state Mr. Archer had very rarely been able 

 to see pseudopodia, and but extremely sparingly protruded ; it 

 must be assumed that these made their way outwards through 

 the minute tubular perforations in the outer envelope. In the 

 specimens now under view (there were two on the slide) he 

 thought a nucleus or " capsule " could, be readily enough per- 

 ceived, but, contrary to almost universal experience in similar 

 cases, it might be said to have taken no dye from the carmine 

 solution. The chief action of the fluid seemed to be that the 

 central body- mass became contracted and completely withdrawn 

 from the outer envelope in an externally more or less " crumpled " 

 manner, the outer envelope remaining unaltered, showing these 

 were quite differentiated portions of the structure ; indeed, in a 

 few instances, now and again, the empty, colourless and hyaline 

 wall, then almost glassy looking, had been met with, and still 

 retaining its quite globular figure. The question becomes, to 

 what existent genus could this be referred ? Of course the 

 genus Astrodisculus (Greeff') at once suggests itself; but two 

 other forms, two or three examples only of which Mr. Archer 

 had ever seen, and which he had tliought must be referable to 

 Greeff"s Astrodisculus, did not agree with the present form in 

 some particulars. Grreeff", indeed, ascribes to his Astrodisculus a 

 porous and siliceous envelope — those previously found by Mr. 

 Archer, very like, if not truly (?) referable thereto, had soft 

 envelopes (destroyed by sulphuric acid) . As regards the present 

 form the envelope doubtless appeared porous, but Mr. Archer had 

 not yet met with examples sufficient to experiment satisfactorily 

 with acids ; he had more than once tried to treat this form with 

 reagents, but lost the specimen in the eff'ort (they often will 

 vanish from sight out of sheer cross purposes !) ; he must, there- 

 fore, relegate it to the future, in hopes this form may again turn 

 up, when he would claim for it once more some attention from 

 the Club. 



IQth February, 1874. 



Remarks on Sairs of Platycerium. — Dr. Moore exhibited the 

 beautiful stellate hairs which closely cover the whole surface of" 

 Platycerium grande. These were mostly 9-rayed, and were seen 

 to good eff'ect when polarized. Dr. Moore observed that these 

 hairs revealed to us an adaptability of a wonderful nature, enabling 

 the plant not only to control too rapid transpiration from the 

 fronds during dry weather, but, he believed, to imbibe moisture 

 from the atmosphere as well. He knew that it was a disputed 

 point amongst physiologists whether plants were able to imbibe 

 moisture through their leaves ; some experiments lately made tend 

 to prove they have no such function, but botanists, whose testi- 

 mony is valuable, including the late Dr. Lindley and Dr. Asa 

 Gray, believe that plants have the power of imbibing moisture 



