144 Transactions of the 



find it on the surfaces by soaking the masses and examining the 

 outside crust in water. Most of the sand and dirt was in this way- 

 washed out, and lying in some of the crevices could be seen a little 

 blackish fiocculent matter, which was gently torn away with fine 

 forceps, removed to a slide, and mounted. This fiocculent substance, 

 apparently, contained some of the broken and coarse threads of the 

 plant, but evidently the entire plant did not grow on the surface of 

 the incrustation, for in no case was it discovered in this loose matter, 

 but always on solution of the inorganic substance. The deposit from 

 the washings of the moss was now treated with diluted acetic acid 

 and very carefully examined in small quantities under the micro- 

 scope, but only a very few disjointed heads and minute portions of the 

 mycelium threads were seen amongst fine, quite decayed vegetable 

 structures, the former of which were possibly from the abraded 

 parts from which the pieces had been sawn, and those exposed on 

 removing the mass from the bed where it was formed ; hence why 

 the term apparently, has been used in reference to those portions 

 of the fiocculent substances found on the outside. 



Several fresh pieces were again sawn from the mass and dis- 

 solved in weak acetic acid ; the fiocculent bits as well as the organic 

 debris were very carefully examined in small portions at a time. The 

 entanglement of the long threads or tubes of the little plant and the 

 sort of network it appeared in most cases to form around or upon 

 the decayed moss structure, just opened up the question whether . 

 the plant may not have originally been parasitic on the moss ; but 

 tracing the threads in some cases more than a quarter of an inch, 

 some part of the coarser portion of the tubular stem was generally 

 found attached to a little mass of a soft dark-brown substance 

 (? humus) which had resisted the action of the acid, but which broke 

 up directly under the needles, for it was only by considerable 

 patience that the vegetable debris of the moss could be cleared away 

 from these long, much-branched, interlacing threads, or could be 

 cleaned so as to furnish a more or less satisfactory specimen for 

 figuring, and then always with the loss of some of the little heads 

 or sacks at the tips of the branches. 



Comparing the plant with the figures at hand of Botrydium 

 granulatum, and notably the excellent one by Mr. E. Parfitt, in the 

 January number of ' Grevillea ' ; the conceptacles or heads of the 

 plants were seen to be very much more minute ; Botrydium granu- 

 latum being described as of the size of a pin's head, whilst these 

 average from 2 to 6 one-thousandths of an inch. Again, many of 

 the heads, though having more or less the shape of Botrydium, are 

 not as sessile, but are borne at the ends of fine long tubes as in 

 mucor ; others again being very sessile, almost seated on the tubes ; 

 others being intermediate ; whilst the dense strong-looking root 

 threads or tubes furnished a resemblance justly in favour of Mr. 

 Renny's and Mr. Currey's opinions, to which the writer gladly con- 



