158 CORRESPONDENCE OF RAY. 



them will keep out this. Mr. Watts having a new con- 

 trivance (at least in this country), viz. he makes under 

 the floor of his greenhouse a great fire-place with grate, 

 ash-hole, &c., and conveys the warmth through the whole 

 house by tunnels, so that he hopes, by the help of weather- 

 glasses within, to bring or keep the air at what degree of 

 warmth he pleases, letting in upon occasion the outward 

 air by the windows. He thinks to make, by this means, 

 an artificial spring, summer, winter, &c. 



London, November 11, 1684. 



Dr. HANS SLOANE to Mr. RAT. 



SIR, The Fungus Campaniformis niger multa Sem. 

 plan, in se continens of Merrett's Pinax \Nidularia cam- 

 panulata, With.], grows plentifully here in several places 

 in London, and seems to me very pretty in the contriv- 

 ance of the seed ; for within the cup of the fungus, which 

 is like a bell, or rather the top of Muscus Pysoides, or 

 Pixidatus Ger. [Scyphophorus], there lies several seeds 

 fastened to the bottom of the cup by means of a very 

 small thread, or fibril, which I suppose might bring 

 the sap from the root to the seed : it has but a small 

 root, and usually comes out in a round white tumour from 

 old wood, which serves to keep up the sides of borders ; 

 the rain falling into this cup, and filling it, the seeds are 

 heaved up and washed over, and sow themselves. Per- 

 haps this Fungus may have a near affinity with the common 

 Muscus Pixidatus, and this may have some seed too. This 

 Fungus is figured by Menzelius in his description of some 

 plants in several places of Germany. Its name, or what 

 he says of it, I do not now remember, not having the 

 book by me. If you have not taken notice of this Muscus 

 or Fungus, I will observe it more narrowly and send you 

 its history. Yesterday I was at Chelsea Garden to see 

 how the plants were preserved there this cold weather, 



