VOt. XLIV.]- PHILOSOPHICAL TRANSACTIONS. 201 



choidesj luteovirens, vulgare, majus, capitulis erectis : Raii Synops. ed. 3, p. 48. 

 Hypnuin vulgare, sericeum, recurvum, capsulis erectis cuspidatis, Dill. Hist. 

 Muse. 323. It is frequent on old walls, and there is a specimen of it in the 3d 

 vol. of the Hortus siccus of English plants of my collecting. 



The head of this moss appears to the naked eye, as at fig. 7, of a pale-brown 

 colour, and smooth surface, and is in part covered with a membranaceous ca 

 lyptra, resembling in shape an extinguisher, or a funnel inverted. When this 

 calyptra is taken off, and the head placed before the microscope, the surface is 

 seen to be ridged with longitudinal striae, the basis of the head of a dark orange- 

 colour, and more opaque than the rest ; and the top is bounded by an orange- 

 coloured ring, swelling out something beyond the surface of the contiguous parts 

 of the head. A close observation and good glasses have showed, that in this little 

 head there are not wanting the parts essential to the fructification of what are 

 commonly called the more perfect plants. 



This ring is truly a monophyllous undulated calyx ; and within it arise 1 6 py- 

 ramidal fimbriated stamina : these are of a pale-greenish colour, and are loaded 

 with a white oval farina : the stamina all bend toward each other from their bases, 

 and almost meet in a point at their tops. This is their appearance when the 

 head is nearly ripe, as expressed at fig. 8. And immediately under the arch, 

 formed by these stamina, is placed a slender, cylindrical, hollow pistillum, 

 through which the farina makes its way, and is dispersed among the seeds 

 in the head. The external membrane of the head is a continuation of the 

 outer covering of the stalk, and is strengthened at its basis by 4 or 3 ribs, which 

 soon lose themselves in the striae. 



A longitudinal section of the head shows, that the membrane before men- 

 tioned incloses a seed-vessel so large as to fill it every way : in most places they 

 touch ; but wherever they do not, a number of very slender, white, and trans- 

 parent fibres show themselves, which join them together. This seed-vessel is 

 filled with perfect and very beautiful seeds ; they are round, transparent while 

 unripe, but afterwards opaque, and of a very beautiful green ; which colour they 

 retain even when dried. 



The number of seeds in one of these heads is astonishingly great : he often 

 attempted to count them, in such as were fiill, and out of which few or none 

 had been dislodged by the cutting ; and found the number amounted to no less 

 than 13824. Fig. Q shows a longitudinal section of the head with the seeds, 

 the stamina, and the joining of the capsule with the external membrane of the 

 head. 



The stamina, examined alone, afford a most pleasing sight ; they are com- 

 posed of a white transparent substance, of a pyramidal figure, every where co- 

 vered with a pale-greenish crust ; which is the receptacle of a vast quantity of an 



VOL. IX. D D 



