[50 
To confefs the truth, I was but very fuperficrally 
acquainted with this fpecies of Conferva till I had 
made the above difcovery j fince tlae defcriptions of 
it, which w'e find in the books of botany, by no 
means afford an adequate idea of the ftrucffure of the 
plant. Dillenius (.1 ), in his defcription of it, pre- 
tending to corretff Pliny, for a fuppofed impropriety 
in the term fijiulcfa d^nfitatls^ fiiys, that there is ix) 
cavity obfervable either in this or other larger fpecies 
of Conferva, excepting, perhaps, in his Conferva di- 
choioma [2) \ in which he is certainly miftaken ; fince 
the filaments of the common Conferva, when exa- 
mined with a good microfcope, evidently appear to 
be capillary tubes divided at equal diftances by paral- 
lel fepta or diaphrag[OiS, exadfly like the 25th fpecies 
of the fame genm in Dillenius’s Tables. Pliny’s (3) 
epithet, therefore, fo far from being improper, is a 
real charaderiftic of the thing in queftion. 
As the fyffematical botaniffs generally take their 
leading charaders from the external figures of plants, 
we need not be furprifed to find them inaccurate in 
their defcriptions of the fmaller tribes ; more efpe- 
cially as they negled the ufe of proper glaffes, by 
which alone they can acquire a knowledge of them. 
Dillenius and Linnseus himfelf have both been led 
into miftakes, from this omiflion. The former, in 
the preface to his Hijioria Mufcorumy confeffes, that 
he made ufe of common glaffes only, in order that 
the figures of the fmaller plants, which he was to 
(1) Hift. Mufc. Gen. i. Ord. i, Sp. r, 2. 
(2) Ib.Gen. 2. Sp. 9. (3) Hift. Nat. lib. XXVIL cap. viii. 
, reprefen t 
