38 H. J. Clark on the Microscope. 
of the cell. The double ~_ —— as is said, from the fact 
cate cone, which, when Iioonushs 
Fig. 1. 
endwise, presents to the eye ‘ 
gd f echa 
two circular ends concentrically ; are 
the broader end, which i ays eae itt 
§ 
jm} 
= 
0g 
Touma 
° 
a. > 
a>) 
=] 
(ar) 
eo 
oO 
= 
_— 
~ 
Pet 
S 
o 
po 
=| 
the narrower end to the inner cir- 4 
cle (a). - Thus are these dots de- iti 
scribed and illustrated, by Mohl, oe 
Schleiden, and Schacht, as seen in 
the common European Pin e (Pinus 
sylvestris), and thus did they always 
appear to me, not only in that spe-. 
cies, but also whe bserved 
them in Pinus Strobus, except with 
this ditieaaeas that the perforation 
was boun y an exceedingly 
faint gl circle, (C, c,) whose re- 
lations I could not comprehend, 
nor was | able to eosoneite its pres- 
ence with the theory in regard to 
the nature of the perforation. I aR 
therefore left it, doubtingly sup- 9% f¢9 
posing it to be some optical illusion. The microscope which I 
used, and which I have wenn in the habit of using up to within 
io} 
the last six months, is an O made for Prof. Agassiz 
some years ago; and yet at this very day) I find it as good, with 
perhaps a single exception, as any now made in Germany, an 
therefore just as trustworth y in the Sah orc of the glandular 
dots of the Pine.* 
* Tt may not be Faventeasont to state here, that the first Pe ng ets 8 made 
in Germany was ¢ sate peter 1839 by Fraunhofer, for ree iz. This 
this mas i mae ss 
ee ie pig work with rie SN gine the 
has ae evident to Agassiz that his instrament 
which the progress of his researches put 0 it; 
was something beyond its eed of. aelt bere hig au get a 
peste se Rey fo. waren him in the belief that pag asceite 
Fab hardly 
— sper as 1852 he opportunities to see the wor 
the English he ba opp ; and although it oe lamn en ao rival of, t 
