The Moller Probe-Platte. By J. Edwards Smith. 241 
we must regard the measurement of No. 18 by lamp as little less 
than a feat. 
Measurement of Moller Probe-Platte, No. 25S. 
Numbers 
Lines 
counted. 
in 1-1000 
Eng. inch. 
1. Triceratium favus 
4 .... 
centre to centre of hexagons 
3-06 
4 
4 .... 
2. Pinnularia nobilis . . 
14 .... 
at edge from centre . . 
15 .... 
18 .... 
midway from centre to end 
.. top 12 ’5 
18 .... 
bottom 12 - 1 
3. Navicula lyra 
24 .... 
from centre along axis 
.. .. top 16 - 3 
25 .... 
.. bottom 17' 1 
29 .... 
short lines between marginal 
.. .. top 17-3 
31 .... 
bottom IS - 5 
4. Navicula lyra 
36 .... 
from centre along axis 
36 .... 
. . bottom 25 • 0 
36 .... 
short lines 
36 .... 
5. Pinnularia interrupta 
20 .... 
along each edge from centre 
.. top 26 '8 
19 .... 
.. bottom 25 • 5 
6. S. Phcenicenteron .. 
44 .... 
along axis 
44 .... 
41 .... 
along edge 
.. .. top 31-1 
7. Gramm, marina 
57 .... 
36-3 
8. P. Balticum .. 
48 .... 
near end 
32-9 
50 .... 
including middle 
34-3 
17 .... 
longitudinal 
31-5 
9. P. accumenata 
52 .... 
including middle along axis 
42-7 
10. Nitzschia amphoryx 
46 .... 
convex edge 42 • 9 
20 .... 
concave edge 45 ‘3 
11. P. angulata .. 
47 .... 
diagonal near centre (angles of diagonals 
58°) 
12. G. subtil. 
58 .... 
80 .... 
13. Surirella gemma 
51 .... 
at axis from centre 
54-8 
48 .... 
at edge 
37 .... 
longitudinal 
14. Nitzschia sigmoidea 
63 .... 
including middle 
63-0 
64 .... 
» .... 
64 .... 
63*2 
15. P. fasciola 
46 .... 
42 .... 
40 .... 
16. Surirella gemma 
16 .... 
near middle of length 
64-2 
20 .... 
)J .... 
20 .... 
24 .... 
almost half-way from middle to end .. 67 '3 
19 .... 
nearer to end than middle .. 
70-4 
17. Gym. elliptica 
35 .... 
along edge from centre 
63-3 
31 .... 
(probably was 30 — doubtful) 
65-1? 
18. Navicula crassinervis 47 .... 
24 .... 
81-1 
37 .... 
19. Nitzschia curvula .. 
50 .... 
? 
(counted number not given J. E. S.) .. 84’ 5 
20. Amph. pellucida 
42 .... 
counted three times . . 
43 .... 
?? v • • 
