TRANSACTIONS OF MICROSCOPICAL SOCIETY. 
DESCRIPTION OF PLATES VIII & IX, 
Illustrating Dr. Greville's paper on New Diatoms. 
Series XVII. 
Fig. 
1 . — Cladogramma co7iiciim . 
2. — „ ,, front view, 
3. — Thaiimatonema costatum, 
4. — Siiciodiscus Hardmanianus. 
5. — Hemiaulus minutus. 
6 . — Lira discus ellipticus. 
7. — Biddulphia decorata. 
8. — Heihergia Barhadensis^ frustule, 
9. — 55 „ lateral valve, 
10. — Asterolampra exim'ia. 
11. — Bicladia rohusta. 
12. — Hemiaulus crenatus. 
13. — Porpeia quadriceps F 
14. — Tricerutiuni polygonium . 
15. — „ figuratim. 
16. — 5, quadricorne. 
17. — „ zonatulatum, 
18. — „ inglorium. 
19. — „ quadraUm. 
20. — 5, latum. 
21. — reticulatum. 
22. — „ parallelwn^ 4-angled valve. 
23. — „ „ 6-angled valve. 
24. — sexangulalum. 
25. — „ implicitum. 
26. — jj brevinervum. 
2 7. — AmpJdtetras nobilis. 
All the figures are X 400 diameters, 
