230 Bower. — Imperfect Sporangia in certain 
7. L. Saururus, Lam. There is usually a sterile basal region of 
some length ; no obvious external distinction of sterile and fertile 
regions. 
9. L. Hamiltonii , Spreng. (inch L. vernicosum , H. & G.). Plants 
from Khasia (C. B. Clarke) show transition from sterile to fertile 
region very gradually as regards leaf-form ; at most there is a gradual 
and ultimate diminution of size. Occasional single sporangia may be 
found far down in the sterile region, in the axil of leaves of the larger 
sterile type. This has been seen in many other specimens besides 
Clarke’s Khasia plants. 
11. L. reflexum , Lam. As in L. Hamiltonii , isolated sporangia were 
found in the lower sterile region. 
12. L. miniatum , Spring. The same. 
13. L. ceylanicum , Spring. The same. 
14. L. lucidulum, , Michx. No distinction of sterile and fertile zones : 
sometimes the fertile zone is very short; in some cases a single 
isolated sporangium is found in a sterile zone. The external differ- 
entiation of sterile and fertile zones is feeble. 
16. L . s erratum, Thunb. The foliage leaves of this species are 
unusually large. The size of the sporophyll varies : it may be fully 
the size of the foliage leaf, or it may be a mere tooth, subtending the 
large sporangium : but there is no obvious balance between the size 
of the sporangium and that of the sporophyll. This all shows that 
the larger size of the leaf does not necessarily depend on its being 
sterile ; but usually the sporophylls are smaller than the foliage 
leaves, and this is specially the case at the upper limit of the fertile 
zones. 
17. L. fir mum, Mett. 
18. L. rigidum, Gmel. 
Group of L . taxifolium. 
20. L.fontinaloides, Spring. Alternating sterile and fertile zones 
without external differentiation, and of varying length. 
2 1 . L. tetragonum, H. & G. Usually sterile below, but after the 
transition, without change of form of shoot, the fertile form of shoot 
is maintained. 
22. L. myrsinites, Lam. Alternating sterile and fertile zones: 
isolated sporangia found here and there in the sterile region. 
