464 MR. C. REID ON LIMNOCARPUS, 
named C. alpicola, Wahl., grew in an equally elevated situation. 
This dispelled the thought that had been in my mind that 
C. helvola was only a sterile form of C. canescens caused by 
growing at so great an altitude. I hope the specimen which 
Mr. B. S. Ogle is cultivating for me may, when mature, throw 
some additional light upon the subject. 
In conclusion I may say that in 1896 I made an unsuccessful 
search for C. helvola on Loch-na-gar, but I had so little time 
at my disposal that I was unable to examine the southern slope, 
where in the eighties I remember seeing mountain forms of 
C. canescens. Pfarrer Kükenthal has recently seen our C. helvola 
and considers it to be canescens x lagopina. 
On Limnocarpus, a new Genus of Fossil Plants from A 
Tertiary Deposits of Hampshire. By CLEMENT Re 
F.L.S., F.G.S.* 
| Read 17th March, 1898.] 
WuILE engaged on the Geological Survey of Hampshire 
during the last ten years, I have found abundance of a fruit 
closely allied to Potamogeton and to Ruppia, though differing 
materially from those genera. As no generic description 
appears to have been published, and this seems to be one of the 
rare cases in which a Tertiary plant can be shown to belong 
to a generic type now extinct, I have delayed publishing the 
new genus until further material eould be obtained and some 
doubtful points could be eleared up. 
No description can yet be given of any part of the - 
except the fruit, though the type species seems to have im 
linear leaves like those of Ruppia or of many species P 
Potamogeton. Leaves of this character occur in certain seams 9 
loam in the Lower Headon Beds containing no fruits except 
those of Limnocarpus. 
LiwNocamPUs, genus novum e Naiadacearum. — pus 
Fructus succulentus ? Carpella 2, pedicellata, sese margini 
ventralibus adherentia: endocarpium durum, a tergo ros 
admodum foveatum, rugosum: rostrum productum. Sem 
circa loculi processum curvatum, testa coriacea. 
Species unica, herbze aquatice. . t 
Accedit Potamogetono sed ab eo carpellis 2 nec 4 discrepat. 
* By permission of the Director-General of the Geological Survey. 
