184 
WILLIS: PODOSTBMACBÆ 
subsequently added several from Ceylon ; his paper^ contains 
descriptions of Tristicha ceylanica, the first of this genus to 
be discovered, and of Podostemon Griffithii, Wallichii, oliva- 
ceum, griseum, subulatum, dichotomum, Wightii, rigidum, 
and elongatum, together with an interesting account of the 
order, some species of which he had also studied in Brazil. 
The next to occupy himself with this order was Law, who 
during his residence at Thana, near Bombay, made excur- 
sions into the Ghats lying to the eastward. Numerous little 
streams flow westward down these hills, uniting to flow 
out near Salset Island. In the floras, Law’s localities are 
often given as ‘‘ Salset River.” I am indebted to the 
Collector of Thana for pointing out that no such river exists, 
and that probably Salset Rivers ” is meant, including all 
the little streams just mentioned. As much doubt has arisen 
over Law’s specimens and their localities, I quote here all that 
I was able to find in his correspondence with Sir William 
Hooker (preserved at Kew) bearing upon this subject • 
No. 300. Tanna, 30th October, 1844 : “ The genus Hydro- 
bryum founded by Endlicherf on some species of Podoste^ 
mon described by Dr, Griffith in the Asiatic Researches is 
considered by the latter botanist to be untenable, in which 
Robert Brown agrees with him. The plant of which I sent 
you a specimen is however a new and very distinct species 
of Podostemon, which Dr. Griffith proposes to name P. 
ecostatum,J the fruit not being ribbed as in the other species, 
I enclose a few more specimens in fruit, and probably by 
next mail may be able to send you some in different stages, 
I have discovered another Podostemmea, which Dr. Griffith 
considers to be the type of a new genus, to be characterized 
in a paper on the Indian Podostemmeæ. At Dr, Wight’s 
suggestion he proposes to do me the honour to name it after 
me. Of this also I enclose a few specimens.” 
* Observations on the Structure and Affinities of the Plants belong-ing- 
to the Natural Order Podostemaceæ. Calc. Journ, Nat. Hist. VII., 1846. 
t Endlicher, Genera Plantarnm, p. 268. 
X P. Hookerianus, Benth. 
