MR. W. GRIFFITH ON THE GENUS GNETUM. 307 
says, after alluding to his want of success in tracing the particles contained in pollen- 
grains through the tissue of the style, “ Even in those families in which I have sup- 
posed the ovulum to be naked, namely Cycadeæ and Coniferæ, I am inclined to think 
that the direct action of these particles, or of the pollen containing them, is exerted 
rather on the orifice of the proper membrane than on the apex of the included nucleus; 
—an opinion which is in part founded on the partial withering confined to one side of 
the orifice of that membrane in the Larch,—an appearance which I have remarked for 
several years.” It is, however, most probable that, from the late rapid increase of our 
knowledge of the process of fecundation in Phænogamous plants, chiefly indeed owing to 
the beautiful observations of this distinguished botanist, the opinion above cited has been 
modified by its author. 
With regard to the two principal objections urged by Dr. Brown * against the opinion 
of the female flower of Cycadeæ and Conifere being a naked pistillum, the first, viz. that 
arising “from the perforation of the pistillum, and the exposure of that point of the 
ovulum where the embryo is formed to the direct action of the pollen,” still holds good. 
The second, viz. the too great simplicity of structure of the supposed ovulum, I look 
upon as in a great measure destroyed by the reduction of the usual number of the 
constituent parts of this organ in Loranthacee}. 
Respecting the male flower, I have to add, that Linnæus was correct in referring the 
genus to Monæcia Monadelphia. Roxburgh adopts the same view in his MS. Synopsis ; 
but in his ‘Flora Indica’ he refers it to the Monæcia Monandria. The correctness of 
Linnzeus’s view is proved by the fact that there are two filaments at an early period, or at 
least that their union is only partial, and by the number, situation, and distribution of 
the vascular fascicles. 
GNETACEE, Lindley, in Bot. Register, vol. vii. N. S. t. 1686, sub Garrya. 
DraGnosis.— Plante gymnospermæ, dicotyledoneæ, aquosæ. Rami articulati. Folia op} ; 
venis anastomosantibus reticulata. iis ie d 
CHAR. gssENTIALIS.—Flores mohoici, in spicis amentiformibus verticillatim dispositi ; qum = 
lus involucro annulato integerrimo (rarius obsoleto) suffultus distans. MASCULI pluriseriati, in Mrd 
cillis inferius dispositi. Perianthium tubulosum, inverse subulato-conicum — a 
pressione angulatum, apice planiusculo vel depresso, rimá transverså | erg ses thesi ; 
mentum unicum, monadelphum (e 2 nempe coalitis formatum), hypogynum, , gere T 
per rimam transversam exsertum. Anther@ duæ, uniloculares, — E Mara a ple b 
nino discreti longitudinaliter et centraliter secus latus utrumque — ; m red 
oblongum.—Fæmrnan in verticillis superius dispositi, 1- niat deis pos ea E ix. 
ovata, sepe obliqua, transverse sita, orthotropa. (Junius.) Tegum — A ]lulosus å 
losum, interius cellulosum, sæpius inclusum, utrumque T apertum. Nucleus = a a 
mento conformis, liber. (Maturius.) Tegumenta terna; tertium T oda » e 
ejus apicem in tubum cylindricum styliformem longe exsertum ore ma pac ec us, 
niatis productum. Fructus (semen maturum) omnino exsertus, oo ve à le ig Auge 
lævis vel lepidotus, ovatus, indehiscens. Sarcocarpium extus cellulosum, intu 
i ium fibrosum 
utrinque acutæ pungentes, diametro magno, coloratæ), apice caper vcre = 
fragile, subosseum, sarcocarpio admatum, e fibris longitudinaliter cellulisque 
| my Paper on this subject. 
* * Kingid, p. 28. + See my Pape ds 
