32 DR. J. D. HOOKER ON THE GENERA AND SPECIES 



the embryo, which is pale, transparent, and formed of minute cohering cells, and 

 is not oleaginous. The apex of the stigma is obscurely 3-lobed : there is no very 

 distinct stigmatic canal ; but the cells of the stigma and centre of the style are soft and 

 pulpy. 



Griffith, who did not detect the embryo of this plant, considered that this albumen 

 (which he describes doubtfully as an embryo) suggests a greater resemblance to a sporu- 

 liferous mass than is sho^Ti by any other so-caUed Rhizanth : it is remarkable that this 

 observation should refer to one of the only three kno^vn plants of the Order, of which the 

 truly albimiiuous nature of the great mass of the seed is indisputable ; and is an example 

 of the inexpediency of assuming an organ to be anomalous because its structure is 

 imcxplained. 



The iafiorescence of Ilystropetalou differs from that of other Balanopliorece in the male 

 tiowers being at the summit of the capitulum, and the female below. In the monoecious 

 Cynomorium and most monoecious Helosidece they are promiscuously mixed, with the 

 males generally lowest; in monoecious Balanopliorece the males are nor*mally at the 

 Ijottom of the capitulum ; though I have seen traces of male flowers at the apex of a 

 capitulimi of B. involucrata. 



Mystropetalon is certainly ia all respects the most highly developed genus of the Order, 

 both from the complexity of the floral envelopes, and from the presence of a perfect embryo, 

 jdaced in the usual position of that organ in Phajnogamous plants. It was referred to 

 Balanophorem by Harvey and by Mr. Brown (Linn. Soc. Trans, xix. p. 233, in note*) ; and 

 though very anomalous in its greater perfection, must remain as a section of that Order, 

 or in close proximity to it. Griffith considered it as sui ord'mis, but with great sagacity 

 indicates its affinity with Cynomorium (a plant he had not examined), and finally described 

 it (doubtfully) as the homogeneous-embryo form of a group of plants including Lora/n- 

 fhacece, Froteacew, Santalacece, and other Orders comprehended in Lindley's alliance 

 Tuhiferosce. Considering the very great structural and morphological differences pre- 

 sented by Balanophorem, it becomes impossible to exclude Ilystropetalon from the Order ; 

 of its affinity with which there are many positive evidences, and the curious negative one 

 of extreme dissimilarity between the perianths of the sexes. Of positive characters, 

 the most conspicuous besides habit, are, ui the male flowers, the valvate 3 -partite 

 perianth, tubular below, and enclosing a rudimentary ovarium, the stamens opposite the 

 segments of the perianth, and the extrorse anthers ; in the female flowers, the epigynous 

 monosepalous perianth, the deciduous style, the structm-e of the waUs of the ovary, the 

 extreme simplicity of the ovule, and the adherent membranous coat of the seed. It 

 departs from all the rest of the Order in its male flowers being normally above the female ; 

 in its very unequal male perianth, its frequently imperfect odd stamen, and angular pollen ; 

 in the ovarian disc, deciduous perfect female perianth, 3-lobed stigma, presence of an im- 

 perfect pistil in the male flower, and axile clavate embryo. Considering its monostylous 

 ovary, with a tubular perianth, its nearest ally would appear to be Langsdorffia, between 

 which and Cynomorium it will rank in a linear series. 



* The species there referred to does not appear to me to be specifically distinct from M. Thomii. 



