610 



OROBANCHACE^. 



[Perigynous Exogens. 



ripe. The gi'eat points of resemblance between Orobanche and Gesnei'worts and Figwoi'ts 

 consist in their monopetalous didynamous flowers and bicarpellary polyspermous fruit ; 

 and it is these which have led to the general opuiion that all the Orders are closely 

 allied. Such marks of agreement are doubtless important ; but they may be over- 

 balanced by circmnstances of disagi'eement of more importance. One of these is the 

 position of the carpels with respect to the axis of inflorescence. In the whole category 

 of personate, labiate, or irregular plants forming the Bignonial Alliance, the carpels 

 stand fore and aft with respect to the axis ; while in Gentianworts we have as univer- 

 sally the two carpels placed laterally. In this striking character Orobanche agrees 

 with the latter. Now as a didynamous stinicture is not universal in Bignonials, while 

 the position of carpels is constant tlu'ough both series respectively, we must assign the 

 greater importance to the latter character, and hence Orobanche would be removed 

 from Bignonials to the series represented by Gentians ; of which this genus would be a 

 didynamous form, analogous to what frequently occvn-s among Bignonials. If to this 

 we add the resemblance between Broomrapes and Gentians in the minuteness of their 

 embryo as compared with the albumen, no doubt can, I think, remain as to the very 

 near alliance between the two. 



The peculiar placentation of this Order was mentioned by me some years ago, 

 (Tayloi'^s 3Iagazine,l!^ov. 1837). That their capsule consists of two carpels standmg 

 right and left of the axis of inflorescence, and with the margins not inflected in the 

 form of dissepiments, is incontestable. Yet in Oro- 

 banche and Phelypsea the capsule has four placentae, 1 

 placed equidistant in pau's upon the face of each valve or 

 cai'pel, and considerably ^^'ithin the margin. In Epiphegus 

 each carpel has two intramargiual placentae, which diverge 

 from the base upwards, and terminate before reaching 

 the apex. In Lathreea there is to each valve but one 

 placenta, which may be regarded as two confluent ones 

 occupying the very face of the dorsal suture of the 

 carpel. And finally in iEginetia indica, and I beheve in 

 -^ginetia abbreviata also, the placenta is in like maimer 

 confined to the axis of the valve, occupying the same 

 position upon the carpels as in Lathrsea, but broken up 

 into a number of parallel plates of unequal depth, over 

 the whole surface of which multitudes of minute seeds 

 are distributed. 



According to the observations of Vaucher, of Geneva, the seeds of Orobanche 

 ramosa will lie many years inert in the soil unless they come in contact A^ith the roots 

 of Hemp, the plant upon which that species grows parasitically : when they immediately 

 sprout. The manner in which the seeds of Orobanche attach themselves to the plants 

 on which they grow has been observed by Sclilauter. This writer states that they only 

 seize seedhngs, and are unable to attack roots of a stronger growth. When Picris 

 hieracioides is attacked, he found that the Orobanche seeds seize upon the points of the 

 roots exclusively ; the latter then swell and form an enlargement which serves for a 

 base to the Orohetnche.-^Ann. Sc. n. s. 10. 318. Duchartre has studied with great 

 diligence the development of Clandestina, in whose stem he finds neither medullary 

 sheath nor medullary processes ; and according to Messrs. de Mirbel, Richard, and 

 Ad. Bronguiart, the same remarkable sti'ucture occm's among Figworts in the case of 

 ISIelampyrum sylvaticum. — Ann. Sc. N. n. s. xx. 145. 



Broomrapes are not uncommon in Europe, particularly in the southern kingdoms, 

 Barbary, the Cape of Good Hope, middle and northern Asia, and North America ; they 

 are very rare in India. 



Orobanche major is a powerful, astringent, bitter plant, the infusion of which has 

 been employed as a detergent application to foul sores, and internally to resti'ani alvine 

 fluxes. Epiphegus virginiana is supposed to have foi-med, in conjunction with wliite 

 oxide of arsenic, a famous cancer powder, which was known in North America tmder 

 the name of Martin's Cancer Powder. It is thought to participate in the properties 

 of Orobanche major. Orobanche epithymum is an old-fashioned bitter tonic, and 

 "VTilnerary ; and its fragrant flowers are used in spasmodic aff'ections. Latlii'aea 

 Squamaria roots were given m epilepsy, and Clandestina was supposed to counteract 

 sterility in women : but these things are now forgotten, ^ginetia indica, prepared 

 with sugar and nutmeg, is considered an antiscorbutic. Phelipeea lutea dyes black the 

 ropes that are prepared from the fibres of the Doom Palm of Thebes. 



2 3 



Fig. CCCCXIII. 



Fig. CCCCXIII. — 1. seed and embryo of Conopholis americana ; 2. section of ovary of Epiphegus 

 americana ; 3. section of fruit of Hyobanche sanguinea. 



