HOMOLOGIES OF ORCHID FLOWERS. 33 



HOMOLOGIES OF ORCHID FLOWEES. 



1'he peiusal of the foregoing outlines of the morphology of 

 orchid flowers may seem somewhat tedious to many readers, and in that 

 case, the following details of their homologies will doubtless seem 

 not less so^ but those who desire to comprehend the marvellous 

 structure of orchid flowers and the wonderful contrivances that are to 

 be found in them to secure the end for which they have been 

 created^ will not only find the attention required not excessive, but 

 also that when the subject is once fairly grasped, the perusal 

 combined with the examination of fresh specimens will result in 

 pleasure far exceeding that aflbrded by a cursory view of the 

 most gorgeous or most striking of many remarkable productions 

 in this strange family of plants. 



It has already been remarked that notwithstanding the apparently 

 endless and irreconcileable variety of form into which orchid flowers 

 have developed, a general plan of floral structure pervades the ivhole 

 family ; this general plan must have had its foundation in some more 

 primitive form than is at present known, and from it all the numerous 

 existing forms are supposed to have been derived. The making out 

 of the structure of this ancestral form or ideal type as it is some- 

 times called, has exercised the sagacity of many botanists, but the 

 merit of clearly unfolding the homologies of orchid flowers and of 

 interpreting rightly the meaning and functions of the various parts, 

 especially of those that are only now seen in a rudimentary 

 condition, is mainly due to our own distinguished countrymen 

 Dr. Robert Brown* and Mr. Charles Darwin. f To the last-named 

 naturalist we owe the lucid explanation of them in his classical 

 work on the Fertilisation of Orchids, and from the chapter especially 

 devoted to the homologies of orchid flowers, the following account 

 of them has been solely derived. We could have wished to have 

 given the eminent naturalist's elucidation of these homologies in 

 extenso, but as many details are adduced which our space precludes 



* Observations on the Organs and Modes of Fecundation in Orchidca', 1831, one of the 

 most inijiortant papers ever read before the Linnean Society. 



t On the A'^arions Contrivances by which British and Foreign Orcliids are fertilised by 

 insects (John Murray, 1862), a work tliat should be read and re-read by ever}' amateur of 

 orchids. 



