242 



JVA TURE 



\yuly 14, 1887 



greatest service in every physical laboratory, and to be a 

 fitting companion to that already so well known. It is 

 to be hoped that the remaining volume, on light, heat, 

 and sound, will soon be ready. 



THE ROYAL BOTANIC GARDEN, CALCUTTA. 



Annals of the Royal Botanic Garden, Calcutta. Vol. I. 

 The Species of Ficus of the Indo-Malayan and Chinese 

 Countries ; Part I. Palasomorphe and Urostigma. 

 By George King, M.B., F.L.S., &c., Superintendent of 

 the Royal Botanic Garden, Calcutta. (London : Reeve 

 and Co., 1887.) 



DR. KINGdeserves well of botanists for his protracted, 

 though evidently profitable, labours on so varied 

 and difficult a genus as Ficus. From obvious causes, a 

 large proportion of the large arboreous tropical genera of 

 plants are still very imperfectly known, and, prominent 

 among them, Ficus; therefore Dr. King could hardly 

 have extended his researches in a more useful direction. 

 The present publication, which, from its general title, we 

 may assume will not be limited to a monograph of the 

 Asiatic species oi Ficus, is a tall quarto of sufficient size 

 to illustrate adequately almost all the species of the 

 genus in question. Indeed, this monograph possesses a 

 quite special value, inasmuch as every species is carefully 

 figured in natural size, with enlarged analyses of the floral 

 structure. 



Most persons interested in such matters will be familiar 

 with Fritz Miiller and Solms Laubach's investigations of 

 the sexual conditions in the flowers of various species of 

 Ficus, and the singular phenomena attendant on the 

 fertilization of the ovules. Nevertheless, it may be con- 

 venient to give here a brief account of the process.^ The 

 edible fig, which may be given as an example of the fruit 

 of the genus generally, consists of a thick hollow recep- 

 tacle, the inner surface of which is thickly studded with 

 flowers ; and, in the edible fig, exclusively with female 

 flowers. Male flowers of this species of fig are borne on 

 different plants, called the caprifig ; and associated with 

 these male flowers in the same receptacles are numerous 

 female flowers, occupying the greater part of the space. 

 Invariably these female flowers are infested by gall-pro- 

 ducing insects, hence they are termed gall-flowers, and 

 very rarely indeed is a single ripe seed found in a recep- 

 tacle of the caprifig. The insects hatched and nourished 

 in the gall-flowers leave the receptacles of the caprifig at a 

 period when the pollen of the male flowers is being shed, 

 and in making their exit bear some of it with them to 

 the receptacles of the edible fig, which they next visit ; 

 but they are unable to deposit their eggs in the perfect 

 females, and only serve to convey pollen to them. On 

 similar mutual adaptations the fertilization of all the 

 species of Ficus seems to depend. 



In an introduction to the descriptive part of his work, 

 Dr. King details the results of his own examination of 

 several hundred species, extending over some nine years ; 

 and he states that Solms-Laubach anticipated him only 

 in his explanation of the true nature of the " gall-flowers," 

 for he had found them in every species of the genus that 

 had come under his notice. He also enters into some 

 further particulars concerning the insects acting in the 



* Further details will be found in Nature, vol. xxvii. p. 584. 



process of fertilization, though he adds nothing more 

 conclusive. While admitting, and even assuming, that 

 the pollen of the males must be conveyed by the insects 

 developed in the gall-flowers "to the perfect females 

 imprisoned in the neighbouring receptacles," he is still 

 puzzled as to the way in which it is done.. We are under 

 the impression that Solms-Laubach indicates, if he does 

 not actually state in so many words, that he had not only 

 frequently seen the winged female insect issuing from 

 the receptacles of the caprifig, but that he had likewise 

 occasionally observed them enter the receptacles of the 

 cultivated fig, which is the female of the same species. 



This, the first part of King's monograph, contains 

 descriptions and figures of seventy-six species of Ficus, 

 whereof ten belong to his section Palceomorphe, and the 

 rest to Urostigma, which was originally proposed as an 

 independent genus by Gasparrini, and provisionally re- 

 tained as such by MiqueL King found five different 

 kinds of flower, variously associated or removed, in the 

 Asiatic species of fig ; and upon characters derived from 

 the differentiation and arrangement of the sexual organs 

 he classifies the species in two primary groups and 

 seven sections. The species of the relatively small 

 group Palceomorphe are distinguishable from all the 

 others by having spuriously bisexual flowers associated 

 with gall-flowers, while the fertile females occupy separate 

 receptacles. In the definitions of the sections, the pistil 

 in the functionally male flowers is described as rudi- 

 mentary, though perhaps sterile would be a better term 

 to use, because, as figured, and designated in the explana- 

 tions of the figures, it is a fully-developed gall-pistil. 

 This condition is regarded as the nearest approach to 

 assumed original complete hermaphroditism. 



In all six sections of the larger group the sexes are 

 strictly separated, as to the individual flowers ; and in the 

 section Urostigma, male, gall, and perfect female flowers 

 are intermingled in the same receptacles. We have over- 

 looked it if there is any explanation of the advantage 

 derivable from the presence of gall-flowers where both 

 sexes are also found in the same receptacle ; but it may, 

 perhaps, be found in the fact that the inflorescence is 

 proterogynous or proterandrous, hence insect agency is as 

 necessary as in those species where the sexes are in 

 diff"erent receptacles. 



In the remaining five sections the male and gall-flowers 

 are invariably borne in one set of receptacles, and the 

 fertile female flowers in another set ; and the presence of 

 neuter flowers in the female receptacles characterizes the 

 section Synoecia. The neuter flowers contain rudiments 

 of neither sex, which condition King explains by saying 

 the neuter flowers are asexual. 



Neuter flowers are wanting in the sections Sycidium, 

 Covellia, Eusyce, and Neomorphe ; but the arrangement 

 of the flowers is otherwise the same as in Syna;cia. The 

 two first of these sections have monandrous male flowers, 

 and the two last have diandrous or triandrous male 

 flowers : while the receptacles of the first and [third are 

 mostly axillary, those of the second and fourth are usually 

 borne in fascicles on the stem and branches. Thus it 

 will be perceived that the distinctive characters of these 

 four sections are somewhat artificial. However, it is 

 only fair to say that the author himself points out this 

 fact. 



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