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in tli. • _ 5; because both Lid and tube arc homogeneously confluent while in bud, and when their 

 severance takes place by force of extrusion of the stamens, we find the transverse line of separation not our 

 of clear dehiscence, l>ut one of more or less irregular tearing; nor does this rupture Lead always fcoa shedding 

 of the lid. it being often retained during the whole time of flowering, and thrown simply back from the 

 remaining place of alligation (attachment.) Nevertheless, the lid of Eucalyptus may in some instances be 

 regarded a^ externally calycine and internally petaline (coralline;) this view obtains complete confirmation 

 by the species now before us [eximia), and by a few other congeners. 



When the lid of E. eximia has been well macerated, a tender petaloid (corolloid) inner membrane 

 may readily be drawn off from tic thinly eartilagineous calycine portion of the lid; this inner stratum. 

 which in nature seems often to be set spontaneously free at last, as 1 found this to be the case with a lew 

 other congeners, produces from its centre a short descending tube, which encloses the summit of the style 

 and tie- Stigma before the flower expands. 



Such tubule descending from the inner lid is not to be found on the operculum of the closely allied 

 E. maculala, in which species the two opercular strata are also far less dissimilar than in E. eximia, thus 

 more conformous to the occasional two of E. rostrata and the regular two of E. peltata, not to speak of some 

 others; yet the inner may be regarded as petaline also in E. peltata; and we would perhaps be justified in 

 iming that the lid of Eucalyptus calyces is formed generally by the permanent confluence of an inner 

 petaloid and outer calvcoid layer. 



Additional light is shed on the structure of the lid of Euealypts and some other nivrtaeeous genera 

 by Pleurocalyptus, in which the operculum is retained on one side after the irregular transverse bursting of 

 the calyx, similarly to what occurs in Eucalyptus corymbosa and its allies: petals are, however, conspicuously 

 developed. But in Adoalyptus and Piliocalyx the petals, although distinctly formed, are of irregular and 

 diminutive size and even somewhat coherent or concrescent. whereby some transit to the petaloid inner 

 lid of some Euealypts is established, just as in a similar manner the petals of several species of Eugenic* 

 belonging to the section Acmena or Syzygium, become very much reduced in dimensions and also sometimes 

 connate. It is different with Angophora, which genus finds habitual repetitions in some Euealypts, for 

 instance. /:'. siiosn and E. axpera; here the calycine lobes assume the appearance of petals; but they are 

 sile with broad base, and only petaloid towards the margin, as to some extent in Leptospermum, Eugenia 

 and many other Myrtaeeous genera; while the five alternating points, continuous to the main ridges of 

 the calyx-tube, are equivalent to the calyx-teeth developed in E. tetraptera, and still more distinctly in 

 E. odontocalyx and E. tetrodonta, the lid of all being calycine also."' (" Eucalyptographia " under 

 E. eximia.) 



(4) " In E. Preissii, E. terminal/is, E. Abergiana, and a few other species, the calyx is rather 

 irregularly ruptured than circumcised by a clearly defined sutural line; at best only the inner layer of the 

 lid could be assumed to be corollaceous, but it is closely connate with the outer stratum as usual in the 

 genus." (ih. under E. tetrodonta.) 



(5) "A narrow and elongated outer quickly deciduous operculum covers not rarely the normal 

 lid." {ib. under E. rostrata.) 



Naudin, L891. (1) " The operculum, which is not. in my opinion, any different to the corolla of 

 which the pieces are fused congenitally, often furnishing good specific characters by their shape and 

 relative size." (Mem. ii. 13) (translation.) 



(2) " Then- are iii reality two superposed opercula, the exterior, attributed to the transformation 

 of the calyx, is reduced to a scarious skin, very fugacious, which caps the coralline operculum. One only 

 it in very young buds, for it falls early. It seldom develops as much as the interior operculum, which 

 then appears to be double.'' (//,.) 



Drw>r. I J !>7. " The flowers themselves have Inst lhe power of producing petals, except as such 

 may be represented m the deciduous operculum, and this gives a still stronger hint of the whole plant 

 having become modified in the course of lone ages to resist drought, whereas its closest congeners, 

 /. .'.//.../ ami Angophora, which have petals, are confined respectively entirely to the coast districts or to 



damper situations on the eastern side of Australia, not having 1 D able to penetrate very far into the 



droughty interior." (If. Deane, Proc. Linn. Soc. N.8.W., xxii. 171, 1897.) 



