304 



They will have been equally in force in the past, and must have had an influence on the phytogeny, and find 

 expression in at the present day less nearly allied species. Indeed, there is much reason for the conclusion 

 that the juvenile forms of the vegetative organs often point to relation of species apparently now very 

 distant. 



(p. 93). E. peltala Benth., is the first example. This species of an inland north-eastern district, 

 which occurs in the neighbourhood of the Burdekin, Lynd, and Gilbert Rivers, is the only species of the 

 genus which has peltate leaves in the full-grown state (Mueller's error again repeated, see Part XLII. p. 33. — ■ 

 J.H.M.). Otherwise it shows in many characters, especially in the very important shape of the fruit, a 

 great approach to E. laiifolia. It is more than probable that the two species are closely connected ; indeed, 

 in their geographical distribution they belong to the same region, i.e., north-east Australia. Unfortunately 

 the ontogeny of E. laiifolia is not perfectly known. I could nowhere find a description of the juvenile 

 leaves. Generally speaking, the peltate leaf in Eucalyptus is a character of juvenile form, which I saw in 

 surprising perfection in E. calophgUa and in E. erythrocorys. 



(p. 93). Eucalyptus cordata. Another case is given by Mueller under E. cordala. This Tasmaniau 

 species remains mostly shrubby. It belongs to the species with sessile, opposite, cordate, and orbicular 

 leaves with crenate margins, possessing therefore prominently the characters of juvenile leaves. Crenatu 

 leaves, says Mueller in " Eucalyptographia," occur also in E. umigera, and, strange as it may appear, 

 E. cordata is nearest allied to this species. In its full-grown state W. umigera has alternate, dark green, 

 lanceolate-falcate leaves on long petioles, the calyces are elongate and narrowed at the base into distinct 

 pedicels, the operculum is larger and the fruits are urn-shaped with sunk valves, but Mr. Stephens found 

 on '" Old Man's Head,'' a sub-alpine mountain near Lake Crescent, trees which formed, to all appearance, 

 a perfect transition between E. umigera and E. cordata. 



(p. 94). Further, Augustus Oldfield sent many years ago from Mount Wellington, near Hobart, 

 sterile specimens of the juvenile state of E. umigera, whose lower sucker-shoots could not be distinguished 

 in foliage in any way from E. cordata, and which had to some extent also the same whitish bloom. On 

 Mount Wellington I collected a state of E. umigera whose leaves were nearly oval and whose fruits were 

 " truncate-ovate." (The mature leaves of E. umigera are alternate, petiolate, and lanceolate. See fig. 15, 

 Plate 80.— J.H.M.). 



Then follow some notes on E. tetragona and its affinity to E. eudesmiokles, which 

 I have translated and quoted in Part XL VI, pp. 162 and 168. The affinity is explained 

 at the bottom of p. 168. 



We then pass on to Dr. Diels's " General Remarks concerning Eucalyptus," 



(p. 95). 



The cases described on page 89 (E. Risdoni and E. amygdalina) enlarge the validity of the previously 

 explained connection between juvenile forms and flowering maturity, but its limits are not yet reached. 

 We clear a way for it if we try again to lay down the characters of the primary state of the heteroblastic 

 Eucalypts. The following forms appear to be essentia.] , or, at least, specially common in the juvenile state, 



(p. 96). 1. Shape. Leaves opposite, connate in pairs or sessile or shortly petiolate, the blade often 

 cordate at the base, occasionally even the petiole is superbasal (peltate). 



2. Bloom. Frequently all parts have a whitish or glaucous waxy bloom. 



3. Hairs. Frequently the axis and leaves are covered with bristly hairs. 



We find that a series of species of Eucalyptus produce flowers in the vegetative juvenile state as well 

 as in the matured vegetative state, and therefore develop two generative identical parallel forms, as shown 

 on pages 90 and 91. In other cases, the existence of such pairs of identical species has been at least shown 

 as probable (pp. 93, 94). But there are still other states in Eucalyptus. There are normally flowering- 

 species with juvenile leaves, of which we have not yet found their doubles with mature foliage. I mention 

 three of the most prominent species of this kind. 



1. E. gamoplu/lla F.v.M. Leaves all opposite and broadly connate, often cordate, equal-sided, of 

 whitish-grey colour. An always shrubby species inhabiting the dry north-west quarter of Australia, and 

 extending from the Hammersley Ranges south-east to the upper Finke River. The relationship of this 

 species is doubtful, 



