!-;jri, at the hutt So far as we cau tell the treed flower in December awl 

 January, but fairly vecH-dcvelopcot buds have been collected at ^11 seasons. 

 Fruits, of rourse, are available over a considerable penod- 



*The only oiher species in the Condnholin district which would lie liVceK 

 to hybridise with Rivcj Red Gum 15 /;. dt&Hfata (and related forms). How- 

 ever, these are sjtert-jitd&i'lfod forms And hybrids with River .Red Gum 

 wotdd nut resemWc the lorty-pediceJJed type spetinieii <y( & i&Hwtdulth&s ' 



Mr- Anderson also writes ; "From the photograph it appeal's to ur- that 

 tlie buds of the type are markedly immature The sha|»e oi the operculum 

 dm-i riot really seem so very different from fairly normal River Red Gum at 

 certain immature stage*" 



We add'' further: "I feel, however, (hat it US. taniaMulcitsi?) 15 "best 

 reiitned as the name for the Kivev Red Gun* unless u can he shown thai 

 the type does not fall within the ambit of that fperick Whether the type ia 

 leprescutaiive of ibe mas' usual form t> ivomeiiclatonally irrelevant 



Nearly all the RireT Red Gums in regions accessible hcJore 1822 have 

 markedly lOslratc buds. These buds, in the neighbourhood of Adelaide, for 

 instance, take a long lime to mature. Next season's rostrate hiids may be seen 

 soon After the link of fioweriog. What « the sigipfteaUKe of meeting with 

 occasional tree* in which all the buds show practically 110 rustratiort, whiKi 

 all olheis »ti the neighbourhood are rostrate? 



Proie>Jor D. G. Caichoudc has kindly sullied The fdllowfeltf paragraph 

 ''The irituatr-jn parallels in a striking way die clnu\ variation seen m species 

 which have been subjected to expeninenlal analysis ( floiihtgo woritwm Sort 

 A*\illea nttUiiohtitn) h is accounted for by the different yeno frequencies 

 in different poptilatioiu* showing a fairly regular trend in relation to yeo- 

 graphical distribution Unknown factor* of natural Lr3$ctlf>n have brought 

 about this regularity, which might be correlated wi4lt depree of aridity." 



As we proceed north in South Australia, the sucker leaves tend to become 

 broader and more glaucous I tin* appears even in the northern Flinders 

 Ranges.) aiM the oud> tof* their rostra** appearance- Specimens I recently 

 collected (IS54> in the Musyravc Ranges and on the Officer arc broadly 

 Inn shortly conical. The same appearances are found ill the MacDcnncil 

 Kjopc*. 



AnolheT factor of interest is thai many of* the River Red Gums must be 

 \try old. some probably a thousand years old. EfVorii are UetOg made to 

 ascertain the age by taking wood from the intact centre oi very large trees 

 and seeing what i? the relation of CI4 to C12- If fl young Kiver Red Gum 

 can .-set seed in ten years, it nuyltt aive rise tr> ten generation*.; in a hundred 

 vears 01 '00 in a thousand years, 1 suppose nothing unusual would haj/pcii 

 if pollen liom such a young tree, 100 generations removed from a neighbour, 

 fertilised the latter After all. the River Ked Gum on the Yarra must have 

 been vcmpletcTy separated from those round Adelaide for many thousands 

 ot year*, yei no difference can be detected 



To sum up. where does this lead us? I£. carfHiftluU'Hsis probably came from 

 the Lachtaii. It is imlil&c the common southern River Red Cum in not being 

 rostrate. Jt is cither a mutant ur a hybrid of the River Red Gum. Can a 

 minor rmu;oSon he sufficient to establish a variety? If $0, Hie common 

 southern River R&J Gum initfht be called /:. en nut hinh' n.-nV var. {cn*)tro£tris. 

 Rut this perhaps wtvuld he carrying things io an eMretne ft )- ob\ious, 

 however, that it is a pity the name was. ever revived, <incc there, n a 

 pOisioiliTv That ii is n bylind, ft wi:tdtl be uitcrcshni* to knuw ivhether a»y 

 of its progeny survived and what thev were like. 



/IJtUti tilth;,— Professor Calcheside. *k.s, ha* %\v&\ me permission to 

 iikcludc tlic fullowiitg elaboration of the paragraph by him included in the 

 tcxl: 



"It is common experience that when a widely, or even narrowly, ranftni^ 

 ajiteies is analysed eeiieucally it is ii>mu\ to show very considerable genetic 

 diversity. In particular, if the frequencies of allelic £eiics arc determined. 



