摘要:

The variation shown by 60 characters (morphological, anatomical, embryological, chemical and cytological) is tabulated for the whole of the Ericaceae. The reliability of the characters and the observations on them are discussed, and it is emphasized that many characters are difficult to use because they are rarely restricted to one taxon. Six subfamilies are recognized. Within the Rhododendroideae seven tribes are recognized, the monogeneric Daboecieae being new;Epigaeais transferred to the Rhododendroideae from the Andromedeae andDiplarchefrom the Diapensiaceae.Callunais placed in a new monotypic tribe within the Ericoideae. The extended Vaccinioideae includes the Arbutoideae; five tribes are recognized, of which the Enkiantheae and Cassiopeae are new. The Pyroloideae and Monotropoideae are left unchanged: a new subfamily, the Wittsteinioideae, includes the deviant monotypic genusWittsteinia.A key to subfamilies, and to genera of the Pyroloideae, Rhododendroideae and superior‐ovaried Vaccinioideae is give

ISSN:0024-4074    

DOI:10.1111/j.1095-8339.1971.tb02133.x

出版商:Blackwell Publishing Ltd    

年代:1971

数据来源: WILEY

ISSN:0024-4074    

DOI:10.1111/j.1095-8339.1971.tb02134.x

出版商:Blackwell Publishing Ltd    

年代:1971

数据来源: WILEY

摘要:

Nectar secretion by grasses is rare.Andropogon gayanusvar.bisquamulatushas been observed to secrete nectar from two localized areas: (a) near the sheath margin immediately below the pseudopetiole; (b) the pseudopetiolar ridges adjacent to the ligule. Microchemical tests with Fehlings solution revealed high concentrations of reducing sugars at these two sites. Some evidence is given for supposing that the macrohair basal cells may secrete the nectar.

ISSN:0024-4074    

DOI:10.1111/j.1095-8339.1971.tb02135.x

出版商:Blackwell Publishing Ltd    

年代:1971

数据来源: WILEY

摘要:

A hybrid swarm between the hummingbird‐pollinated Jamaican endemicsColumnea urbaniiStearn andC. rutilansSwartz(Gesneriaceae)is described in terms of morphological, chemical and cytological characters.The importance of man‐made ecological niches to the establishment of hybrids is outlined and contrasted with the paucity of niches in undisturbedColumneahabitats. Niche availability determines the effectiveness of dissemination of both hybrid and pure seed.With the variation pattern of the Jamaican hybrids in mind, the possibility of hybridization between columneas elsewhere should be considered in systematic assessment of difficult groups in the ge

ISSN:0024-4074    

DOI:10.1111/j.1095-8339.1971.tb02136.x

出版商:Blackwell Publishing Ltd    

年代:1971

数据来源: WILEY

摘要:

The occurrence ofTolypella(Characeae) in Libya is recorded for the first time. Also for the first time, the structural development of the male and female fructifications (the globule (antheridium) and the nucule (oogonium) respectively) inTolypella nidifca(O. Müll.) A.Br. is described. Both the globule and the nucule show the same course of development as is seen inChara.In the final structure of the globule, however, there are two stalk cells inTolypella, while only a single cell is present inChavaandNitella.The corona has ten cells in two tiers of five each, as inNitella, but inCharathere is only a single tier of five cells forming the corona

ISSN:0024-4074    

DOI:10.1111/j.1095-8339.1971.tb02137.x

出版商:Blackwell Publishing Ltd    

年代:1971

数据来源: WILEY

ISSN:0024-4074    

DOI:10.1111/j.1095-8339.1971.tb02133a.x

出版商:Blackwell Publishing Ltd    

年代:1971

数据来源: WILEY