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Chromosome Numbers of Spermatophytes, Mostly Californian

1965; California Botanic Garden; Volume: 6; Issue: 1 Linguagem: Inglês

10.5642/aliso.19650601.08

2327-2929

Peter H. Raven, Donald W. Kyhos, Albert Hill,

Sperm and Testicular Function

Studies of chromosomes are normally confined to limited taxonomic groups, for very good reasons.Studies thus restricted are not only apt to yield more accurate results than those concerned with a wide variety of plants, but the patterns within these groups may become obvious with relatively little effort.One unfortunate effect of this kind of orientation, however, has been that many groups of plants have never or very rarely been examined cytologically, and many interesting facts thus remain unknown.The superb living collections of California plants at the Rancho Santa Ana Botanic Garden have provided the nucleus of this study.Each is associated with a voucher collected in the field at the time of the original collection.These have been supplemented by selected collections of wild plants, mostly from California and adjacent areas.In general, meiotic material has been fixed in one of the variants of Carnoy's solution and squashed in acetocarmine.Observations of meiosis in pollen mother cells have provided the bulk of the information on chromosome numbers presented here.Occasionally, we have obtained chromosome numbers from mitotic divisions, either in floral material or in root-tips.The present study reports chromosome numbers for 144 collections of 121 taxa.Included are what we believe to be the first reports for Pectocarya, Oxystylis, ldahoa, Acanthomintha, Pogogyne, Salazaria, Pickeringia, Adensostoma, Cneoridium, Anemopsis, Galvesia, Mohavea and Plectritis.Also included are first counts for 79 species and 8 additional subspecies and varieties, including such prominent members of the California flora as Epipactis gigantea, Toxicodendron diversilobum, Sambucus mexicana, Cercidium flordium, Salix lasiolepis, Platanus racemosa, Staphylea bolanderi, and Styrax officinalis.Our counts for Cleome lutea, C. serrulata, Fouquieria splendens, Lyonothamnus, Simmondsia and Psoralea macrostachya differ from previous reports, which in all except perhaps the second and fifth cases we believe to have been approximations only or in error.Our earlier report for Erysimum capitatum subsp.bealianum is shown to have been in error.We believe that the present article includes the first accurate report of a chromosome number in the family Fouquieriaceae.Additional comments are found under the species concerned,