Volume 2, No. 2, 1977

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(pp. 2-5)
Seed Photography - An Aid to Seed Identification1
R. J. Delorit2
ABSTRACT:
Photography, especially color photography, can be a valuable aid to seed identification. To produce useful photographs, the photographer must first know the unique characteristics of each species. Meticulous preparation of the sample is necessary to ensure that (a) the sample is representative of the species. (b) both dorsal and ventral sides are shown, and (c) all inert matter is removed from the seed and background. To highlight characteristics such as pubescence, tubercles, striations, etc., the intensity and direction of the lighting must be manipulated and proper background colors selected. Focus­ing and time of exposure are critical to high quality photographs and are learned only from experience.

Additional index words: color seed photography, seed identification.
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(pp. 6-23)
Pictures and Descriptions of Certain Seeds Not Illustrated in Agriculture Handbook 301
Elizabeth F. Wiseman, Stephen J. Hurst and Karen Faul2
ABSTRACT:
Certain seeds added to the Federal Seed Act since 1952 (Group 1) and others of interest to seed analysts (Group 2) are illustrated and described for identification purposes: namely, (Group 1) Atriplex canescens (Pursh) Nut­tall, Bromus biebenteinii Roem. & Schult., Crambe abyssinica Hockst. ex R. E. Fries, Cynodon dactylon var. aridus Harlan & de Wet, Phleum nodosum (L.) Huds., Poa glaucantha Gaudin, Trifolium vesiculosum Savi, X Triticosecale; (Group 2) Brachiaria platyphylla (Griseb.) Nash, Eragrostis curvula (Schrad.) Nees 'Renner,' Eragrostis plana Nees, Eragrostis tef (Zuccagni) Trotter, Leptochloa uninervia (Presl) Hitchc. & Chase, Puccinellia distans (L.) Parl., Ventenata dubia (Leers) Cosson.

Additional index words: spikelet, floret, caryopsis, pod, bract.
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(pp. 24-29)
Seed Coats Under the Scanning Electron Microscope1
Gerald A. Mulligan2
ABSTRACT:
Scanning Electron Microscope photographs of seed coats of Brassica and Sinapis species, at 500 magnifications, clearly show the characters of seed coats. Identical seed coats of various intraspecific entities within Brassica campestris (weed seed, rapeseed, turnip, Chinese cabbage and Tori) em­phasize the futility of trying to separate many intraspecific entities by means of seed coats characters.

However, the SEM photographs show the distinct differences present on the seed coats of Brassica campestris L., B. napus L., B. oleracea L., B. nigra (L.) Koch, B. juncea (L.) Czem., Sinapis alba L. and S. arvensis L. The amphidiploid B. napus (2n = 38, genome aacc) clearly com­bines the seed coat characters of its diploid ancestors B. oleracea (2n = 18, genome cc) and B. campetris (2n = 20, genome aa). Even more dramatical­ly, the amphidiploid B. juncea (2n = 36, genome aabb) combines the seed characters of the ancestral diploids B. campestris (2n = 20, genome aa) and B. nigra (2n = 16, genome bb).
Additional index words: Brassica spp., Sinapis spp.
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(pp. 30-39)
Mechanical Seed Identification1
Charles R . Gunn2
ABSTRACT:
A user-computer dialogue has been established at the U.S. National Seed Herbarium to identify isolated seeds and fruits. Four major data processing programs are used to make identifications or to solve taxonomic problems.

Properly prepared documentation sheets facilitate the recording and numeric coding of diagnostic seed-fruit characters. These coded characters are data banked as dichotomous, multistate, or quantitative observations. Because the manual completion of these documentation sheets may be quite time consum­ing, systems are being considered to automatically generate computer­ compatible data. Elements of   one system are the scanning electron microscope (SEM) and an optical scanner with a direct computer feed. SEM photographs could be optically scanned to determine seed shape, size, and surface topography as well as the relationships of the hilum, lens, and aril to seed shape and size. The computer is programmed to suggest useful characters for an identification, to recognize character and taxon weights, and to permit correction of user errors while an identification is in progress.
Additional Index Words: Computer, data bank, documentation sheets, Fabaceae, fruit, Ononis, programs, scanning electron microscope, terminal, U.S. National Seed Herbarium.
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(pp. 40-53)
Archeological Botany of the Apple Creek Site, Illinois1
Lawrence Kaplan2 and Shirley L. Maina3
ABSTRACT:
With the advent of flotation and related methods for the recovery of organic remains from archeological sites the identification and interpretation of seeds as culture related soil components has become a most active field. As a result of this activity seed scientists and prehistorians should recognize to a greater extent the importance of the ecology of seeds in the soil. Archeological sites in Illinois and Boston Harbor Islands occupied prior to the introduction of maize agriculture illustrate some of the problems associated with the recovery, analysis, and interpretation of seed remains.

Additional index words: Chenopodium, Iva.
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(pp. 54-71)
Fossil Angiosperm Fruits and Seeds1
Bruce H. Tiffney2
ABSTRACT:
Seed-bearing plants first evolved in the Late Devonian, and subsequently diversified to form many separate and distinct lineages. Of these, the angiosperms are the most recently derived major lineage, and their fruits and seeds are the most common to be found in the fossil record. The fruits and seeds of Cretaceous angiosperms do not appear to be closely related to those of living taxa. However, they show promise of elucidating major lineages within the group, as well as trends in early angiosperm morphology. Modern genera appear in the Early Tertiary and modern species, or their close relatives, in the Mid to Late Tertiary. Through comparison with extant taxa, it is possible to use these fossils to interpret paleoclimates, migrations and the evolution of individual lineages.

Additional index words: Paleobotany, Angiosperm, Fruit, Seed, Cretaceous, Tertiary.
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