Now showing items 1-10 of 84
Choosing category size in a stage projection matrix
(Springer-Verlag, 1978-01)
A basic problem associated with choosing category size in a stage projection matrix is described. “Errors of estimation” are large if the category size is chosen too small and “errors of distribution” are large if the ...
The presence of protease activity in the rectal fluid of primitive attine ants
(Elsevier, 1971-10)
The excretion of proteolytic enzymes by representative species of the attine genera Atta, Acromyrmex, Sericomyrmex, Trachymyrmex, Myrmicocrypta, Apterostigma, and Cyphomyrmex has been established. The significance of ...
Faecal proteinases of the fungus-growing ant, Atta texana: Properties, significance and possible origin
(Elsevier, 1975-10)
The proteolytic activity previously reported in the faecal fluid of fungus-growing ants is due to the presence of three enzymes. These enzymes have been partially purified and characterized. One is a serine proteinase; the ...
Cell elongation in the grass pulvinus in response to geotropic stimulation and auxin application
(Springer-Verlag, 1976-01)
Horizontally-placed segments of Avena sativa L. shoots show a negative geotropic response after a period of 30 min. This response is based on cell elongation on the lower side of the leaf-sheath base (pulvinus). Triticum ...
Non-visual functions of crustacean eyestalk ganglia
(Springer-Verlag, 1971-03)
Ablation experiments demonstrated that in several crustacean groups, the proximal eyestalk ganglia are important in a variety of behavior patterns: 1. Chemical elicitation of feeding via the antennules is altered in lobsters, ...
Current status of the Progymnospermopsida
(Elsevier, 1976-01)
The three progymnosperm orders, Aneurophytales, Protopityales, and Archaeopteridales, are characterized and analyzed. The possibility that some of the apparent taxonomic diversity of the Aneurophytales and Archaeopteridales ...
An idealized concept of the true cladistic character
(Elsevier, 1975-04)
Estimating evolutionary relationships is basic to the objectives of systematics. Comparative data, structured as taxonomic characters, are usually the essential considerations on which such estimates are founded. Some ...