Reports comparison of three models of apparatus designed to collect gas evolved by a photosynthesizing water plant. Problems of design and operation are reported for each model. (AL)

Procedures for constructing an inexpensive, illuminated, monocular, low-powered microscope are presented. Materials include a commercial lens and a specially designed plastic moulded stand which incorporates a bulb holder and opaque plastic stage. (Author/DC)

A polarizing microscope can considerably enhance the teaching of plant anatomy. Instructions for adapting a normal teaching microscope for use as a polarizing microscope are provided. (JN)

Suggested specifications for microscopes for various applications are given. A discussion of the ways of meeting these specifications in practice is illustrated by current models from British and foreign manufacturers. (BB)

The use of green, red, and far-red light-emitting diodes (LEDs) as light sources for plant physiological studies is outlined and evaluated. Indicates that LED lamps have the advantage over conventional light sources in that they are lightweight, low-cost, portable, easily constructed, and do not require color filters. (Author/DH)

Described is a simple experimental system, which uses radioactive carbon dioxide to study whole leaf photosynthesis under a variety of conditions. Other experiments and simple apparatus for the experiments are also described. (Author/RH)

Describes a modification in the use of artificial substrates to study attached micro-algae. Apparatus is based on glass microscope slides immersed in natural water environments; biomass and primary productivity are assessed by measurement of alpha-chlorophyll. Describes use in studies of colonization, succession, and populational fluctuation. (CS)

Provides illustrated directions for the construction and use of a low-cost thermistor device. Attached to a servo-type millivolt chart recorder, the device will record minute temperature changes and will simulate data obtained from an oxygen polarograph. Includes results of experiments with baker's yeast. (Author/CS)

Describes construction and use of a simple auxanometer which students can use to accurately measure root growth rates of intact seedlings. Typical time course data are presented for the effect of ethylene and indole acetic acid on pea root growth. (Author/BR)

Simple jigs (positioning devices) to make contour mapping tasks easier and more accurate are easily constructed from 5mm-thick acetate sheets. These plastic holders are used with meter sticks to provide scanning guides to measure pools and ponds. Instructions for making the jigs and sample results are included. (DH)

Describes the construction, design, and operation of an inexpensive, precision, multiple seed planter. (JN)

Describes a simple, inexpensive continuous culture apparatus (chemostat) and its applications in teaching biological concepts (growth-limiting factors and competition). Other suggested uses include experiments in enzyme induction, biosynthesis, and strain selection, and for student research projects. (JN)

Describes layouts for converting a high-top van into a multipurpose laboratory and transport for a college biological sciences department. (CS)