They are members of the Phylum Crustacea and the order Amphipoda. They can reach 20 mm in length and their habits can easily be observed by eye or 10X hand lens in a shallow dish. They are laterally compressed and swim on their side and typically eat organic debris. Their body and leg structure is worth studying, which are shown in the images heading this and the previous section. Go back to this Walk's Contents Algae Algae are single-celled plants and include microscopic forms less than 1 micron long to the giant seaweed called kelp which can reach lengths of 60m.
Many algae are very attractive particularly if dark ground illumination is used.
Most ponds contain various filamentous algae and the green 'slime' often found in ponds is composed of algae. The cellular structure of the algae can be examined with modest powers of 100-200X using the traditional 'high power' microscope rather than the low power stereo. One of the general guides on algae may allow identification to genus. In the sample taken by the author, some of the algal filaments were undergoing conjugation, and is shown on the image on the right above. This is sexual reproduction and involves two filaments lying side by side joining by the formation of outgrowths.