Land and Fresh-Water Crustacea around Edinburgh. 373 
Suborder Gymnomera. 
Family POLYPHEMIDAZ. 
Genus Polyphemus, O. F. Miiller. 
Polyphemus pediculus (Linné). 
1746. Monoculus pediculus, Linné, Faun. Suec., No. 2048. 
1776. Polyphemus pediculus, O. F. Miiller, Zool. Dan. Prod., No. 
2417, 
1850. Polyphemus pediculus, Baird, Brit. Entom., p. 111, pl. xvii, 
fig. 1. 
Polyphemus was obtained in Raith Lake and in Loch 
Leven. This species seems to have a preference for moder- 
ately large sheets of water. It was frequent in Loch Ness, 
Loch Oich, and Loch Lochy in 1890; abundant in Loch 
Morar in 1892; frequent in Loch Tay in 1893; and in 
Middle Loch, ehiia of Mull. 
Genus Bythotrephes, Leydig. 
Bythotrephes longimanus, Leydig. 
Bythotrephis longimanus possesses an enormously long 
post-abdominal spine; it has otherwise somewhat the aspect 
of a Polyphemus. The only locality within the area where 
it has been obtained is Loch Leven, Kinross-shire. I found 
it common in Loch Ness and Loch Oich; frequent in Loch 
Morar; and rather scarce in Loch Tay. I have also notes 
of its occurrence in Loch Scuban and Middle Loch, island 
of Mull. 
Family LEPTODORIDA. 
Genus Leptodora, Lilljeborg. 
Leptodora hyalina, Lilljeborg. 
This beautiful species was obtained in Loch Leven, but 
nowhere else within the district. It was moderately common 
in some of the tow-net gatherings from that loch. I also 
found it frequent in Loch Morar tow-net gatherings, and 
