BIOLOGY OF THE SCOTTISH LOCHS 
315 
submitted to Mr Percy H. Grimshaw are reported upon at the end of 
this paper. 
55. Cliironomus (Blood- worm). — Larvae very common ; found in 
the plankton-nets and also in mud, as deep as 750 feet in 
Loch Ness. 
56. Corethra. — Larvae occasionally abundant in lochs, though 
commoner in ponds. 
57. Oxyetliira^ sp. — Larvae of this Caddis, in beautiful flask-like 
green cases, are often abundant in the margins and 
bottoms of lochs, sometimes going down to considerable 
depths, as in Loch Eilt and Loch Oich ; Inchnacardoch 
Bay, Loch Ness. 
58. Dytiscus marginalis^ L. Loch Earn. 
59. Haliplus fidvus^ L. Harperleas Reservoir. 
60. H. ritficoUis^ De G. Harperleas Reservoir. 
61. Corixa striata^ Fieb. Harperleas Reservoir. 
Larvae of many Diptera, Trichoptera, Perlidae, Ephemerid^e, etc., 
have been collected. 
Crustacea. — Being the most conspicuous animals in the plankton 
of the lochs, the Crustacea have received more attention than the 
more microscopic animals. The Crustacea of the littoral region 
have been studied by Mi* Scourfleld in two systems of lochs, and Mr 
Scourfield has further assisted by naming any species sent to him. 
The list contains 78 species, most of which are common and generally 
distributed. Ilyocryptus acutifrons^ Sars, and Ofliryoxus gracilis^ 
Sars, were not previously known to live in Britain. Fuller informa- 
tion about the distribution of the species, with an account of many 
species not observed by the Lake Survey, will be found in Dr Scott's 
papers on the Inland Waters of Scotland {Scot. Fish. Board Reports, 
1890 to 1899). 
Isopoda. — 62. Asellus acpiaticus, L. 
Amphipoda.— 63. Gcmimarus pidex, F'abr. 
Schizopoda. — 64?. My sis vulgaris Thomps. 
Copepoda. — 65. Diaptomus gracilis, Sars. 
66. D. laciniatus, Lillje. 
67. D. laticeps, Sars. 
68. D. ivierzejshii, Richard. 
69. Cyclops affinis, Sars. 
70. C. alhidus (Jurine). 
71. C. hicuspidatus, (Jlaus. 
72. C.fmhriatus, Fischer. 
73. C.fuscus (Jurine). 
