of the Fishery Board for Scotland. 
273 
Candma Candida (Miiller). Generally distributed, frequent. 
ladea, Baird. Generally distributed, frequent. 
kuupleii, Brady and Robertson. North shore, not common. 
pidicsccns (Koch). Frequent and generally distributed. 
Ilyocypris gibha (Miiller). North side frecjuent ; south side rare. 
Cytheridca lacustris (G. 0. Sars). Frequent all over the bottom of the loch. 
Limnicythax sancti-patHci, Brady and Robertson. Generally distributed, 
common. 
iriopinata, Baird. Generally distributed, not common. 
Cladocera. 
Daphnella hrachyura (Lievin). Generally distributed, not common. 
Daphnia pulcx (JsixiWev). Generally distributed, frequent. * 
,, longispina, Miiller. Generally distributed, abundant. 
Bosmina longirostris, Miiller. In surface tow-nettings, rare. 
Ilyocryptus sordidus (Lievin). South shore, frequent. 
Euryccrcus lamellatus (Miiller). Generally distributed, not common. 
Acroperus harpa, Baird. North and south shores, frequent. 
Alooiopsis ehngata, G. 0. Sars. South shore, not common. 
Alona qiLadmngularis, Miiller. Common, north and south shores. 
Alonella exigua, Lilljeborg. Frequent, north and south shores. 
nana, Baird. South shore, scarce. 
Pleuroxus trigonellus, Miiller. Connnon in the loch. 
uncinatus, Baird. In the middle of the loch, scarce. 
Chydorus sphcericics, Miiller. Generally distributed, common. 
Monospilus tenuirodris, Fischer. South shore, scarce. 
Folyphemiis pedicuhis (Linne). Middle of the loch, scarce. 
Bythotrcphcs longimanus, Leydig. In the middle of the loch, frequent. 
Lcptodora hyalina, Lilljeborg. In the middle of the loch, frequent. 
INSECTA. 
The larvae of insectvS were abundant in the loch, especially the larvae of 
the Iphemeridse. The Libellulidse and Phryganidas were also represented 
in the larval stage more or less frequently. Some idea may be formed of 
the myriads of these organisms present in the loch when it is stated that a 
conspicuous ridge composed of cast-off skins of insect larvse which had 
been washed ashore during the preceding stormy weather extended along 
the margin of the loch for a considerable distance. The curious so-called 
* water-bears ' (Tardigrada), now included in the class Arachnida, were 
common among the decaying vegetable matter at the bottom. Species of 
Notonectidse or ' water-bugs,' and of aquatic Coleoptera were also more 
or less common, though their distribution seemed to be more localised. 
VERMES. 
This division of invertebrates was represented by several species — para- 
sitic and non-parasitic. Among the former were Scliistocephalus solidus, 
Crepl., obtained by my son from the body-cavity of a Stickleback {Gas- 
terosteus aculeatus), and a species of tape-worm (Bothriocephalus latus ?) 
several of which were found in the alimentary canal of the trout, six speci- 
mens being taken from one fish. The heads of the parasites were fixed at 
the extreme end of the cceca or blind tubes of the stomach, and their bodies 
were so elongated as to extend well down into the intestine. Usually 
one parasite occupied a caecum. Tuhifex rivulorum was very common in 
the loch. The following species of Annelida? were also obtained : — 
Clepsine 6 — oculata. 
Clepsine sp., a very small form. 
Nephelis octoculata (JN. reticulata, Malm. ). 
S 
