BIOLOGY OF THE SCOTTISH LOCHS 
319 
166. Mesostomum viridiatum. Loch Tay (C. H. 
Martin). 
167. M. prorhynchus^ Loch Tay (C. H. Martin). 
168. Vortex truncatm, Ehr. Loch Tay (C. H. 
Martin). 
169. Polycystis goettei^ Bresslau. 
170. Aiitomolos morgicnsis (Du Plessis). Lochs 
Ness, Tay, Earn. 
171. Gyrator noto ps. 
Notes on the Species 
Hiruclo 7nedicmaUs, L. — Found in Loch Earn, the medicinal leech 
may readily be supposed to have been introduced. Dalzell, however, 
records it from a smaller and remote loch in the same district. 
Eid)0st7^ichus ? sp. — Certes ^ wrongly included in the genus 
Eubost^ichus, Greeff', a curious worm, the position of which is not yet 
definitely settled. In the head is a long trumpet-shaped body which 
is said by Certes to be a dart, which can be protracted. The body 
is annulate, and each ring bears six spines, which form six longi- 
tudinal rows on the body. The form found in Loch Lomond is 
undoubtedly related to that provisionally named Eiihostriclms guernei 
by Certes, but differs in having numerous spines on each ring, which 
do not form distinct longitudinal rows. 
Microstoma lineare^ Oerst. — Mr Martin found this species in Loch 
Tay feeding on Hydra^ and carried out a very interesting investigation 
into the subsequent history of the nematocysts of the Hydra. 
Automolos morgiensis (Du Plessis). — At depths of 20 feet to 500 
feet in Loch Tay, over 700 feet in Loch Ness. Mr Martin states 
that those dredged from 500 feet in Loch Tay had no eyes. 
Stylodrilus Gabreteas, Vejd. — Like Automolos morgiensis^ this is an 
abyssal species. It is general at depths of over 100 feet, but is 
sporadic in shallower waters. 
Rotifera. — A larger number of Rotifers is recorded for the 
Scottish lochs than of any other class of animals or plants. This 
may be partly due to the fact that they are very numerous, — by closer 
work the list might easily be extended to 300, perhaps 400 species, — 
but may be partly accounted for by the attention paid to them, and 
the facility with which they can be transmitted alive to specialists. 
Some other classes which are poorly represented in these lists — 
Infusoria, for example — may be really more numerous. The single 
family of Desmids contains more species than any one familv of 
Rotifers, and the Diatoms are probably equallv numerous. Eleven 
^ Mission Scientifique du Cav Hor)i, Paris, 1889, p. 48. 
