﻿Fresident's Address. 



19 



fresh-water Triclads I have myself recently been giving some 

 attention, and have a short paper on them nearly ready for 

 publication. Rhynchodemus terrestris (Miill.) — probably our 

 only indigenous terricolous Triclad — is not uncommon,^ and 

 the exotic Flacocephalus {Bipcdmm) kewensis (Moseley) seems 

 to be established in a few greenhouses.- The following 

 fresh-water species, Planaria ladea^ Miill., P. alpina, Dana 

 (P. arethusa, Dalyell), and Polycelis nigra, Ehr., are all 

 common : P. cornuta, Schm. {felina, DIL) I have also found, 

 and the marine Gunda ulvce, Orst. (once at Dunbar). 

 Of the minute Ehabdocoelida there must be many both 

 marine and fresh- water. Dalyell knew a number from 

 the east of Scotland, mainly no doubt from " Forth," but 

 as often as not he omits to state the locality, so that, apart 

 from the difficulty of identifying his species, his works 

 furnish comparatively few records.^ 



"When the Turbellaria of " Forth " have been properly 

 investigated, I anticipate a list of from 40 to 50 : at present 

 we know of little more than a dozen. From St Andrews 

 Bay, close to the mouth of the Forth, Professor M'Intosh has 

 recorded a number of marine species."^ 



Trematoda. — The Trematodes, like other parasitic worms, 

 have not yet received the attention they deserve. The best 

 known is the liver-fluke, Distomum hepatimm, with whose 

 intricate life-history every student of zoology is familiar. Of 



^ W. Evans, Aivn. Scot. Nat. Hist., 1905, p. 57. 



^ A specimen (from a greenhouse at Corstorphine) was exhibited by Pro- 

 fessor J. Arthur Thomson at a meeting of this Society, 20th January 1897 

 {Proceedings, xiii. p. 396); and it has been known for a number of years in 

 hot-houses at the Royal Botanic Garden (Dr Stewart MacDougall, Trans. 

 High, and Agric. Soc, 1905, p. 280). Dr Caiman states {Ann. S. N. H., 

 1902, p. 233) that a large planarian which he has examined from the Botanic 

 Garden approaches most closely to Rh. hallezi, v. Graff. 



^ Taking von Graff {op.cit.) as a guide, we may admit the following as 

 "Forth" records of Rhabdoccelids : — Microstoma linea.re, Orst. {P. falcata, 

 DIL), Lochend ; Mesostoma rostratum, Ehr. (P. velox, Dll.), near Linlithgow ?, 

 (Loch Leven, July 1906, W. Evans) ; Vortex viridis,'M. Sch. {P. graminea, DIL), 

 near Linlithgow, without doubt ; Derostoma unipunctatum, 0. (P. fodince, 

 Dll. ), old quarry at Fenton Tower, Haddingtonshire. A few others are less 

 certain. Gamble {I.e.) gives "Firth of Forth" as the locality for several of 

 Dalyell's unlocalised marine Planarians. Convoluta 'paradodxt, O. (P. Tiau- 

 strum, Dll.), was from Eyemouth, which is scarcely in the Firth of Forth: 

 I have, however, found it abundantly at Dunbar, and also at North Berwick. 



^ ' Marine Invertebrates and Fishes of St Andrews,' 1875. 



