LECyTHIUM. GRANULATUM. Ill 



Pamphagus granulatiis 



Pbnaed Faune Rhiz. Lernan (1902), pp. 435-437, 9 figs. ; Sarcodines 



grands Lacs (1905), pp. 108, 117; Sarcodines in Cat. Invert. Suisse 



(1905), p. 87 ; in Rev. Suisse Zool XX (1912), pp. 18-22. pi. ii, 



ff. 16, 17. 

 AvBKiNTZBFF in Trudui S.-Peterb. Obslicli. XXXVI, ii (1906), pp. 



267-268. 

 ScHOTJTBDBN in Ann. Biol, lacustre, I (1906), pp. 361, 362. 

 HooGBNEAAD in Tijds. Neederl. Dierk. ^er. (2) X (1908), pp. 415- 



416, 424 ; in Ann. Biol, lacustre, III (1908), p. 255. 

 Brown in Ann. Scott. Nat. Hist. 1911, p. 229 ; in Naturalist, 1912, 



p. 181. 

 Wailbs & Pbnaed in Proc. R. Irish Acad. XXXI, Lxv (1911), p. 18. 

 "Wailbs in Scott. Natur. 1912, p. 60. 



Envelope spheroidal or pyriform, membranous, 

 hyaline, supple ; often distorted by the ingestion of 

 large diatoms ; aperture terminal, normally circular 

 but capable of taking various forms ; plasma colourless, 

 completely filling the test, containing large refringent 

 globules and smaller granules ; nucleus large, granular, 

 placed posteriorly ; one large contractile vesicle and 

 several vacuoles usually present; pseudopodia long, 

 radiating, simple or branched. 



Length 40-140 ju, or more ; breadth about half the 

 length. 



Habitat. — Aquatic vegetation. 



England. — Derbyshire {Brovm) ; Devonshire. 



Wales. — Snowdon, Carnarvonshire, 3000 feet (West). 



Scotland. — Outer Hebrides ; Glen Shee, Perthshire 

 (Broicn). 



Ireland. — Clare Island, Mayo; ? Wicklow (Archer). 



The normal form of the test in this species appears 

 to be ovoid or spheroidal, but its habit of distending 

 itself with a large number of diatoms or filamentous 

 and other Algse (Spirogyra, Desmidium, etc.) distorts 

 the membranous test into various shapes, usually 

 elongated and more or less pointed at the posterior 

 end. Small and compact aggregations of diatoms have 

 been noted by many observers and were generally 

 regarded as " cysts " and as having some connection 

 with their life-history. Penard * has no doubt that 



* 'Revue Suisse de Zool.,' loc. cit. supra. 



