OF THE TRACHELIN'A. 



619 



which some have supposed to be sto- 

 machs. In stagnant bog-water. 1-72." 

 It has been foimd encysted. (Vide Part I. 

 p. 309). 



T. (?) laticeps. — Flattened, elliptical ; 

 anterior part (head) membranous, vari- 

 able and wide, with a notch from which 

 proceeds a flagelliforni proboscis almost 

 double the length of the body. 1-912". 

 In North Sea. 



T. demlrophihis. — Ovate, subacute at 

 each end ; proboscis verv fine, acute, 

 double the length of the bodv. 1-288'" ; 

 with filament, 1-96'" to 1-72'". Has the 

 habit of a Monad, but the motion of T. 

 trichopliorus, than which it is very much 

 smaller. On ti-ee-mosses. 



T. str ictus (Duj.). — Filiform, extremi- 

 ties rather pointed ; the cilia visible 

 only in front. 1-400". Amongst Lemnse j 

 seen also by Perty in Switzerland. 



T. teres. — Filiform, cylindrical, obtuse 

 anteriorly, pointed and tapering behind ; 

 ciliated only in the anterior margin. 

 1-170". In stagnant sea- water. 



T. Falx. — Long, depressed, lanceolate 



or sigmoid ; variable ; narrower and 

 rather curved anteriorly in a sickle-like 

 form; ciliated generally. 1-420". In 

 pond-water. 



T. noduliferus (Perty). — Very slender, 

 narrowed anteriorly, but terminated 

 abruptly by a rounded end; colom-less, 

 but with diffused chlorophyll-vesicles at 

 times, and granules. Cilia scarcely vi- 

 sible, except near the head, where they 

 are rather larger. Movements slow. The 

 elongated neck-like portion devoid of 

 molecules. 1-570" to 1-120" (Bern). 



T. apicidatus. — Slender, tapering an- 

 teriorly, its end being obtuse. Colom*- 

 less, with diffused vesicles and molecules. 

 Cilia very delicate. Movements rapid, 

 like those of Trachelocerca. 1-144". 



T. pusiUus. — Considerably elongated ; 

 rather flattened; colomiess; with a round 

 opening at its naiTower anterior ex- 

 tremity. Movements tolerably quick, 

 with slow revolutions on its axis. 



Perty intimates it to be the same 

 species as Trachelius trichophorus (Ehr.) 

 and the Peranema protractum (Duj.). 



Genus LOXODES (XXIV. 291-293).— Body ciHated throughout, mouth 

 simple, devoid of teeth ; upper lip continuous and broad, hatchet-shaped ; 

 locomotive cilia longer near the mouth. The contractile vesicle is round ; 

 the nucleus oval or ovoid. In L. Bursaria an oval nucleus and two contrac- 

 tile globular vesicles have been seen. Self- division transverse. 



Dujardin's characters of Loxodes are — " Body flat, membranous, or with an 

 apparently membranous lorica, flexible but not contractile, expanded at the 

 centre of its superior or dorsal siu-face, often concave on the under siuface ; 

 contour irregularly oval, sinuous and obliquely prolonged anteriorly ; fiimished 

 with very fijie cilia, confined to its anterior margin. In general characters," 

 he adds, " Loxodes approaches nearest to Trachelius (family Trichodina) ; but 

 the signs of an integument are so clear as to sever it from that genus and 

 family." The Loxodes described by the French author are almost all of them 

 distributed by Ehrenberg among other genera and families ; and hence there 

 is unfortimately none but the slightest relation between the similarly-named 

 genus of the two writers. Thus the Loxodes JRostrum of Ehrenberg is the 

 representative of a genus Pelecida, of the family Trichodina, in the system of 

 Dujardin, and bears the name of Pelecida Rostrum. In this position it is 

 brought into close relation with the genera Triclioda and Tixichelius (Ehr.), 

 and with two others, named by Dujardin Aciduria and Dileptus. 



The last-mentioned genus comprises Infusoria placed by Ehrenberg with 

 Ampliilep)tus, in describing which we shall take the opportunity to give the 

 characters of Dileptus, whilst Acineria and Pelecida will be included among 

 the appended genera at the end of the present family, Trachelina. 



Loxodes Rostrum {Kolpoda Rostnmi, 

 M., Pelecida Rostrum, D.) (xxiv. 291- 

 293). — Body compressed, white, lanceo- 

 late, slightly curv^ed in the form of an S, 

 in consequence of the lip being a little 

 uncinated. Ehrenberg states that he has 



very often seen large Navicidce and Syn- 

 edrcB within this creature, although it 

 would not feed on colom'ed food. The 

 cilia are very delicate, (xxiv. 291, an 

 animalcule which has fed upon Bacil- 

 laria ; xxiv. 292, another, creeping along 



