528 ORDER HOLOTRICHA. 



frequently complex through the addition of lateral diverticula ; tricho- 

 cysts usually present. 



The animalcules of this genus most nearly resemble those of AtnphUcptus, but 

 are much more flattened in shape, while the anterior extremity, though usually more 

 flexible and attenuate, is not developed so as to form a separate trunk or proboscis. 

 As instituted by Dujardin * the genus Loxopliylluiii included only the Amphikptus 

 mdeagris of Ehrenberg, his diagnosis as constructed thereon including such fonns 

 only in which the margins of the leaf like body are sinuous or undulate, and the 

 cuticular cilia distributed in widely separated parallel rows. As shown, however, by 

 Claparede and Lachmann, these last-named characters have merely a specific value. 

 In common with the other representatives of the Tracheliidx the members of the genus 

 Loxophyllum are apt to become distended and inflated, through the inception of 

 food-particles, though at the same time not to such an extent as to completely dis- 

 guise their normal lamellate contour, a thin flattened marginal border at all times 

 remaining conspicuous. The Loxophyllum fasciola of Claparede and Lachmann, 

 identical with the Amphikptus fasciola of Ehrenberg and the Dihptus folium of 

 Dujardin, has been removed, in accordance with the recent discoveries of 

 Wr/,esniowski, to the Hj^potrichous genus Litonotus. 



Loxophyllum meleagris, Ehr. sp. Pl. XXVII. Fig. 52. 



Body leaf-like, obliquely lanceolate, highly elastic, about three times as 

 long as broad, the anterior extremity pointed and curved towards the 

 dorsal aspect ; the dorsal border crenulate ; oral aperture situated on the 

 ventral side close to the anterior extremity ; contractile vesicle spherical, 

 postero-terminal, communicating with a canal-like prolongation, that extends 

 along the dorsal margin nearly to the anterior extremity of the body; 

 cuticular cilia disposed in distinct longitudinal parallel rows ; endoplast 

 single, ribbon-like, or forming a moniliform chain of bead-like nodules ; 

 trichocysts abundantly developed, usually forming a continuous series along 

 the ventral border. Length 1-75". Hab. — Pond water. 



This species, which is identical with the Amphikptus meleagris of Ehrenberg, is 

 the type upon which Dujardin instituted the present genus. The Trachelius 

 mcka'gris of the first authority is, as already mentioned, referable to the genus 

 Amphikptus. According to the recent researches of \Vrzesniowski,t considerable 

 differences exist between animalcules referable to this type obtained from separate 

 localities. Thus, while at Warsaw the examples gathered conformed entirely with 

 the diagnosis above given, those at Grogec were of extremely attenuate proportions, 

 no less than seven or eight times as long as broad, and exhibited a further important 

 difference in the number and arrangement of the trichocysts. The latter structures 

 formed not only a continuous row throughout the ventral border but were also present 

 in bundles on the dorsal one ; these bundles, again, were not distributed in regular 

 order, but one occupied a position corresponding with the projecting portion of each 

 marginal undulation. This so-called variety, seeming to merit separate specific dis- 

 tinction, the present author is disposed, in honour of its discoverer, to provisionally 

 confer upon it the title of Loxophyllum Wrzesniowskii. The character of the con- 

 tractile vesicle of L. meleagris, with its diverging canals, and also that of the endoplast, 

 is well illustrated in Wrzesniowski's excellent figures of this species. The breaking 

 up of the primary band-like contour of this latter structure results in the production 

 of a number of fragments of variable size which, while apparently scattered at random 



* ' Histoire des Zoophytes Infusoires,' Paris, 1854. 



t ' .\rchiv fur Mikruskopische Anatoniie,' Bd. v., 1869. 



