GENUS CODONCECA. 261 



Doubtful Species. 



The Cercomonas detracta, C. viridis, C. lacryma, C. acuminata, C. truncata, and 

 C. lobata of Dujardin would appear in a similar manner to represent transitional or 

 amoeboid phases of other monadiform types. The Cercomonades intestinalis, curvata, 

 vorticellaris, ranarum and facula of Perty are apparently for the most part referable 

 to the genus Bodo of Ehrenberg, and in no instance conform with the amended 

 diagnosis of the genus here adopted. Stein's recently figured Cercomonas termo 

 (Oikomonas Steinii), C. musca-domestica, C. ramulosa and C. obesa exhibit, in no 

 instance, that essential characteristic of a true representative of the genus Cercomonas, 

 as manifested by the possession of a persistent caudal filament ; these three types 

 are here distributed among the two genera Herpetomonas and Monas proper. 



Fam. IV. CODONOECID^J, S. K. 



Animalcules inhabiting a horny sheath or lorica ; flagellum single, 

 terminal ; no distinct oral aperture. 



GENUS I. CODONOECA, James-Clark. 



Animalcules solitary, uniflagellate, inhabiting an erect pedicellate lorica, 

 to the bottom of which they are fixed in a sessile manner, and not attached 

 to the same by a secondary flexible pedicle. HAB. Salt and fresh water. 



This genus was established by Professor H. James-Clark for the reception of a 

 single species, differing most essentially from JBicosceca in the absence of the 

 flexible pedicle, which in the latter genus unites the animalcule with the base or 

 fundus of the lorica, and by its possession of a single flagellum only. To the single 

 marine species first discovered by Professor Clark, a second, fresh-water type is 

 here added. 



Codonceca costata, Jas.-Clk. PL. XIV. FIG. 53. 



Lorica campanulate, divided by a constriction into two regions ; the 

 basal third obconical, tapering gradually towards its junction with the 

 pedicle, the anterior two-thirds bulging out abruptly but narrowing again 

 slightly towards the terminal aperture ; the inflated portion sulcated 

 longitudinally by about twenty or thirty equal furrows, which impart a 

 scalloped aspect to the anterior margin ; pedicle equal in length to the 

 lorica, somewhat uneven. Contained animalcule elongate - ovate, the 

 posterior end rounded, half filling the narrower proximal third of the lorica, 

 the anterior end somewhat pointed ; flagellum vibratile, projecting con- 

 siderably beyond the orifice of the lorica ; colour dingy yellow. Length of 

 lorica 1-1500". HAB. Saltwater. 



The singular form and elegant sculpturing of the lorica of this species in some 

 respects agrees with that of the collared monad Salpingoeca ampulla, hereafter 

 described. But a single example of this type has been so far met with by the 

 author, and in that instance an empty lorica only, attached to sea-weed obtained 

 from the Crystal Palace aquarium. 



Codonceca inclinata, S. K. PL. XIV. FIG. 54. 



Lorica simply ovate, not sulcate longitudinally, attached obliquely to a 

 pedicle of twice its length. Contained animalcule ovate, occupying the 



