306 ORDER FLA GELLA TA-PANTOSTOMA TA. 



centre of the lateral periphery ; endoplast situated in the median line, 

 towards the anterior extremity. Diameter of spheroidal zooids 1-2500". 

 HAS. Pond water. 



Stein * proposes to identify this type with both the Monas guttula of Ehrenberg 

 and the more recently introduced Spumella vulgaris of Cienkowski. It would seem 

 just possible that the first-named identification is correct, but no mention is made 

 by Ehrenberg of its most characteristic fixed existence and attachment by a special 

 caudal filament, and which would undoubtedly, if recognized, have influenced that 

 authority to relegate the animalcule to his caudate genus Bodo. Stein agrees with 

 Cienkowski in allotting to this form the presence of two minute supplementary 

 flagella at the base of the more conspicuous axial one ; he further figures what he 

 interprets to be the genetic union between a normal sedentary, and a minute motile 

 zooid, the latter attaching itself to one side of the larger one, and becoming absorbed 

 into its substance, the phenomena corresponding with those exhibited during the 

 genetic union of the larger sedentary and minute migrant zooids of Vorticdla, 

 first discovered by this same authority and described later on. In specimens of 

 this type, recently examined by the author, obtained in pond water containing 

 Acineta mystacina and Salpingceca gracilis, the presence of the one long and two 

 rudimentary flagella was fully certified, as also the existence of the linear furrow-like 

 mark near the anterior border, interpreted by Stein and Cienkowski as representing 

 a distinct oral aperture. That no such ingestive function can be assigned to it was 

 however conclusively demonstrated through the witnessing on numerous occasions 

 'of the inception of solid food-particles at the most diverse regions of the periphery. 

 As in the case of Oikomonas, Amphimonas, Anthophysa, and numerous other Panto- 

 stomatous Flagellata already described, such food-inception was manifested by the 

 temporary rupture of the peripheral wall of the animalcule's body at whatever 

 point against which the food-particle was thrown by the flagellum, accompanied by 

 the simultaneous outflow of the softer inner sarcode which enveloped and secured 

 the welcome morsel. Under such circumstances there can be but little doubt that 

 this so-called oral furrow is, as in the case of Goniomonas truncata, as interpreted 

 by Biitschli, a mere linear granular deposition corresponding morphologically with 

 the red or other coloured pigment-spots common to Euglena and various ordinary 

 Flagellata. Such a granular pigmentary interpretation entirely accords with the 

 decision arrived at by the author in connection with the present species, after care- 

 fully submitting it to the highest available magnifying power. It would seem to 

 be by no means improbable that Stein's representation of the presumed coalescence 

 of a minute free-swimming zooid with a larger sedentary one, as here reproduced, 

 Plate XIV. Fig. 49, might be more accurately interpreted as an example of the 

 ingestion of a foreign food-particle at the lateral periphery. 



Spumella vivipara, Ehr. sp. PL. XIV. FIGS. 34-36. 



Body when attached usually obovate, widest and rounded anteriorly, 

 tapering to a point at its posterior extremity; exceedingly plastic and 

 changeable in shape, ovate, spheroidal, or elongate in its free-swimming 

 state ; one long axial and two short lateral flagella ; endoplasm transparent, 

 enclosing innumerable constantly vibrating refringent corpuscles ; a short 

 linear pigment-band or furrow-like mark situated close to the anterior 

 border ; pedicle short, scarcely equalling the body in length ; contractile 

 vesicle single, located near the centre of the lateral border; endoplast 

 median, anteriorly situated. Length i-iooo" to 1-620". 



HAB. Fresh water and infusions. 



* ' Infusionsthiere,' Abth. iii., 1878. 



