Philodinaea.} TH E INFUSORIA. 403 



transformations, attributable to the influence of parasitic 

 beings. 



" The Rotifer vulgaris travels quite at his ease in these 

 protuberances ; he traverses the partitions, displaces the 

 chromule, and pushes it to the two extremities of the 

 vesicle, so that this appears darker at these parts. One 

 day I opened a protuberance gently ; I waited to see the 

 Rotifer spring out, and enjoy the liberty so dear to all 

 creatures, even to infusorial animals, but no he preferred 

 to bury himself in his prison, descending into the tubes of 

 the plant, and to nestle himself in the middle of a mass of 

 green matter, rather than swim about freely in the neigh- 

 bourhood of his dwelling. 



" Some of these protuberances had greenish threads ap- 

 pended to their free end, and others had none ; I thought 

 at first that these threads were some mucus from within, 

 escaped through some opening which might have served 

 the Rotifer as an entrance, but an attentive and lengthened 

 observation convinced me that in this there was no solution 

 of continuity, and that the arrival of the Rotiferi in the 

 Vaucheriae was not at all to be explained in this way. 

 How are these parasitic animalcules generated within them? 

 This is what further research has some day to show. 

 Meanwhile I have thought that it should be made known 

 that the animalcules found in the Vaucheriae, by linger, 

 was the Rotifer vulgaris of zoologists." 



Found both in fresh and sea water, in infusions, on the 



floccy matters of water plants, &c. Length 1 -50th to l-24th. 



692. ROTIFER (?) citrinus. The citron-coloured Rotifer. 



Body fusiform, lower part gradually attenuated into 



a foot; its horn-like processes elongated, eyes round, 



2p2 



