64 PROFESSOR O. BUTSCHLIo 



Anteriorly is a flagellum of considerable size, near which are 

 sometimes one or two smaller accessory llagella. Food 

 materials are received into a vacuole formed at the base of 

 the flagellum ; this vacuole in some forms becomes converted 

 into a liplike prominence. A nucleus is present. Repro- 

 duction has as yet only been seen to take place by simple 

 division during the motile stage. According to Cienkowski 

 a cyst is produced in the inner part of the protoplasmic body 

 of the organism, a portion of which is consequently lost by 

 the encystation. 



Spurn ell a termo, J. Clark ('Ann. and Magaz. Nat. 

 Hist.,' 4th ser., vol. i, p. 135, figs. 1 — 4). 



Monas termo, Ehrenberg (?), ('Die Infusionsthiere als 

 vollkommene organismen,' Leipzig, 1838, p. 7, pi. i, fig. 2.) 



These Monads (Plate vi, figs. 1 and 2) were often found 

 by Blitschli as small Flagellata widely diffused in foul water. 

 In spite of a few minor differences they appear to be identical 

 with the form described by Clark, and with the 3Ionas termo 

 of Ehrenberg. Spumella termo is a small organism with a 

 somewhat oval and flattened body ; the greatest thickness is 

 0005 — 0"006 mm. in an average-sized specimen. These 

 small Flagellata are usually more or less fixed by the hinder 

 end of the body, which is not rounded off, although no 

 peculiar shell-like prolongations of this end, produced from 

 the body itself, are visible ; but occasionally, as generally 

 happens in Spumella vulgaris (Cienk.), the posterior end 

 is drawn out into a delicate process. Sometimes the 

 Spumella leaves its resting place and swims about rapidly 

 by means of its flagellum. During the resting stage llie 

 flagellum, which springs from the anterior end of the body, 

 is seen curved in the way figured. 



No accessory flagellum is perceptible in this species. 

 Near the base of the flagellum rises the lip as a corner of the 

 somewhat sharply defined anterior edge of the body. The 

 lip either consists of colourless protoplasm, like the true body 

 of the organism, or it appears more transparent, because it 

 has produced within itself a vacuole filled with fluid 

 (fig. 1 a). This vacuole of the liplike prominence is sub- 

 servient to the reception of food ; thus, the Bacteria and 

 Micrococci, which constitute the chief food of the organism, 

 are driven against the liplike prominence by the lashings 

 of the flagellum ; they either escape or are taken into the 

 vacuole, which is now much swollen (fig. 1 b). The vacuole 

 then passes gradually down, along the side of the body 



