ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 663 



stage the tentacles developed from, as it seemed, tlie middle of the 

 ventral surface ; food was taken in abundantly, but there did not seem 

 to be any parasitic habit. The third stage is that of the free 

 Podophrya, in which the body forms an elongated ellipse, and has the 

 two tufts of tentacles carried to either end of the body, the form of 

 which varies with the amount of food ingested. The fourth phase is 

 that of the fixed or Acineta condition, which is entered upon by the 

 organism surrounding its hinder end with a kind of gelatinous 

 material, which gradually elongates into a more or less tail-like pro- 

 cess. The gelatinous material gradually increases in consistency, 

 and takes on a cup-shaped or infundibular form, 



Pseudo-cyclosis.* — Under this heading Dr. S. Lockwood describes 

 the movement of the food-particles (green unicellular algae) that he 

 witnessed in a specimen of Amoeba diffluens, and which at first sight 

 he mistook for the phenomenon of cyclosis. 



" As the Amoeba advances, the green bodies are left in a cluster at 

 its hinder part. Now the Amoeba's movement stops, and now the little 

 spheroids begin rushing in a well-defined stream towards the advanced 

 portion of the protoplasm. . . . Again the containing body advances, 

 and those contained recede — that is, are left at the hinder part of the 

 protoplasm. We notice also a resting of the host, and the rush forward 

 of the smaller bodies. The Amoeba again advances, this time but a 

 very little. It seems even to recede. Eeally it contracts, then 

 spreads out unsymmetrically on two sides, producing an object not 

 unlike the ankle and foot. Now comes the usual rest succeeded by 

 the movement of the contained bodies, which this time start in two 

 streams, the smaller group towards the heel and the larger to the 

 toes of the so-called foot. This alternating of the two kinds of 

 activities is quite interesting to witness : the streaming inner move- 

 ment always obeying two facts — following a rest of its ^own, and 

 taking the occasion of a rest of the Amoeba." 



In every instance the food-propulsion was a movement in the 

 direction of the outward or forwai'd flow or progression of a part of the 

 Amcuba, and this was always followed by an illusory recession, that is a 

 seeming stream of the little algas backward caused by the advancing 

 protoplasm leaving these objects behind until the new pseudopodium 

 rested, when the trend of the little bodies immediately advanced. 



The object of this movement is to bring the food into actual 

 contact with every molecule of the gelatin body, thus making the 

 entire body take part in the process of digestion, and securing to 

 the whole an equal alimentary distribution. 



New Protozoon.t — Mr. T. Deecke describes an unnamed protozoon 

 which produced perforations in the plates at the bottom of a water- 

 tank made of tinned copper. Furrows radiated irregularly from 

 those perforations as if excavated by a graving tool. The holes and 

 furrows were filled out with an earthy material, consisting mostly of 

 carbonate of copper. When a small piece, still moist, was placed in 



* Amer. Mon. Micr. Joiirn., vi. (1885) pp. H'>-7. 

 t Scientific American, ii. (1881) p. K^*>. 



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