1885.] 



MICEOSCOPICAL JOURNAL. 



47 



these little bodies, nearly thirty in 

 number, are amoeba's dinner. It is 

 gorged, and the work in hand is to 

 digest the rich repast. As amceba 

 advances the green bodies are left in 

 a cluster at its hinder part. Now the 

 amceba's movement stops, and now 

 the little sphei'oids begin rushing in a 

 well-defined stream towards the ad- 

 vanced portion of the protoplasm. 

 They seem tiny greenings bowling 

 along a grassy way. Again the con- 

 taining 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. Really 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 in- 

 teresting to witness : the streaming 

 inner movement always obeying two 

 facts — following a rest of its own, 

 and taking the occasion of a rest of 

 the amoeba. 



As to this rest of the amoeba, is it 

 actual or only apparent ? As to pro- 

 gression, it is an actual rest, but I 

 cannot imagine this throbbing and 

 rapid streaming to be due to any 

 osmotic force. Its regularity really 

 suggested a systole and diastole con- 

 tractility of the pulsating vesicle. 

 Says Gegenbaur : ' Any place in the 

 protoplasm can act as a digestive 

 cavity by enveloping and absorbing 

 nutritive matter, and at any neigh- 

 boring part of the surface the undi- 

 gested substances can be expelled.' 

 Hence the object of this streaming of 

 the little bodies into every projected 

 lobe or new pseudopodium, thus 

 bringing the food into actual contact 

 with every molecule of the gelatin 



body, making the entire body to take 

 part in the digesting, and securing to 

 the whole an equal alimentary distri- 

 bution. 



This microscopic speck of lifc-stuB', 

 or, as Clarke calls it, ' transparent 

 sarcode — structureless animal tissue,' 

 has no composition of parts. The 

 exterior is likely a little denser than 

 the interior, in which is that little 

 cavity which may come and go, that 

 is, be and not be, which is called a 

 v'acuole. Hence such terms as endo- 

 sare, ectosare, endoplast, and others, 

 are rather too subtle and refined. Yet 

 Clarke describes and figures his struc- 

 tureless being as revolving its food in 

 true cycloidal movement. The scene 

 I have described was witnessed for 

 one entire hour. In every instance 

 the food propulsion was a movement 

 in the direction of the outward or 

 forward flow or progression of a part of 

 the amoeba, and this was always fol- 

 lowed by an illusory recession, that 

 is a seeming stream of the little algie 

 backward, caused by the advancing 

 protoplasm leaving these objects be- 

 hind until the new pseudopodivmi 

 rested, when the trend of the little 

 bodies immediately advanced. For 

 this phenomenon I have used the 

 word pseudo-cyclosis. My desire 

 was to watch until digestion had be- 

 come complete, but this privilege 

 was denied. 



o , 



Method of Analysis of Fibres, 

 Tissues, Etc.* 



By testing all the fibres we have 

 enumerated, and using the indications 

 we have given, one is able to identify 

 them with certainty and without dif- 

 ficulty, whether they are alone or min- 

 gled with others, in the form of a tis- 

 sue, or any product of agriculture or 

 industi'y. But inquiries of this kind 

 are often simplified and much facili- 

 tated by working methodically. We 

 think, then, we are i^endering a service 

 by furnishing a table in which we have 

 arranged in a certain order the more 



* From ' ttudes Bur les Fibres,' by M. Vetillart. 

 Translated for this Journal by Rufus W. Deering. 



