1894.J MICROSCOPICAL JOURNAL. 199 



ies commonly referred to as " oil globules," have an in- 

 dependent motile power of their own, and when they are 

 relatively few and scattered, and when not densely 

 packed, the amplitude of oscillation of a group of three 

 or four of the globules is readily followed, and in a group 

 of three of these globules of the same or of various sizes, 

 one of them may glide between the two others, making a 

 cross over, thus reversing its position with reference to 

 the two others which makes the phenomenon of motion 

 very evident and noticeable. In reference to this, it may 

 be noted that Prof. Smith, in referring to these so called 

 "oil globules" always put an interrogation mark after 

 "oil," thus " oil ? globules," thus indicating some degree 

 of doubt or uncertainty as to their real nature or function 

 but as the reagent ether dissolves them, the reaction sug- 

 gests that they are of an oleaginous principle. These so 

 called " oil globules " were the only possible morpholog- 

 ical condition that could have induced or lead Ehrenberg 

 to regard them as stomachs, as there is nothing else evi- 

 dent that has a structural shape that can be specifically 

 made out excepting the nucleus, an organ which I have, 

 so far, not been able to discriminate, identify or detect, 

 the zone-like bands or layers of endochrome being ap- 

 parently homogeneous or structureless and blending into 

 varying shades of green or brown and gradually vanish- 

 ing in the body of the transparent endoplasm which is 

 usually colorless towards the middle of the frustule on 

 either side, away from the nodular depressions. 



Ordinarily at the median nodules, an indistinctly gran- 

 ular appearance is noted in the endochrome and it is 

 within this area, the nucleus is to be looked for when the 

 conditions favor glimpsing it. This area intervening be- 

 tween the nodules, seems to act as a partition, dividing 

 the endoplasm into halves and within each half may be 

 seen irregularly scattered, the globular bodies of vari- 

 ous si^es and irregularly distributed within the more 



