The Microscope 356 



mm. long and narrower, being imperfect hexagons. The outer 

 walls of these cells are thin, transparent membranes, and are 

 well marked with lines, thickenings, wrinkles or folds, appearing 

 much like the strife figured by geologists for glacially scratched 

 rocks ; the partitions are thicker, averaging about b/j- thick, 

 being more or less variable. 



We observe that our little boxes — cells — are lined with a 

 gelatinous substance, more dense than the clear cell sap within, 

 therefore, visible as a distinct substance, although also trans- 

 parent ; this is the protoplasm ; while this lines the walls of the 

 cells the central portions are filled with the clear, limpid fluid, 

 the plant or cell sap ; by sectioning we may find the thick 

 leaves of the bulb made up of cells like those in the film. We 

 will carefully examine the mount with a first-class one-fifth or 

 one-eighth objective. We very plainly see the protoplasm along 

 the partition walls, much of it in the ends of the cells and an 

 occasional band crossing through the cells, usually obliquely. 

 We look in vain for the coveted streams ; we see the granules 

 trembling, vibrating and moving about in limited areas, but no 

 currents ; we examine the specimen all over from side to side, 

 and through the middle we plainly see the protoplasmic jelly in 

 every cell all in silence ; we wait and watch ; an hour has passed 

 away, we begin to see here and there little signs of motion, but 

 no streams. Why ? What is the trouble ? Our onion seemed 

 to be one of the best ; we are studying it in a temperature of 

 50°-t0° F.; we wait and watch patiently and carefully; the 

 midnight hour is here, we are at length rewarded with some 

 streaming protoplasm in the perfect border cells, for in the 

 wounded cells the protoplasm has already separated and rolled 

 together in a mass in the middle, but it is in only one or two of 

 the outer rows of cells that we find the protoplasm streaming, 

 all the inner cells are yet nearly motionless ; but weariness bids 

 us retire for rest, so we place this slide in a damp box, i. e., two 

 tea saucers inverted together, a little water in the bottom, the 

 slide supported on chips above it and thus leave it for future 

 study. 



In the morning we have an opportunity to take up the study 

 of our specimen ; the temperature of the damp box where it 

 passed the night is now 45° ; the protoplasm is streaming mag- 

 nificently ; we plainly see it with a half-inch, and it can be seen 



