1912] Long: Living Eggs of Rats and Mice 117 
dep. sh. cell 
Fig. I. Assemblage of parts of circulation slide in position ready to 
be put together. X 1. 
a, d, holes which receive the tube supports (tb. sup.); b, c, holes which 
connect the ineurrent and outcurrent channels with the cell on the upper 
side of the slide; bolt hl., bolt hole; cap. tb., capillary tube; dep., depres- 
sion; in. ch., out. ‘ch., incurrent and outeurrent channels; Ir. sl., lower slide; 
sh., shelf; tb. sup., tube support; up. sl., upper slide. 
in which are ground and polished the cell in which the objects 
for study are placed, and the channels through which the fluids 
“are conducted to and from the cell. The cell is a circular, flat- 
bottomed depression about 130 microns deep and 13mm. in 
diameter, ground and polished in the center of the upper side 
of the slide. At its margin the floor is broadly rounded (figs. 
J and L). At one end of the cell a crescent-shaped area of the 
surface of the slide is ground down and polished so that it forms 
a shelf (figs. I, J and L, sh.) about 35 microns lower than the 
upper side of the slide and about 100 higher than the floor of 
or cell cov. gl. 
Ne 
ANNAN Fs EAA SANTANA 
WLLL << LLL 
Gut. ch. © b in. ne 
ML 
Fig. J. Longitudinal section of circulation slide taken along the dash 
line in figure I. X 1.. 
cov. gl., eover-glass; other letters as in figure I. 
