318 The Closing of the Wounds in the Larval Necturus 
a larva measuring 22 mm. was cut as above described and the movement 
of the gland cells followed. Their successive positions are represented 
in Figs. 1, 2, 3, and 4. In these diagrams the light colored oval area 
represents the excised portion. The positions of the epidermal gland cells 
are represented by the white spots while the dermal chromatophores are 
represented by the irregularly-branched black spots. Although the 
diagrams were made with the greatest care only approximate accuracy 
can be claimed. 
If Fig. 1 be examined it will be seen that the gland cells have during 
the short interval, some 5 minutes, between the time of excision and 
placing beneath the microscope, moved over the margin of the cut toward 
the median line while the dermal chromatophores have remained prac- 
tically stationary. Fig. 2 is a diagram from the same larva 30 minutes 
later. By comparing this with the condition represented in Fig. 1 it will 
be noted that while the gland cells pass toward the open part of the 
wound at approximately the same rate, there is considerable irregularity, 
e. g., the cell lying between Nos. 1 and 2 has passed more rapidly toward 
the median line than either 1 or 2. The same is true of the gland cell 
lying just posterior to No. 8. Certain other peculiarities are noted, such 
as the appearance of gland cells Nos. 11 and 12, which were not visible 
in the preceding stage. By comparing any two gland cells bearing 
numerals, it will be seen, however, that they in general maintain the 
same relative distances from each other. 
The position of the gland cells about 30 minutes later is shown in 
Fig. 3. At the time it was impossible to represent the gland cells which 
came into the field of the diagram from the periphery, consequently 
those along the margin of the diagram have been omitted. If the posi- 
tions of cells Nos. 1 and 5 of Fig. 1 be compared with their position in 
Fig. 3, it will be seen that No. 5 has progressed more rapidly toward the 
center of the wound than has No. 1. In like manner No. 7 has passed 
more rapidly toward the center of the wound than has No. 2. While 
Nos. 4 and 10 have moved directly toward each other. Some of the cells 
have disappeared, as illustrated by the absence of one of the cells lying 
between Nos. 8 and 9, likewise, the cell lying just above No. 1. On the 
whole the diagram shows that the cells show a tendency to move toward 
the center of the wound and that in general they maintain their relative 
positions. 
Fig. 4 represents the position of the gland cells 30 minutes later. In 
the diagram, the cells at the periphery have been omitted as in the pre- 
ceding stage. The cells from the margin of the wound have continued 
