10 MATHILDE M. LANGE 
completely covered by epithelium. That the wound was 
actually covered by epithelium was proved by a microscopic 
examination of sections made of the piece in question. Another 
fact worth noting in this picture is the position of the two suckers 
at the obtuse end of the arm. These two suckers are somewhat 
drawn up as if they were also helping close the wound. ‘This 
abnormal position of the suckers, which I observed as a regular 
occurrence during the process of wound healing, pushes the 
section plane out of its original position (vertical to the brachial 
axis) toward the exterior side of the arm. The suckers con- 
tinued in this abnormal position for some time—in most cases 
from two to three days, in some cases ten days, and some even 
more. The same factors which cause the difference in time 
necessary for wound healing probably also play a part here: 
viz., location of the wound (distal or proximal), age of the animal, 
and season of the year. During my stay at Naples an octopus 
which measured a total length of 13 meters was placed in one of 
the basins of the aquarium. Before its capture the animal had 
lost the greater portion (about three-fourths) of one of its arms, 
thus placing the. wound in the proximal portion of the arm. 
The wound was completely healed and the two distal suckers 
were drawn up at the end in the abnormal position mentioned 
above. It required a period of three weeks before these suckers 
were again in their normal position. 
As soon as the two last distal suckers regain their normal 
position, the first sign of a beginning regeneration becomes 
visible in the shape of a little knob, lying near the external side 
of the arm (fig. 8). Figure 9 shows a more advanced stage, the 
knob has already developed into a small process. On the interior 
side of this process a little groove becomes noticeable. This 
groove is plainly seen in figure 10. The same picture also shows 
the formation of little transverse folds within the groove. These 
folds later develop into suckers. In the further course of regen- 
eration the folds take a form similar to little warts (figs. 11 and 
12). The cavity of the sucker and the adhesive part are formed 
later by means of invagination. The beginning of this process 
can already be noticed in the most proximal of the suckers shown 
