67 
these trials is to be preferred to even the slightest movement of 
the micrometer screw. It seems then not implausible that a 
connection really exists. I am thus disposed to assume that, being 
then widened the hairlike formation may act as outlets for the 
secretion. For a positive statement, however, new, and still better 
preserved material is necessary. 
Even if in cytological respect the real nature of the hair-like 
formations is not clear beyond doubts, there is hardly any doubt 
that by means of the secretion these cells function as adhesive 
organs. Having studied the adhesive cells of the Tricladida maricola, 
I have not the least hesitation in rejecting the interpretation given 
by Wilhelmi in his important work: Tricladen in „Fauna und Flora 
von Neapel“ and I must give full support to the view latest held 
by von Graff in Bronn (Tricladida), that the secretion passing 
through the adhesive cells really plays the role of adhesive sub- 
stance. Watching a triclad fastened to the substratum and beginning 
to tree itself before creeping starts, one becomes convinced that 
the visible muscular contraction detaches the animal from the 
substratum, 
It is true that the gatherings of coarse, clubshaped projec- 
tions from the adhesive cells of Triclads are impressive forma¬ 
tions, beside which the secretion rods of the Emprosthopharynx are 
rather diminutive, but for both kinds of cells it is valid that the 
secretion from giand cells in the parenchyma pierces the plasma of 
the adhesive cell. 
Lacking a sucker, Emprostopharynx has consequently as a sub- 
stitute the submarginal band of adhesive cells. To judge from the 
conditions in marine Triclads such a band might act excellently for 
its purposé. The broadness of the band, compared with that of 
marine Triclads, is noteworthy, even when regard is taken to the 
difference in size of body. The latter might more than counter- 
balance a possible disfavour in respect to effectiveness of the in- 
dividual cells in the Polyclad. 
The existence of this means of adhering must be of advantage 
to an animal taking up its abode with such an active creature as 
a Pagurid. But it might be mentioned that corresponding adhesive 
cells occur in the new species of Emprostopharynx from Gilbert 
Island (Apemama). This was found free-living. Being of an extremely 
5* 
