54 : A. ©. OUDEMANS. 
other lacunz visible than the two above the cesophagus and on 
the sides of the proboscidian sheath. These gradually turn to 
one side a little, and come to lie in a fold of the cesophagus, 
which protrudes comparatively far into its lumen. Their 
proper lumen was filled with a coagulum that did not show 
any blood-corpuscles. Exactly the same coagulum here and 
there presented itself in little traces on the folds of the ceso- 
phagus, especially a little to the left and right of the median 
line ventrally, so that I am convinced that round the ceso- 
phagus the lacunar system occurs, though reduced to a mini- 
mum. The hindmost part of the cesophageal region and the 
rest of the body were absent. 
From another specimen I could examine some sections which 
were probably from the hindmost part of the cesophageal 
region. Here the cesophagus is surrounded by lacune. Above 
the cesophagus, at the sides of the proboscidian sheath, two 
larger ones were present. In the lacune surrounding the 
cesophagus here and there parts of the nephridial system were 
distinctly visible. In the lateral angles of the lacunz above 
the esophagus a longitudinal nephridial canal was distinctly 
to be seen lying partly in the longitudinal muscular layer. 
Everywhere the lacunz were richly coated by the epithelium 
that rested on a relatively massive layer of hyaline basal 
tissue. 
In both the specimens the vessel in the proboscidian sheath 
again showed the remarkable difference of structure in its dorsal 
and ventral half. 
In a third specimen, in which only the head and the fore- 
most half of the cesophageal region were cut sagittally, I 
convinced myself of the presence of even very large lacunz in 
this part of the cesophagus. 
12. Langia formosa (Hubr.), figs. 62—64. 
The vascular system corresponds to the type of that of the 
Schizonemertini. 
The aperture of the proboscidian sheath is nearly terminal, 
