REPORT ON THE PYCNOGONIDA. 125 
of the legs, always been considered as a very important support for the beliet in the 
near relationship between the Pycnogonida and the Arachnida, and more especially 
the Phalangida. ; . 
Morphologically, the cesophagus extends from the mouth. to behind the cesophageal 
commissures.. Taking the function of the organs into consideration, I believe that only an 
extremely small part should bear the name of cesophagus. At a very short distance from 
the mouth the cesophagus widens considerably. This widened part, which shows its 
greatest dilatation in front of the middle of the proboscis, slopes again backwards, and 
imperceptibly passes over into a much narrower canal, which extends immediately 
behind the cesophageal commissures. The widened part of the cesophagus, which almost - 
reaches to the end of the proboscis, is invested by a chitinous wall. This wall is beauti- 
fully beset with thin parallel chitinous bands, which are furnished with numerous thin 
spines. In the front part these are wanting. They begin on the two ventral parts of the 
inside a little before they are found on the dorsal part. These foremost spines have the 
form of short teeth, and only further back do they assume the form of long thin spines 
or needles. From the wall of this ‘part of the cesophagus numerous bundles of trans- 
versely striated muscles extend till they reach the outer wall of the proboscis, their 
distribution bemg in Nymphon, e.g., such that two longitudinal rows are attached 
to each of the three parts of which the inner wall of the cesophagus is composed 
(Pl. XVIIL fig. 9). As to the function of this part of the cesophagus, judging from 
these muscles and from its internal armature, I think it not very hazardous to com- 
pare it with the cardiac portion of the stomach of the Crayfish. It is a masticating 
apparatus. 
Posteriorly it passes over into a very long (slender species of Nymphon), or rather 
short (Colossendeis) cylindrical tube, the wall of which is still divided into three longi- 
tudinal parts, which on a transverse section are triangular and leave an extremely narrow 
canal in their middle. I studied the histological structure of this part of the wall, which 
extends to beyond the cesophageal commissures. Its cells are of a long cylindrical form, 
longer in the middle and shorter on both sides of the triangular part. They are furnished 
with distinct nuclei, which sometimes are all placed near the outwardly directed extremity 
of these cells, but sometimes also are found more in the middle. Between these cylin- 
drical cells there are some of a long conical shape, the base of the cones being, as a rule, 
— directed outwards. Inside, the surface of these cells is invested by a structureless membrana 
intima, and outside a similar cuticular formation is present (Pl. XXI. fig. 6). This 
epithelial covering does not end abruptly immediately behind the cesophageal commissures. 
In the interior of the succeeding part of the intestine it forms three glandular bodies, 
which hitherto have not been observed, and whose function, judging from their position, 
must be, I believe, pancreatic. In fig. 7 on Plate XXI. I show the place occupied by these 
glands, and in fig. 8 of the same plate a transverse section near the extremity of the two 
