324 W. A. HASWELL 
the ‘ Vormagen’ (post-ventriculus) from which the caeca are 
given off. 
Malaquin (1893) designates the divisions ‘ gaine pharyn- 
gienne ’ (buccal chamber), ‘ trompe pharyngienne’ (pharynx), 
‘ proventricule’, and ‘ventrieule’ (ventriculus plus post- 
ventriculus). 
McIntosh (1908) describes the region as consisting of 
(1) pharyngeal cavity, (2) protrusible proboscis, (3) proven- 
triculus, followed by (4) a short portion which ends in a dilated 
region often with two lateral caeca (see Pl. 15, fig. 6). 
Il. Tur Buccat CHAMBER. 
This is the only part which becomes actually evoluted when 
the proboscis is protruded. It is a short chamber with a cuticle 
thinner than that of the outer surface : its wall in the ordinary 
retracted condition is thrown into a number of folds. 
Ill. THe Prarynx. 
The pharynx is a cylindrical tube, usually of considerable 
length, straight in the majority, sinuous or coiled in the 
Autolytidae and in Amblyosyllis. It has a greatly 
thickened cuticle, the thickened lining terminating abruptly 
in front in an entire, lobed, or denticulate edge. In front of 
this is a circlet of papillae on the surface of which open the 
numerous fine duets of the pharyngeal glands. In most cages 
the pharvnx contains a single triangular tooth (or rather 
stylet) with the hase embedded in its dorsal wall. This is nearly 
always situated at the anterior end, and is so placed that, 
when the proboscis is protruded, its apex projects freely in 
front. In some cases the single tooth is replaced by a paired 
crescentic group of several teeth (Odontosyllis), or by 
a circles (Trypanosyllis, Autolytus). 
The cellular layer of the pharynx in the anterior part of 
its extent is a simple epithelium complicated only by being 
perforated by the system of splanchnic nerves. Posteriorly 
it becomes greatly modified by the development of numerous 
gland-cells, so that it virtually assumes the character of 
