The Proboscis of the Syllidea. 
Part I. Structure. 
By 
W. A. Haswell, M.A., D.Se., F.R.S., 
Emeritus Professor of Biology, University of Sydney. 
With Plate 15. 
I. Divisions or THE Proposcis Recion. 
THE proboscis of the Syllidea (here taken as comprising 
all that part of the digestive tube lying in front of the intes- 
tine) is made up of five parts (fig. 6), which are all (with the 
exceptions presently to be noted) sharply marked off from 
one another. ‘These will be referred to here as (1) the buccal 
chamber, (2) the pharynx, (8) the proventriculus, (4) the 
ventriculus, and (5) the post-ventriculus with a pair of caeca 
appended to it. 
Ehlers (1864) recognized in the region (1) ‘ Risselrdéhre ’ 
(buceal cavity), (2) ‘Schlundréhre’ (pharynx), (3) ‘ Driisen- 
magen’ (proventriculus), and (4) ‘ Uebergangstheil’ (ventri- 
culus plus post-ventriculus). 
De Quatrefages (1865) (10, tome ii, p. 3) recognized buccal 
cavity, and pharyngeal, dentary, and oesophageal regions of 
the proboscis. 
Claparéde (1868) distinguished: ‘gaine de la trompe’ — 
(buccal cavity), * trompe ’ (pharynx), ‘ proventricule ’, ‘ ventri- 
cule’ with its glands (caeca). 
Hisig (1881) describes the ‘ Riissel6sophagus ’ as made up 
of three sharply-separated regions—the first (pharynx), the 
second (‘ Driisenmagen’), and the third, which he does not 
name, but which is the ventriculus: this is followed by 
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