PHARYNGEAL GLAND OF THE EARTHWORM aD 
he calls ‘ chromophile cells’, and the pharyngeal lumen. The 
function of these cells, according to this author, remains 
unknown. 
Of all the above-mentioned views, those of Eisen and 
Stephenson are specially interesting, as being diametrically 
opposed, though both based upon the study of the detailed 
structure of this organ. They deserve, therefore, to be examined 
in greater detail. 
Hisen (1894-6), in his series of papers on the Oligochaetes of 
the Pacific Coast of America, describes and figures the pharyn- 
geal or salivary glands of almost all the earthworms he studied, 
and especially those of the following five species: Phaenico- 
drilus taste (1894, pp. 66-7, Pl. xxx, figs. 1, 2, and 
Pl. xxxu, fig. 18), Pontodrilus Michaelseni (1894, 
pp. 77-8, Pl. xxxiv, fig. 36), Benhamia nana (1896, p. 129, 
Pl. xlvu, figs. 15-18), Sparganophilus Benhami 
(1896, pp. 104-5, PI. liui, figs. 112-13), and Sparganophilus 
Smithi (1896, p. 157). 
To demonstrate the views of this author, we shall quote from 
his paper the following descriptions which concern respectively 
the salivary glands of the first two species mentioned above. 
Phaenicodrilus taste (pp. 66-7): ‘The narrow 
ducts from the gland penetrate the pharyngeal epithelium and 
form, at its outer edge, small ovoid pockets for temporarily 
storing a small amount of the salivary secretion. These ducts 
end with the pharynx, the oesophagal epithelium neither being 
furnished with ducts nor storage pockets. . . .’ 
Pontodrilus Michaelsenti: ‘The duets lead directly 
to the pharyngeal epithelium ; arrived here they branch out, 
sending numerous discharge-tubes between the epithelial cells 
(fig 36, gl. dt.), discharging the salivary mucus in the pharyn- 
geal cavity. These ductules are frequently, though not generally, 
branched while in the epithelial layer. Hach ductule is 
furnished at the distal end with a small storage-chamber 
(36, A Pl. 34) of oblong form and considerably smaller than the 
nucleus of the epithelial cells.’ 
According to these observations, the pharyngeal cells, which 
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