264 
J. STEPHENSON. 
glands.” Further forwards in the pharyngeal mass, dorsal 
to the - cavity of the pharynx, in what may be called the 
transition zone, the cells become sparser, and interlacing 
muscular fibres form the bulk of the mass. In this zone the 
cells are seen to change their characters as they are traced 
gradually forwards and inwards. They become rather smaller 
in size ; the deeply staining matter becomes less in amount, 
and is aggregated in smaller masses ; and the cell-body 
becomes continued into the now abundant fibrillar strands 
between the muscle fibres. Numbers of such cells can be 
seen, which, with still a considerable amount of deeply- 
staining matter, dissolve at their periphery into the fibrillar 
or reticular packing tissue (“ Fullgewebe”) between the 
muscle fibres (compare PL 19, fig. 5, from P. hawayana). 
Still further inwards and nearer the pharyngeal epi- 
thelium the deeply staining matter disappears altogether, 
and the tissue passes into the abundant connective tissue of 
the deeper portion of the pharyngeal mass, which is absent 
from the more superficial region where the typical chromophil 
cells are aggregated. The nuclei, no longer obscured, 
become conspicuous ; the nucleolus diminishes in size, and 
ultimately disappears ; the chromatin grains are distributed 
more evenly through the otherwise clear nucleus. But even 
quite near the pharyngeal epithelium occasional cells are 
still met with which retain the characters of those in the 
more superficial parts of the mass. 
In this deeper region the nuclei appear to undergo a final 
change by becoming smaller; maintaining the above cha- 
racters, they can be traced down to a size measuring 4 g in 
greatest diameter. Along with these, in the connective tissue, 
another type of nucleus is abundantly represented ; these, 
about 3 /x by 2 fx, are often irregular in shape ; the smallest ones 
stain darkly, and are almost homogeneous ; some appear 
clearer, with a few grains of chromatin. These I believe 
to represent the nuclei of the original connective tissue 
element of the muscular dorsal wall of the pharynx. They 
are similar to connective tissue nuclei elsewhere, and, as will 
