164 CALIFORNIA ACADEMY OF SCIENCES. 
towards and around a small concave pit or groove in the outer edge of the epidermis 
(fig. 105). 
}. Interior to these taller cells are shorter and thicker cells, indicated asd in the 
above figure. 
Exterior to these, the regular and characteristic tubercula pubertatis cells 
proper are seen numerous unicellular glands, the same as the goblet cells of the 
epidermis. 
In addition to these glandular cells, I find at certain intervals a few sense cells 
opening out into the narrow pit or groove just referred to. They are everywhere very 
few in number, tall, narrow, with now and then the tip projecting through the cuticle 
into the shallow pit (fig. 105s.¢./.) There is not a continuous row of these cells, but 
here and there are found bunches of half a dozen cells, opening close together. They 
do not seem strictly parallel, but bulge and diverge in such a way that in sections, 
which show the common cells parallel, rarely more than one single sense cell is in 
view to any great part of its length. This, together with the small number of these 
cells, is undoubtedly the reason why they are frequently overlooked. 
In connection with these sense organ cells, I have re-examined the ventral 
papillee found in Argilophilus marmoratus, and I find that these structures are really 
nothing but tubercula pubertatis nature, or at least sense organs furnished with sense 
cells, a description of which will be deferred to a future paper. As a general con- 
clusion, I may state that the tubercula pubertatis are really sense organs, furnished 
with sense cells of the same nature as those found in other parts of the epidermis, and 
described by me in Benhamia, and by Vejdovsky in Rhynchelmis, by Cerfontaine 
and Langdon in Lumbricus, by Hesse in Lumbricus and Allolobophora, ete. 
Septa. The septa are not all of the same thickness, neither is each individual 
septum of the same thickness throughout. The first distinct septum is found between 
iv/y. It is of regulation thickness, or as thick as septum x/xi and those following 
posteriorly. The anterior septa increase in thickness forwards and backwards in such 
a way that septa vi/vil, vii/viii are of about equal thickness, while those in front and 
behind these are thinner in proportion as they are more distant. The anterior five 
septa are much thicker in their central area, and thin out towards the periphery and 
-body-wall, but even then, at the thinnest part, they are about four times thicker than 
the posterior septa. The six anterior septa do not strictly correspond with the seg- 
ments, but are attached to the body-wall about one-fifth the distance forward from the 
posterior intersegmental groove. 
Suprapharyngeal and septal glands. The glandular mass superposed on the 
pharynx and opening into it, is prominent, but situated far back, and with its lobes 
pointing forward, or in the same direction as the septal glands. The opposite is gen- 
erally the case, and has been so in all other species examined by me. 
Longitudinal sections show that the regular septal glands are present in three 
somites. The most anterior pair is in iv, immediately behind the suprapharyngeal 
glands, and not separated from the latter by any septum. The other two pairs are in 
yand vi. In longitudinal sections the suprapharyngeal glands are seen to be com- 
