Di.srorefij of a Sessi/e Coimhirifi . — JlnaileuKi mi . 67 
is seen from the inside. In both, the ring becomes attenuated 
toward the top (in fig. 2 abruptly) thus forming u skin which 
fastened the basal appendage to the pyramid. This skin 
formed a dome above the ring, as may be inferred from the 
laterally compressed specimen reproduced by fig. 9, at a: h is 
the basal ring, which on account of its bulging out a little 
more, adheres to the counter part of the fossil. The general 
form of the appendage may be compared to a bell, which term 
will be applied in this paper to the exterior chitinous wall of 
the organ under consideration, as the -word does not imply any 
expression regarding the possible functions of the whole. 
Fig. 10 reproduces a specimen (taken from the original to 
pi. VIII, fig. 2), which gives a view of the inside of the dome 
of the bell and exhibits irregular radial wrinkles of the skin 
caused probably by shrinkage prior to fossilization. In fig. 
12 a base is seen from above. Here the greater part of the 
ring is preserved, while the upper portion of the bell left only 
its impression. 
As appears from fig. 8, which reproduces the view allowed 
by one of the appendages into the bell from beneath, the lat- 
ter — or at least its thicker basal part — consisted of concentric 
layers. 
The absence of any carbonaceous film at the base of the 
bell (cf. iigs. 7, 8, 13) would lead to the conclusion that the 
bell was open there; but the smooth surface of the rock 
inside of the deeper impression of the ring (cf. fig. 9^7) in sev- 
eral specimens indicates the former existence of a basal 
closing film. A very clear view of the latter is furnished by 
the basal appendage (cf. fig. 15) of the Coiiularia reproduced 
in fig. II, which apparently was attached to a little fragment 
of a StictoporeAla. It appeared at first like fig. 15 ; the dis- 
solving of the enclosed rock, however, brought out the entire 
base of the organ, namely, the broad, deeply-impressed exte- 
rior ring {(i), the impression of the somewhat wrinkled film 
(6) stretching towards the center of the base and connecting' 
with an internal part (c) that appears as a narrower radially 
furrowed impression of a ring. The latter can be seen very 
distinctly at the bottom of the basal appendage reproduced 
by fig. 1. \w the remarkable specimen belonging to fig. 0, all 
cliitinous parts have been removed by weathering except two 
