136 THE CRINOIDEA CAMERATA OF NORTH AMERICA. 
a small branch horizontally at a short distance from the disk. In another 
specimen of that species (Plate IV. Fig. 17), in which the tube is broken above 
the arms, it was replaced by another, which starts off somewhat obliquely 
from the top of the stump. A tube ina similar condition was observed in 
a specimen of Lobocrinus pyriformis, but there the recuperation made but 
little progress, for the new part did not attain one third the width of the 
old tube at the point of fracture. In the specimen of Macrocrinus jucundus 
(Plate IV. Fig. 15), a small branch starts from the tube close to the calyx, 
while in another specimen of our collection a branchlet is given off near the 
end of the tube. In Fig. 12 of the same plate (Steganocrinus pentagonus), 
and in Fig. 11 ( Téleiocrinus umbrosus) a second tube was formed at the top 
of the disk, in the former occupying the median line of the posterior area, 
and in the latter directed slightly to the right. In the remarkable specimen 
of Eutrochocrinus Christyi (Plate IV. Fig. 13) all the arms of the right pos- 
terior ray, and the outer arm of both adjoining rays, were destroyed, and the 
break in the test was closed by irregular new plates, which support a con- 
spicuous second tube. A still more remarkable instance of recuperation is 
presented by a specimen of Batocrinus subaqualis (Plate IV. Fig. 10), in which 
an enormous tube breaks forth above the basals. It occupies the whole 
length of the dorsal cup, and involves the plates of the posterior interradius, 
as well as of the posterior ray, and even some of the arm openings. The 
plates bulge outward almost at right angles to the sides of the cup, and form 
the lower part of the tube. Fig. 9 has a very large opening between the 
basals leaning somewhat toward the anterior side, which we think performed 
the functions of the anus in that specimen. 
Passing now to the Inadunata Larviformia, it must be stated that, so far 
as observed, the anal x is unrepresented throughout this group (see Figs. 4, 
5, 6, and 19 of the preceding diagrams), and we know of no case in which the 
anal tube, where it exists, is supported by an inferradial. This is explained 
by the absence of interbrachial and interambulacral plates, and the position 
of the anus intermediate between the radials and orals, or piercing the latter. 
Pisocrinus,* Phimocrinus, and Symbathocrinus have a long slender tube be- 
* The tube of Pisocrinus was observed by Bather, and described by him in his late work on “The 
Crinoidea of Gotland,” Part J. p. 22). Tt rests upon the truncated limbs of the compound radial and the 
large simple one to the left; but not upon the two supported by the plate R’. Bather refers the proximal 
plate of the tube to the anal 2, although the plate rests, like ¢ in Hefenocrinus and Hybocrinus, wpon the 
radials, and takes no part in the composition of the cup. So also the corresponding plate in Symbathocrinus 
is a tube plate, and not an anal as we stated in our earlier writings. 
