ANATOMY, HISTOLOGY, MORPHOLOGY, AND PHYl.OGENY. Ecll. 29 
Ludwig (5) describes the Morphology of Ilolothuriam under the 
following headings: — Cuvierian Organs, pp. 173-180; Sexual Organs, 
pp. 180-198 ; Blood-vascular System, pp. 198-223 ; Ciliated Organs of 
Synaptidce , pp. 223-229 ; Body Cavity, pp. 229-240 ; Supplement to 
Morphology, pp. 241-248. 
Under the Phylogeny (pp. 447-460), the author comes to the same con- 
clusions as in Ludwig (1). 
Ludwig (7) and Bartiiels have studied the anatomy of various Synap- 
tids , and find that in the adults radial water- vascular canals are wanting. 
Since they are present in the young, their absence must be due to 
degeneration, and supports the view that Synaptids are not to be 
looked upon as primitive. Semilunar valves occur in the tentacle canals 
of all the species examined, and otoliths are also present in all. The 
so-called eyes on the bases of the tentacles of S. vittata are, without 
doubt, sense organs. The bundles of fibres attached on the inner side of 
the calcareous wheels of Chiridota arise from a cushion of connective 
tissue common to the whole wheel-papilla, and consist each of six power- 
ful fibres, corresponding in number to the spokes of the wheel, and each 
attached to the concave inner side of the nave in tho angle between two 
contiguous spokes. In Myriotrochus the number of fibres is increased 
with the spokes. 
Perrier (1) concludes his memoir on the organization of Anted on 
rosacea and A. phalangium, giving an account of the absorbent canals, 
pp. 1-5 ; the arms and their cavities, pp. 5-19 ; the chambered organ and 
the cirrhi, pp. 19-29 ; the apparatus of irrigation, pp. 29-38, and the 
genital apparatus, pp. 39-63 ; and ending with a complete resume of his 
results, pp. 64-72. In an appendix a comparison of the author’s results 
with those of Hamann is given, pp. 73-77. 
Perrier (4) has studied the skeleton of the young Aster ias. The 
odontophores appear as interradial plates in the same meridians as the 
corresponding primitive interradials, with which they have nothing to 
do ; hence they form no parts of the primitive calyx, but could 
be compared to the orals of Crinoids. The author finds a similar 
development in the young Brisinga, in contradiction to his former 
statements ; the true primitive interradials in this species are micro- 
scopic, and fuse with the odontophore. The teeth at their first 
appearance form an integral part of the first ambulacral pieces. The 
first true adambulacrals correspond to the iuter^al between the second 
and third ambulacrals ; the last adambulacral is placed between the last 
ambulacral and the terminal. On the lateral aspect is a double series of 
marginals having a striking resemblance to Goniasteridce , Ar chaster id 'w, 
and Astropectimdcc. They have no definite relation in number and 
position with the adambulacrals. At the extremity of the arms is a 
semicircular terminal. The plates of the aboral region are arranged as 
follows (1) a large dorso-central ; (2) two plates well developed and 
distinctly interradial, and a third rudimentary ; (3) a circle of ten plates, 
five exactly radial, and five exactly interradial. The three plates of (2) are 
