ANATOMY, HISTOLOGY, MORPHOLOGY, AND PHYLOGENY. Ech. 25 
given by Carpenter of IIolopus rangi. The relations of Holopus to the 
Larviformia of Wachsmutli & Springer are discussed, and it is pointed 
out that Holopus differs from them : (1) in being unstalked ; (2) in 
having arms that can be rolled up ; (3) in having no basals ; but it pro- 
bably had both basals and infrabasals at an earlier period, and therefore 
is not truly monocyclic. There only remains the tegmen in which it re- 
sembles them, in which, however, it agrees also with Hyocrinus and 
Thaumatocrinus. From a comparative consideration of the calyx-covering 
in Crinoids , it results that in all forms in which moveable portions of the 
arms take a part in limiting the body-cavity, the tegmen is also move- 
able, and covered with little plates or quite naked. In all Crinoids in 
which the body cavity lies in a firmly connected capsule, or true calyx, 
the tegmen is immoveable, and therefore readily contains larger plates, 
which, on account of the ambulacral vessels, are necessarily interradial. 
Hence, all large plates in the centre of the tegmen are not necessarily 
homologous oral plates. Holopus , with its firm calyx, reverts to the older 
type and retains oral plates throughout life, as a persistence of embryonic 
peculiarities. From these reasons, Holopus cannot be retained in the 
Larviformia , and the structure of the calyx is no hindrance to placing it 
with the Articulata. 
Holopocrinidce differ from all Articulata in having no demonstrable 
basals. In Encrinidce the basals are very rudimentary. In Extracrinus 
the basals are very much overgrown by the costalia, while in Cornatulidce 
this is carried to an extreme. In Holopocrinidce the reduction of the 
basals was concluded in the Lias, while in Cornatulidce they still persist. 
It is concluded that the Holopocrinidce are a family of the Articulata , 
appearing in the Dogger and persisting to the present, the natural posi- 
tion of which is near the Pentacrinidce and Cornatulidce. 
Janet & Cuenot enumerate a number of cases of Eckinoids with 
multiple genital pores. In spite of the resemblance to Palechinoids , the 
authors do not look upon it as an atavistic condition, but as an abnor- 
mality. Whatever the number of pores may be, the genital gland 
remains simple. 
The authors further discuss the extension of the madreporic pores out- 
side the madreporite. Echinocyamus pusillus has only one pore. On the 
other hand, a specimen of Arbacia punctulata is described in which the 
pores extend half way down the test in the madreporic interradius ; 
internally nothing was visible of these extra pores. The authors hold 
the opinion that the interradial plates of the apical system are basals and 
the radial plates terminals. 
Lambert (2) describes a specimen of Echinocorys vulgaris , in which the 
loft posterior ambulacrum is placed further back than that of the right 
side, owing to the presence of a supplementary plate on the left side, 
which touches the fourth (left posterior) costal (genital), and is similar in 
appearance to the other costals, bearing, like them, a genital pore. The 
anterior left costal is also elongated, and irregular in form, and divided 
by suture into two parts, of which the anterior is imperforate. The 
