19 Gcel 
C03LENTERATA. 
after Moseley’s researches, in Zool. Rec. xiv. Cosl. p. 10, it is only necessary 
here to add that the detailed investigation has only revealed points of 
structure closely analogous to those of Millepora and of Hydrozoa gene- 
rally. The calcareous substance of the “ hydrocorallum ” fills up the 
interstices of and is secreted by a dense anastomosing network of branch- 
ing coenosarcal tubes, radiating from and communicating with the bases 
of the zooids ; only in the older parts of the corallum the tubular system 
may be abortive and obliterated by the deposition of calcareous matter. 
Like others of the soft parts, the coenosarcal tubes are formed by an 
endodermal and ectodermal layer, and a separating basement membrane. 
The pigment-cells, to which the special colour of the coral is due, belong 
to the endoderm j the nematocysts, which are especially abundant on the 
dactylozooids and on the tentacles (if present) of the gastrozooids, or 
collected in groups or “ nematophores ” on the surface of the corallum or 
its projections, belong to the ectoderm ; those peculiar modifications of 
the endoderm, the gastric cells, are only found in the gastral cavities of the 
“gastrozooids.” Both sets of zooids are placed deeply in cavities with 
more or less narrow orifices. Muscles are found outside the basement 
membrane (in the ectoderm, accordingly) in the basal portion of the 
zooids, and continued down into the adjoining part of the coenosarcal 
tubes. The number 4 recurs in the cruciform mouth of many gastro- 
zooids, and in the number of main tubes radiating from the periphery of 
the base of the zooids ; the flabellate type of growth through buddiug, so 
common in Sertulariidce, &c., is also evident enough in many Stylasteridce. 
The gonangia are placed in closed cavities (ampullae), more or less pro- 
foundly, or in some instances prominently ; the gonophores are single, or 
few in number, in each gonangium ; the male gonophores contain a spadix 
and a sac with spermatozoa or spermoblasts ; the female a spadix and a 
single ovum. Sometimes the planulae or spermatozoa are set free through 
slits in the wall of the ampullae ; in other instances, probably, through 
its reabsorption. A special chapter is devoted to the genealogy ; of the 
known genera, Sporadopora is the most primitive, the nearest approxima- 
tion to Millepora^ &c. 
OTENOPHORA. 
1. Buekers, P. G. Bijdragen tot de Kennis der Anatomie van Cesium 
veneris^ Les. ; 66 pp. 1 pi. (Inaugural Dissertation). 
2. Chun, C. Die Greifzellen der Rippenquallen. Zool. Anz. i. pp. 
60-52. 
3. . Das Nervensystem und die Musculatur den Rippenquallen. 
Abh. senck. Ges. xi. pp. 181-230, pis. i. & ii. 
4. . Die im Golf von Neapel erscheinenden Rippenquallen. MT. z. 
Stat. Neap. i. pp. 180-218, pi. vi. 
Chun (4) distributes the Ctenophora in the following manner : — 
(A.) Tentaculata. 
1. Two long tentacles, simple or provided with lateral filaments. All 
