ANATOMY AND PHYSIOLOGY. 
Coel. 13 
The marginal corpuscles of Actinia are certainly not eyes, though 
they are most likely sensory ; this function being, however, subordinate to 
their use as offensive weapons ; B^raneck. 
Effect of the electric light on various species ; Lacaze-Duthiers (2). 
Specimens of Hydra retired under piece of bark, preparatory to sexual 
reproduction ; Tight. 
In Millepora plicata young sexual cells are found in the ectoderm of the 
coenosarcal canals ; the ova have a stalk, which can be broken and re- 
generated. The maturation of the ovum is described ; the segmentation 
is indistinct. The embryo assumes the form of a solid blastosphere, and 
in this stage migrates into the gastrozooid ; beyond this it was not traced. 
The origin of the sexual cells supports the view that the ectoderm of 
Hydrozoa is the original seat of the sexual cells; Hickson (2). 
In Myriothela the formation of the egg, and of the male elements, 
the fertilization and the earliest developmental changes are described ; 
Korotnev (1). 
Oonactinia prolifera (Sars) reproduces by transverse fission. Bud-like 
tentacles appear rather below the middle of the body and form two rings. 
Then an oral disc and oesophagus develope, and the upper part separates 
by a constriction. Some general observations on asexual reproduction 
of Actinians are added ; Blociimann & Hilger. 
Weisrnanu’s view of the origin of the female sexual products of the 
Hydromcdusce is confirmed in the case of Podocoryne ; Ishikawa. 
In Manicina areolata the endoderm is formed by delamination ; the 
supporting lamella is secreted by both endoderm and ectoderm ; the fifth 
and sixth pairs of mesenteries develope as stated by Lacaze-Duthiers. 
The mesenteric filaments are ectodermal. In conclusion, observations are 
given on the origin of the Anthossoa, which is regarded as having been pro- 
bably from a hydropolyp ancestry ; Wilson, H. Y. 
Statements as to the time of sexual maturity of various species ; 
Lo Bianco. 
List of Ccelenterata in which parasitic castration has been observed ; 
Giard(I). 
For a few remarks on records of hybridity, see Suchetet. 
Segmentation and formation of larva of Lucernaria described ; also an 
abnormal individual of L. octoradiata ; Bergii. 
In Epcnthesis m l cradyi the hydromedusa bears upon each of its four 
reproductive organs a number of Hy droid blastostyles, from which 
young Medusa are produced by budding. This life history is quite 
exceptional, the bodies carried on the reproductive organs being true 
blastostyles, so that there is a recapitulation of larval stages without sexual 
reproduction; Brooks (2). 
In PhyllorTiiza punctata the ephyra has eight, the next stage twenty- 
four, the next sixteen, and the adult eight marginal bodies. If the 
umbrella is injured, marginal bodies appear between the newly-formed 
flaps. Crambessa mosaica migrates up rivers to deposit its young. A new 
brown variety seems to have superseded the blue, except in Port Phillip. 
Freshwater Hydroids of Australia resemble those of Europe, though the 
marine forms differ widely; Lendenfeld (7). 
