8 Oosl. 
CCELENTERATA. 
organs, velum, and mouth. The medusa escapes before the spermatozoa 
are mature. The author endeavours to show that this form of medusa is 
primitive, not degenerate, and states his views of the probable origin of 
the medusae in the group. The gonangia of Allopora and Distichopora 
are then described, and their development traced. By the help of dia- 
grammatic figures of these structures, a comparison is drawn between the 
gonangia of the HydrocoralUnce and those of the Hydromedusce. 
Hardy (32) describes the structure of the ectoderm of the blastostyle 
of Myriothela phrygia , and the stages in the formation of the gonophore. 
He points out that the gonophore appears to be a curiously modified bud, 
and that the generative eloments pre-exist as small cells, having lodg- 
ment in the tissues of the adult, and travel into the abortive bud which 
’ is their place of final development. The structure of the endoderm is 
also fully described, and a short discussion given of the physiology of 
digestion in this form. 
Korotneff (46) finds a form of sporogeny in Cunoctantha parasitica. 
Maas (52) gives an account of the structure and development of the 
buds of Cunina. 
Melt.Y (56) gives an account of the anatomy of Spongicola fistularis , 
but he seems very doubtful whether there is only one or more species of 
this interesting genus to be found at Naples. 
McMurrtcii (53) describes the development of Cyancea arctica. Seg- 
mentation is regular, and a blastula is formed. A solid planula is pro- 
duced by the immigration of cells. After swimming about for some 
time the embryos settle down and inclose themselves in a cyst. In this 
stage the solid endoderm becomes hollow. The mouth is formed, and 
then four tentacles make their appearance. Mesenteries are not formed 
until eight tentacles are acquired. 
VanuUffkn (74) finds that, contrary to the statements of IIa3ckel, the 
gonads of Turritopsis armata are interradial, not perradial, in position. 
I'urrilopsis belongs to the Margellidce i since it has solid, not hollow, 
tentacles, as in the Tiaridce. 
VaniiOffen (73), in giving a brief description of some observations on 
, the anatomy of Periphylla Jiyacinthina , asserts that it possesses solid 
tentacles, and suggests that this genus has relations both with tho Stauro- 
medusce and with Nuusithoe. 
VaniiOffen (75) proposes a new classification of the Authomedusce. 
The two main groups in his system are : I. The Codonulee i in which the 
gonads are not disconnected, forming a circular mantle round the gastric 
cavity ; and ii. The Oceanidce , in which the gonads are four in number, 
or in four pairs, and interradial in position . 
Sculater (62) describes the nervous system and marginal papillae of 
the Lucernarian Ilaliclystus auricula. 
Ciiun (13) gives an interesting and exhaustive account of the anatomy 
of Stephanophyes superba , and discusses the relations of the family 
Stephanophyidcc i which he places between the Diphyidce and Haeckel’s 
JDesmophyidcc. The species is monoecious, groups of three or four male 
