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SUMMARY OF CURRENT RESEARCHES RELATING TO 
and found that it exhibits a distinct Edwardsia-sta^ge in which the dorsal 
and ventral pairs of septa have their muscle-layer on the sides turned 
towards the median plane, while the muscle fibrils of the lateral septa 
are disposed on the same side as those of the dorsal septum. Of 
HexactinioB with a bilateral disposition, Gereactis aurantiaca was studied, 
along with other larvae of the biradiate type. An Edwardsia-stage was 
again detected. Boveri therefore derives Ceriantheae and Hexactiniae 
from Edwardsia-like forms. He believes the Cerianthus-tj^e to have 
arisen from an Edwardsia-like form by the appearance of new pairs of 
septa between the dorsal directive pair. Similarly, he finds in species 
of Halcampa illustrations of the transition from EdwardsiaB to Hexactiniae. 
For the various groups of Actiniae he proposes the following genealogical 
scheme : — 
Hoplophoria coralligens.* — Dr. H. V. Wilson gives a description of 
a new Actinian found in the Bahamas, which is, unfortunately, based on 
a single female specimen. After a short account of its anatomy, the 
author discusses the morphology of the stinging organs. At first sight 
they appear to be modified tentacles, but each organ is derived from a 
chamber which also gives rise to one of a cycle of tentacles, and the 
longitudinal musculature of the tentacles is ectodermal, while that of 
the stinging organs is endodermal. In position and essential structure 
the four stinging organs of Hoplophoria agree with the marginal sacs of 
Actinia mesembryanthemum, and the author regards the two structures as 
homologous. The ancestor of the new genus very probably had a circle 
of small sacs, but when the habit of living in a hole was acquired, 
certain of these sacs were transformed into large and formidable weapons, 
while the rest were lost. 
In many points Hoplophoria agrees with the Antheidse, but differs in 
the possession of only four marginal sacs, which are highly developed, 
in that only the six primary pairs of mesenteries reach the oesophagus, 
while only four mesenteries bear generative organs, but these several 
points have, it is argued, but little classificatory importance. 
* Studies from Biol. Lab. John Hopkins Univ., iv. (1890) pp. 379-87 (2 pis.). 
