7. Anthozoa (incl. Hydrocorallia). A. Zoantharia. 19 



mesoglcea is a syncytium which entirely fills up the interior. Later this divides 

 into a peripheral portion which becomes the endoderm, and a central portion 

 which lies in the coelenteron (into which the stoinodieum now opens) and is 

 doubtless resorbed. The author also obtained several specimens of Semper's 

 second larva (Zocmthina, van Beneden), the smallest of which was 75 mm. and 

 the largest over 3 mm. long. They are ciliated all over but also possess a 

 girdle of stronger cilia. The siphonoglyph is distinctly seen in the stomodseum 

 of the largest specimen. The endoderm is not so highly vacuolated and does 

 not encroach upon the coelenteron to the same extent as in Zoantliella. In 

 the youngest stage there are 6 mesenteries but in several others there are 12, 

 6 large and 6 small. 



Havet has investigated the nervous system of Metridium dianthus, using 

 chiefly Golgi's method. The sensory cells are uni-, bi-, or multi-polar and 

 possess fine prolongations which constitute thin layers of nerve fibrils connected 

 both directly and by means of collateral fibrils so that each part of the body 

 is in intimate connection with the neighbouring parts. On these fibrils there 

 are also very small cells which are probably sensory cells in different stages 

 of growth. Near these sensory fibrils there are other nerve cells of larger 

 size but fewer in number, and probably wanting in the wall of the tentacles. 

 These are motor cells. They are usually multipolar and some of their pro- 

 cesses come into relation with the fibrils of the sensory layer, some appear to 

 terminate at the level of the muscle fibres. The nerve elements are found 

 in the endoderm as well as in the ectoderm and mesoglcea. 



Richet( 1 ) describes a method of preparation of an alcoholic extract of the 

 tentacles of Anemones. A toxic dose of this extract produces (in a rabbit) 

 almost sudden stoppage of the heart. The toxin e is not destroyed by boiling 

 the extract and it is distinguishable by its properties from any other animal 

 or vegetable poison. 



Nach Cerfontaine regenerirt sich Astroides nach Abschneideu des Oralendes 

 so, dass die Basalstiicke wieder zu normalen Individuen werden, die Oral- 

 abschuitte am proximalen Ende ebenfalls einen Kopf bilden. Ein einziger 

 Abschnitt regenerirte sich nicht, weil er mit der Schnittflache den Boden be- 

 riihrte, bildete aber ein dem normalen ahnliches Skelet. [Hentschel.] 



Alcock( 3 ) describes several new deep sea corals which have a very close 

 resemblance to species from the Sicilian and Calabrian Tertiary rocks. Several 

 species in this collection range across the Atlantic and into East Indian waters, 

 most of them also occurring in a fossil state in the Tertiary Deposits of 

 Southern Europe. Dendrophyllia (Canopsammia) profunda, discovered by Pour- 

 tales in deep water among the West-Indian Islands, is now found flourishing 

 in the depths of the Sea of Banda. The cosmopolitan Bathyactis symmetrica 

 illustrates elasticity of bathymetric range (289-1886 metres) as also do stephana 

 (69-1301 m.) and sibogae (522-1914 m.); Deltocyathus lens n. can accommodate- 

 itself with equal ease having been dredged from 390 to 4914 m. The 

 southern end of the Sulu Sea seems to be one of the richest places in the 

 world for deep sea corals. Three new genera are established: Lochmao- 

 trochus (1 n.) essentially a Conotrochus which forms small colonies by budding, 

 Githarocyathus (2 n.) which appears to connect Deltocyatlius and Nototrodius, 

 and Placotrochoides (2 n.) which connects Placotrochus and Platytrochus. The 

 author also describes Caryopliyllia 4 n., Ceratotrochus 1 n., Conotrochus 1 n., 

 Phlceocyathus 1 n., Cyathoceras 1 n. , Trochocyathus 2 n. , Thecocyathus 2 n., 

 Paracyathus 1 n., Deltocyathus 2 n., In. var., Odontocyathus 2 n., Stephano- 

 troclius 2 n. , Sabinotrochus 2 n. , Discotrochus 1 n. , Desmophyttum 1 n. , Fla- 



