264 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Ccelentera. 



Hypertrophy of Tentacles in Hydra.*— P. Schulze describes a 

 peculiar swelling of the distal ends of the tentacles in Hydra oliyactis, 

 which seemed to be a reaction due to the presence of swarms of the 

 hypotrichous Infusorian, Kerona pediculus. G. Entz jun. has recently 

 reported a degeneration of the tentacles due to Amceba hydroxena, but 

 the swelling in this instance was more irregular and less confined to 

 the tips. 



Siboga Plumularids.f — A. Billard reports on a collection of 71 

 forms, which include 26 new species and 19 new varieties. A number 

 of other species have not been seen more than once or twice before. 

 Many show a bathymetric distribution, varying from a score of metres 

 to six hundred ; Plumularia ventruosa was obtained from a depth of 

 1914 metres. A new genus, Hemicarpus, is established for species of 

 Lytocarpus, in which the phylactocarp forms a demi-corbula. 



Australian Hydroids.J — "W. M. Bale reports on a collection of 

 thirteen species, of which seven are new, namely, species of Campanu- 

 laria, Synthecium, Plumularia, and Aglaophenia. Most of the specimens 

 were collected from the Great Australian Bight. A noteworthy feature 

 is the robust character of some of the Plumulariaus, three of which were 

 fully 2 feet in height. 



Formation of Gonophore in Tubularia and Myriothela.§ — P. 

 Benoit has studied this much-discussed question in Tubularia indivisa 

 and Myriothela phryr/ia, and finds that the medusoid nucleus, or 

 " Glockenkern," has an endodermic origin. The genital cells arise from 

 the external epithelium of the manubrium, which is also, according to 

 Benoit, endodermic. 



Structure of Eudendrium griffini.j|— S. F. Light describes the 

 minute structure of this very distinct new species of Eudendrium from 

 the Philippines. Its most important distinguishing characters are the 

 large number of distally-directed tentacles, the long and slender 

 hydranth body, the small size of the hypostome, the presence of only 

 two male gonophores to a hydranth, and the deposition of ova on the 

 pedicels. The terminal hydranths of both male and female hydrocauli 

 are sterile, so that there are probably two types of zooids, nutritive and 

 sexual, or at least a distribution of function. In older colonies they are 

 attenuated and in various stages of degeneration. As a result of the 

 early atrophy of the female hydranths, the gonophores relax and allow 

 the ova to hang down beside the pedicels, in which their weight makes 



* Zool. Anzeig., xlii. (1913) pp. 19-20 (1 fig.). 

 + Siboga-Expeditie, Monogr. VIIa, Livr. lxx., pp. 1-114 (6 pis.). 

 % Biol. Results Fishing Experiments carried on by F.I.S. 'Endeavour,' ii. 

 Part 1 (1914) pp. 1-62 (7 pis.). 



§ Comptes Eendut,, clviii. (1914) pp. 888-91. 



|| Philippine Journ. Sci., viii. (1913) Section D, pp. 333-56 (2 pis. and 5 figs.)' 



