HYDROIDA.- BALE. 241 



REPORT ON THE HYDROIDA. 

 PART III. 



I. INTRODUCTION. 



IN this third and concluding Report on the Hydroida col- 

 lected by the " Endeavour " are enumerated all the species 

 observed (except two or three forms represented only by 

 very imperfect specimens), with their localities, and, in the 

 case of those not already dealt with, their synonymy and 

 such other notes as it is thought might be of interest. Under 

 the names of species which have been described in Parts I 

 and II will be found references to the pages of those parts 

 where they are treated of, with, in some cases, further 

 remarks on specimens observed later. 



Altogether sixty-four species or varieties are represented 

 in the collections, of which twenty-two species and four 

 varieties were considered to be new. All of these were 

 described in the two former Reports, except Sertularella 

 tasmanica, S. undulata, Sertularia pusilla, Nemertesia ciliata, 

 var. cruciata, Aglaophenia divaricata, var. cystifera, and 

 Cladocar pella multiseptata, which are the only new forms 

 described in the present Report. In two or three instances 

 the new material has enabled me to describe the gonangia 

 of other species of which the gonosome was previously 

 unknown. 



The following is a list of the species observed : 

 Order GYMNOBLASTEA. 



Family HYDROCERATINID^. 



Clathrozoon wilsoni, Spencer. 



Order CALYPTOBLASTEA. 



Family CAMPANULARIID^]. 

 Campanularia pumila, Bale. 



Family CAMPANULINID^. 



Thyroscyphus marginatus, Bale. 

 Thyroscyphus simplex (Lamouroux). 



Family HALECIID.E. 



Halecium flexile, Allman. 



