10 EDWARD T. BROWNE. 



The occurrence of Periphylla at the surface in the Antarctic tends to show that 

 the " deep-sea " Medusas are lovers of cold water, or, at all events, flourish best at a 

 cool temperature. If the temperature of the water fixes their bathymetrical distribu- 

 tion, then we can account for their keeping below the warm water zones in the tropical 

 and temperate regions. I agree with Bigelow that the term " deep-sea " had better be 

 abandoned, as it is only misleading, especially as the 'Albatross ' obtained the majority 

 of the deep-sea genera within 300 fms. of the surface where the temperature was 

 above 427 F. 



Anatomical Results. In the Hydromedusau genus Koellikeria I have found the 

 interior of the stomach covered with minute endodermal papillre. Whether these 

 papillfe have the same function as the gastric filaments of the Scyphomedusse remains 

 to be found out. In the Antarctic species of this genus there are radial grooves in the 

 wall of the sub-umbrella, adjacent to the radial canals. The grooves are lined with 

 columnar ectoderm cells, and evidently from their appearance have a definite function. 

 The Mediterranean species (/ fascicularis) has not got these grooves. 



The new species of Sibogita has its stomach completely converted into a repro- 

 ductive organ when the gonads attain their full development. The stomach then 

 ceases to function as stomach, and its cavity is filled with endoderm. The gonads are 

 apparently in ectodermal pouches which are embedded in the endoderm, and the 

 pouches have openings to the exterior for the discharge of their contents. 



Classification. The revisions of the old genera and sub-families and the addition 

 of new genera which have come to light during recent years are gradually changing 

 the system of classification as laid down by Prof. Haeckel. Although improvements 

 have been made in some sub-families or groups, others still remain practically in their 

 old condition, mainly through the want of fresh material to work upon. 



By means of a new species of CataUeina in the Antarctic collections I have 

 endeavoured to show that the family Cladonemidse is no longer required. The chief 

 character which linked together the genera of this family is based upon the tentacles 

 having branches, or filaments, or stalked nematocysts. It has resulted in the bringing 

 together of a number of genera which have no true relationship with one another. The 

 character selected for the family is more suitable for a generic or even a specific 

 character. It is easy to abolish a family and to scatter the genera, but it is very 

 difficult at the present time to assign new places for them, as this involves revision of 

 other families or sub-families. 



A new genus (Cosmetirella) of Leptomedusse with open sensory pits led me to 

 examine other genera with similar organs, and I have collected them together under 

 the name of Mitrocomidee, and have defined the genera. 



A new species of the Margelidae raised difficulties over the old genus Itathkm. 

 As a revision of the species could not be satisfactorily accomplished without the use of 

 another generic name, I considered it is best to revive the generic name Koellikeria of 

 Agassiz, and thus to obtain a good type species. 



