XIII. SYSTEMATIC NOTES ON THE 



CTENOSTOIVIATOUS POLYZOA 



OF FRESH WATER. 



By N. Annandale, D.Sc, F. A. S.B., Superintendent of the 



Indian Museum. 



In preparing an account of the freshwater polyzoa for the 

 "Fauna of British India" I have had occasion to examine speci- 

 mens of most of the ctenostomatous species as yet known to occur 

 in the rivers, lakes and ponds of different regions. It may there- 

 fore prove useful to publish the following supplementary notes. I 

 have received much assistance in the preparation of specimens 

 from Mr. F. H. Gravel}', Assistant Superintendent in the Indian 

 Museum, and am indebted for man}' of these specimens to Dr. 

 K. Kraepelin, Dr. W. Michaelsen, Mr. C. Rousselet and Mr. R. 

 Kirkpa trick. Full references to literature on the Indian species 

 will be found in my volume in the " Fauna/' only a few of the more 

 important general works being cited in this paper. 



Suborder CTENOSTOMATA. 

 Division PALUDICELLINA. 



Ctenostomatous polyzoa in which the zoarium increases by a 

 cruciform^ system of budding, each zooecium giving rise normally 

 to three daughter-zooecia (one on each side and one at its anterior 

 end) and being connected posteriori}' with its own mother-zooecium. 

 No zooecium is ever connected by its base with more than four 

 others. In the polypide that part of the alimentary canal which 

 intervenes between the cardia and the main chamber of the stom- 

 ach is always more or less modified but never forms an organ of 

 compression or is provided with internal teeth. 



All the Paludicellina are found in fresh or brackish water. 

 Anatomically they appear to be related to the Alcyonellea rather 

 than the Vesicularina,^ to which many of them bear a certain 

 superficial resemblance. 



Family PALUDICElvLIDAE. 



Zooecia more or less tubular and at least partially vertical, 

 often adherent by the base only or altogether free. In adverse 



1 Rousselet {P.Z.S., 1907. (i), p. 252) refers to such forms as "Cruciform 

 Stolonifera ' ' but includes with them certain marine genera that do not exhibit 

 the same regularity in their method of budding. 



2 Waters, Joum. Linn. Soc. London — Zool., xxxi, p. 237 {1910). 



