5^73 



Studies on the Hexactinellida. 



CONTRIBUTION I. 

 ( Bii2>lectelli(l(e ). 



By 



Isao Ijima, Rig., Ph. D., Rig.-Hak., 

 Prof, of Zoology, Imperial University, Tokyo. 



With Plates I-XIV. 



Introduction. 



Having devoted a great part of ray time for the last seven 

 years to the study of the Hexactinellida, I at first conceived the 

 idea of jiublishing all my results together in a single monograph, 

 and to some extent preparations were made with that end in 

 view. However, I have come to see that various unavoidable 

 circumstances have combined to make unpleasantly dilatory the 

 execution of tliat original plan. Let the work then appear 

 ill instalments as soon as the parts relating to this or that 

 group of forms shall have been made ready for i^ublication, I 

 will begin in the present commu' with the eight S2iecies, 



representing three genera, of t^- Euplectellida?, which 



have been studied by me. itipft- 



.iUN 2 1 1978 



