ON THE DEVELOPMENT OF TUBULIPOEA. 73 



On the Development of Tubulipora, and on some 

 British and Northern Species of this Genus. 



By 



Sitlney F. Harnier, Sc.D., 



Fellow of Kiug's College, Cambridge ; Superintendent of the University 

 Museum of Zoology. 



With Plates 8—10. 



Introduction. 



The principal object of the observations described in the 

 present paper was to test tlie conclusion^ at which I formerly 

 arrived^ that a process of embryonic fission is of normal occur- 

 rence in Cyclostomatous Polyzoa. The process had already 

 been demonstrated in Crisia (15) and in Lichenopora (16)^ 

 and I am now able to show that the development of Tubuli- 

 pora^ takes place on essentially the same lines. In the course 

 of these observations it became apparent that the discrimina- 

 tion of the British species of Tubulipora had not been 

 characterised with sufficient precision. 



The satisfactory determination of the species of Cyclo- 

 stomatous Polyzoa is not an easy task. There are perhaps 

 few cases, even in this group, in which the synonymy is in a 

 more involved state than in the genus Tubulipora. Many 

 of the specific diagnoses which have hitherto been given are 

 based on immature specimens, or are for other reasons insuf- 

 ficient for purposes of identification, and the compilation of 

 unduly long lists of synonyms is for this reason undesirable. 



' A preliminary note (17) on this subject was published, in which the 

 genus appears as Idnionea. 



