On the 

 Morphology of the Enteropneusta.' 



PART I. 



By 



fVilliam Bateson, H.A., 

 Fellow of St. John's College, Cambridge. 



With Plates I— VI. 



In the ' Quart. Journ. Micr. Sci.' for April, 1884, 1 described 

 the early stages in the development of a species of Balano- 

 glossus, common on the shores of the Chesapeake Bay. I am 

 led from various reasons, which I hope to detail when an oppor- 

 tunity occurs for discussing the classification of the Enterop- 

 neusta, to regard this species as identical with that described 

 by Alex. Agassiz, and called by him B. Kowalevskii. 



I was again enabled, during the summer of 1884, by the 

 great kindness of my friend Dr. W. K. Brooks, to pursue my 

 investigations into the morphology of the Enteropneusta. My 

 warmest thanks are due to Dr. Brooks for once more affording 

 me the hospitalities of the Chesapeake Zoological Laboratory, 

 which was this year situated at Beaufort, North Carolina. 

 While there I collected a number of specimens of a large 

 undescribed species of Balauoglossus resembling B. salmoneus 

 (Giard). This species, a description of which will I hope shortly 

 appear, I propose to call B. Brooksii. My attempts at rearing 

 this species from the egg were unsuccessful, and I was pre- 



' A note on the subject-matter of this paper appeared in the 'Proc. Roy. 

 Soc.,' No. 235, 1885. 



1 



