HISTOLOGY AND DEVELOPMENT OE MYRIOTHELA PHRYGIA. 505 



On some Points in the Histology and Develop- 

 ment of Myriothela phrygia. 



By 



IV. B. Hardy, B.A., 



Shuttleworth Scholar of Gonville and Caius College, and Junior Demonstrator 

 of Physiology in the University of Cambridge. 



With Plates XXXVI and XXXVII. 



While working at the Marine Biological Laboratory at 

 Plymouth during the summer of 1888 my attention was 

 directed to the remarkable hydroid Myriothela phrygia. I 

 was acquainted with Professor Allmann's (1) memoir, and it 

 appeared to me that there were several points which demanded 

 further study — notably the development of the gonophore and 

 the structure of the endoderm, especially in relation to the 

 physiological processes taking place in the enteric cavity. My 

 work was continued, so far as circumstances would permit, 

 during the ensuing winter ; but on the appearance of Korot- 

 nefF\s account (2) of the growth of the gonophore, published in 

 the ' A.rchives de Zoologie Experimentale ' for that year 

 (1888), I discontinued it, in the hope that at some future time 

 I might find the opportunity of examining with something like 

 completeness the physiology of Myriothela. That opportunity 

 unfortunately has not arisen, and I am induced to publish my 

 results as they stand, believing that though incomplete they 

 contain certain points of interest. 



The first complete account of the anatomy and development of 



