54 NATURAL HISTORY OF 



This species has been observed and described by 

 many naturalists, from Dujardin (1843) to the present 

 time. 



Mr. Gosse describes it, under the name of the 

 Slender Goryne, as " creeping irregularly in the form 

 of a white thread about the same thickness as a 

 human hair. This thread is cylindrical and tubular, 

 perfectly hyaline and without any vestige of rings or 

 wrinkles. The thread is very long in proportion to its 

 thickness, and here and there starts from its support 

 and sends off free branches, the ramification generally 

 forming an acute angle, and continuing of the same 

 form, structure, and thickness as before. The polyp 

 appears to be a clavate enlargement of the branch, no 

 open end of an investing tube being visible in any part 

 of the zoophyte. The head is transparent, slightly 

 tinged with yellow, corrugated with coarse annulations. 

 The form of the polyp reminds one of a familiar kind 

 of turnstile, or one of those presses the screw of which 

 carries arms loaded at their extremities with globes of 

 metal, to increase their impetus when turned.^' The 

 appearance described by Mr. Gosse is caused by the 

 4 capitate tentacles arranged like the arms of a cross 

 round the head. These tentacles are covered with 

 small tubercles bearing palpocils. At the opposite 

 extremity of the body, 4 false tentacles are placed at 

 right angles round the polypite. These are rounded 

 and serve as tactile organs. Mr. Hincks states that 

 Mr. E. W. H. Holdsworth succeeded in keeping alive 

 several specimens of the free gonozooid obtained from 

 the tanks in the Zoological Gardens, so as to trace 

 almost the entire course of the reproductive history. 



Prof. Allman, also, has carefully studied the anatomy 



