PLATE L. 129 



Lougli, in 18(39. They were preserved in spirit in the 

 state in which they came from the eea. All of them 

 were parasitical on small fuci. The largest of them did 

 not exceed two inches in length, and the colour of all 

 of them was that of a dirty light green, with a tint of 

 light brown. In their wet condition they were soft to 

 the touch, and by no means attractive to the eye. 

 Two of them proved to be Isodictya simplex. On 

 mounting portions of the specimens in Canada balsam 

 their structural characters, as described in vol. ii, page 

 295, ' Mon. Brit. Spongiadoa,' were iu perfect accord- 

 ance with those of the type-specimen. 



