23G MYKIOZOID^. 



Habitat. On shells of Pecten maxhnus. 

 Locality. Hastings (Miss Jelly). 



The cells are irregularly disposed ; but there is a ten- 

 dency to a radiate arrangement around the central part of 

 the colony. The crust varies much in form. In one spe- 

 cimen which came under my observation the colony con- 

 sisted of three or four parallel rows of immersed cells, 

 which are connected at intervals by crust and cells, so as 

 to form an anastomosing structure. Probably as growth 

 proceeded this would have been filled in and become a 

 continuous expansion, which is the usual condition of the 

 crust. In young cells the erect tubular portion is wanting, 

 and the peristome is very slightly raised. In the adult 

 the marginal spines are commonly absent, and when they 

 occur seem to be irregularly developed. Sometimes there 

 are two small spines in the centre of the upper margin, 

 and on each side a spinous process (projection of the peri- 

 stome) . The peristome is somewhat everted. Round the 

 base of the cell there are sometimes a number of indistinct 

 punctures. The ovicell is placed at the back of the 

 tubular neck below the aperture, and is very incon- 

 spicuous. 



This interesting species has only been found, so far, on 

 shells of the common scallop obtained from the Hastings 

 fishermen. 



Family XIII. — Myriozoidae (part.), Smitt. 



CELLEPORiDiE (part.), Johnston. 

 PoEiNiDiE (part.), D'Orbigny. 

 Membraniporid^ (part.), Busk. 

 MYRIOZOID.E (part.), Smitt, Kritisk Forteckn. 



ZoARiuM incrusting, or rising into foliaceous expansions , 



