154 Natural History Bulletin. 



the calicular openings are wide and the orifice seems to be 

 closed by the pecuHar sphincter-Hke muscle in the walls of the 

 polyps. 



Mesenterial filaments could not certainly be distinguished in 

 this species. I think it probable that they are wanting in both 

 R. fiabeUum and the species of Muricca studied. If they 

 aid in the process of digestion, as thought by some writers, 

 they do not seem to be essential to that process in Gor- 

 GONiD^, as they are sometimes either entirely wanting, or so 

 rudimentary as probably to be of little utihty. 



The ova are large and abundant in the species examined. 

 They seem to rest directly on the calicular walls and not to be 

 borne on pedicels as is usually the case. 



In some sections that I have the ova appear to be embedded 

 in a mass of cells from the endodermal lining of the calicle; 

 and in others the ova are not in the calicles at all, but are 

 situated in water-vascular canals which lead from the calicles. 



Some of the ova in specimens of this species have almost 

 reached the planula stage of development. I ha\-e wondered 

 how these planulae escape from the zoanthodeme. It does 

 not seem likely that they could pass out through the aperture 

 at the bottom of the gullet and thence through the mouth as 

 in the hard corals. 



In the specimen of Briareiini asbestinnni referred to on 

 page I02, the planula could be seen from the outside "deep 

 within" the tissues of the coenenchyma, which is slightly 

 transparent in this species. They could also be seen in places 

 just under the ectodermal investment of the zoanthodeme, as 

 if they were in some way burrowing out. Might they not 

 find their way to points near the surface by following the 

 water-vascular canals and then break through the ectoderm at 

 those points? 



CcENENCHYMA moderately thick and crowded with cells. 

 In this species and in Muricea sp. the coenenchyma presents 

 an appearance of greater vascularity and more active life- 

 processes than in the others. It contains a greater proportion of 



