Anatomy of Gorgonid^. 115 



tributed along its length. Beneath the muscle is seen the 

 mesodermal plate of the mesentery. This is composed of 

 round cells with large nuclei. On the side of this plate oppo- 

 site the muscle is a layer of endothelium composed of quad- 

 rate cells with small nuclei. We have here a demonstration 

 of most of the points regarding the histological elements of 

 the mesenteries illustrated diagrammatically in fig. 6, PL II. 

 The mesodermal plate is seen to be covered on one side by 

 endothelium, and on the other by a muscle plate constituting 

 one of the retractor muscles. 



The o-astric filanieiits are attached, as in other species, to 

 the bottom of the gullet where the latter is joined by the 

 retractor muscles. These filaments hang down in many 

 convolutions to the bottom of the calicle. I did not get sec- 

 tions of this species which were favorable for the study of 

 these organs. 



The ova were very abundant. They are attached to the 

 inner edge of the mesenteries and seem to be about equally 

 distributed along these organs from a short distance below 

 the bottom of the gullet to the bottom of the calicle. The 

 ova are borne on slender pedicels which seem to spring from 

 the mesodermal plates of the mesenteries.' 



As is the case in most Coelenterates, there are no well dif- 

 ferentiated ovaries, their function being performed by certain 

 mesoblastic tissues. 



The ova are found in groups or bunches as is shown in fig. 

 5, PI. II, and several ova may be attached to one pedicel, 

 or perhaps it would be better to say that one pedicel may 

 branch one or more times so as to bear several ova. 



These clusters of ova sometimes almost fill the calicle below 

 the gullet, and present a beautiful appearance in sections 

 stained with carmine. In some instances, clusters attached to 

 adjacent mesenteries meet and apparently coalesce to some 



I "Amongst the Actinozoa, the ova are usually developed between the 

 epiblast and the hypoblast in walls of the gastric mesenteries." Compar- 

 ative Embryology. Balfour, p. 21. 



