308 Mtscellaneoics. 



each cell possesses in the direction of the stem two canaliform pro- 

 longations, one of which runs along the dorsal and the other along 

 the ventral lamina, diverticula the length of which is equal to or even 

 exceeds that of the polyp-cell. Both the polyp-cells and their 

 diverticula are connected with each other by numerous apertures in 

 the lateral walls bounding them, _so that the nutritive fluid con- 

 tained in them has free communication throughout the whole stock. 

 0. The polyps are seated in the marginal parts of the polyp-cells, 

 and exhibit the typical structure of those of the Alcyonaria. Of the 

 compartments surrounding the stomach, one is dorsally, a second 

 ventrally, and the other six laterally situated ; I designate them the 

 dorsal, the lateral dorsal, the lateral median, the lateral ventral, 

 and the ventral compartments. The polyps usually possess no cal- 

 careous spicules ; but these may occur at the lower extremity of the 

 protrusible part, and even on the tentacles, 



7. At the apertures of the polyp-cells the dorsal lamina of the disk 

 generally rises to form a cup or calij.r, the margin of which projects 

 in three, live, or seven teeth. If there are three teeth, these are 

 seated above the dorsal and the two lateral ventral compartments. 

 With five te'eth, the fourth and fifth correspond to the lateral dorsal 

 compartments ; and with seven teeth, these projections are also 

 situated over the lateral median compartments ; so that there is only 

 the ventral compartment to which no tooth corresponds, although in 

 rare cases a rudimentary one is present. The polyp-cells in course 

 of development at the margin of the disk have only two teeth, 

 which correspond to the lateral ventral compartments. 



8. In many, perhaps in all, lleniUce, these calycine teeth contain 

 hollow, simple diverticula of the compartments surrounding the 

 stomach, which lie outside the plumose tentacles, and remind one of 

 similar structures described by me in the genus FauicuUna. But 

 in the Rcnillcti these calycine tentacles, as I call them, very frequently 

 project freely beyond the apices of the calycine spines, and to a cer- 

 tain extent represent a second deeper-seated circlet of tentacles, so 

 as to produce conditions which remind one of those of the Poly- 

 actinia?. 



9. As in other Penuatulidiie, the s^jjta surrounding the stomach 

 contain viusculi protractores and retnictores. With regard to these 

 muscles I have recently ascertained, in the lienilhe, Veretillidce, and 

 Viryular'ur, that they are bilaterally symmetrical, and not arranged 

 in accordance with the radiate type. If a straight line be drawn 

 through the middle of the dorsal and ventral compartments in the 

 transverse section of a polype, each pair of protractors in one com- 

 partment are turned towards the straight hue, and in the other 

 turned from it ; whilst the retractors jiresent exactly the reverse. 

 This arrangement proves, better than any thing hitherto known, 

 that the Alcyonaria are hj no means regularly radiate creatures. 



10. The mesenteric Jilametits of the lienillce are as in the Penna- 

 tulida). The two long slender filaments are seated on the dorsal 

 septula, and run out into the dorsal diverticula of the body-cavity. 

 The four lateral septula have short and thick filaments, and lie in 



