REPORT ON THE ANTIPATHARIA. 209 



Stomodamm. — The ectoderm of the stomodseum has au interesting structure, which 

 appears to approach the Actinian type more closely than that of any other species yet 

 examined, and is unusually rich in " Stiitzzellen." The surface of the layer appears to be 

 chiefly composed of epithelial cells, which taper below to a slender filament. The whole 

 of the middle portion of the layer is filled with a very large number of small oval or 

 elongate cells, which are apparently of the granular gland type. Each cell stains deeply 

 in hematoxylin, and under a high power reveals a double row of small round granules in 

 its interior. Slender fibres appear to extend from the base of this glandular layer to 

 the nervous layer of the ectoderm, and between them a number of hyaline gland (?) 

 cells occur. The small granular gland cells appear to vary considerably in length, but 

 usually have a similar diameter; here and there, however, a very large one occurs, similar 

 to those of Antvpothes dichotoma. 



Mesoglcea. — The mesoglcea is usually very thin and structureless, rarely exceeding 

 15 /a in thickness. It presents no features of special interest. 



Entoderm. — The entoderm usually varies from 14 to 20 /j. in thickness, but at 

 the base of a tentacle may be considerably thickened. The layer appears to consist 

 chiefly, in its thinner portions, of small cubical cells, which contain large oval nuclei. In 

 the thicker parts of the layer a number of oval or angular hyaline gland cells occur near 

 the base, each of which has a small round nucleus. Entodermal muscular fibres have not 

 been observed. The mesenterial filaments are elongate ribbon-like organs, each of which 

 is provided with a rounded dilation at its free extremity. Some of them are apparently 

 forked near the apex. As in other Antipathinae the shaft of the filament is clothed on 

 each side by entoderm, but the terminal dilation has the same structure as the ectoderm 

 of the stoinodaeum. In this portion the small oval granular gland cells are well 

 marked. 



No ova or spermatozoa have been observed in the majority of the zooids examined, 

 but in two instances what appear to be immature spermatic capsules have been found. 

 In such cases a narrow semicircular band of tissue is found in the lateral sections of the 

 ccelenteron, which at its two extremities is fused with a confused mass of mesenterial 

 filaments. The arched portion is situated just beneath the curved peristome and follows 

 its outline. This band of tissue contains a number of oval capsules, about 45 /a long 

 and 32 /a broad. The capsules are filled with a large number of small round cells, 

 each of which shows a variable number of nuclei. All the cells appear to be at a similar 

 stage of subdivision, and no cells in the resting stage were observed near the wall of the 

 capsule, as in other forms. 



(zool. CHAI.L. EXP.— PART lxxx. — 1889.) Llll 27 



