546 OLWEN M. KEES. 



projecting into the ectoderm. A layer of foreign material is attached to 

 the outer region of the ectoderm. The mesogloea is a very thin layer, 

 being only one-quarter the thickness of the ectoderm. It becomes deeply 

 stained, is homogeneous, showing no fibrillar structure ; and is thicker 

 in places owing to the contraction of the body-wall. In structure it 

 appears to resemble C. ho'plites and C. myrcia, but in C. hoplites it is 

 about the same average thickness as the ectoderm. The mesogloea of 

 C. australis is also of considerable thickness. 



The endoderm of the column is much narrower than the ectoderm. 

 In this C. viridis differs from C. tnyrcia, where endoderm and ectoderm 

 are of about the same thickness. In C. viridis the endoderm becomes 

 thicker near the base. It consists of a spongy mass, and is not so deeply 

 stained on the whole as the ectoderm. In some places there are large 

 oval gland cells which contain a granular substance, these seem to be 

 more numerous in the endoderm than in the ectoderm. The endodermal 

 muscle is very feebly developed, but appears stronger in the base. 



There are no zooxanthellae present in this anemone, nor has their 

 presence been indicated in any of the other members of this genus. 



The sphincter muscle (Fig, 13) is endodermal, intermediate between a 

 diffuse and a restricted form, and is stronger than that of either C. australis 

 or C. myrcia. The mesogloeal processes are longer than those of C. myrcia 

 and are slightly branched. The muscle becomes much stronger towards 

 the upper part of the body. I have failed to recognise the simple cir- 

 cumscribed endodermal portion of the upper part of the sphincter as 

 described and figured by Haddon. 



The tentacles were described by Allman in 1846, and he was able 

 to recognise two kinds of nematocysts, the small oval nematocysts 

 which are very numerous and the large stinging cysts. Both kinds 

 have also been found in C. myrcia. The structure of the tentacle 

 (Fig. 15) is very much like that of C. myrcia ; the knobs consist 

 almost wholly of deep ectoderm ; the mesogloea and endoderm are 

 very thin, and the ectoderm consists of a mass of nematocysts, which 

 are long oval cells with the internal spiral coil showing perfectly. These 

 nematocysts did not stain, but appeared as highly refractive bodies 

 and are also present along the stems of the tentacles and in the ecto- 

 derm around the mouth. In C. myrcia the stems of the tentacles are 

 devoid of nematocysts, but they are found in the endoderm near the 

 tip of the tentacles in C. viridis ; they have not been mentioned as 

 occurring in the endoderm of any of the other members of this genus. 

 There is a distinct nerve layer at the base of the ectoderm, and that 



