BKANCHIOCERIANTHUS IMPEEATOR (aLLMAN). 251 



about 30 mm. from the base in a cliitinous sheath which gives 

 an anchorage to the Hydrozoon. With the exception of the upper 

 edge the sheath (Fig. 20 s) bears in most parts very numerous 

 hair-like processes (ap) of brown color, which are so entangled that 

 many foreign bodies {e.r/. Echinus spines, sand grains, dead 

 shells) are wrapped up within them. The sheath and the root 

 proper are united so closely that they are not to l)e separated from 

 each other without tearing. In contrast to the pink-colored 

 hydrocaulus the brown color of the sheath with its appendages is 

 very conspicuous. 



At the lowest end of the hydrocaulus the wall is very deli- 

 cate and has an opening, the margin of which is destitute of the 

 hair-like appendages. 



Above the root the mesoderm possesses here and there 

 irregular small depressions which are recognized by tolerable 

 magnification from the surface as clear spots. Tliese depres- 

 sions are also present in the wall of the root enclosed in the 

 sheath. 



A portion of the root cut longitudinally (Fig. 21) shows 

 that the sheath with its appendages is separate from tlie root 

 proper, but has an organic connection with it. The hair- 

 like appendage (ap.), which is seen to be a slender hollow 

 process of the sheath, embraces in its interior the thread-like 

 outgrow^th (o.) of the wall, which perforates the mesoderm and 

 is connected directly with the endoderm of the inner cavity of 

 the hydrocaulus. Hence it seems to me that the above- 

 mentional small depressions in the mesoderm are certainly the in- 

 dications of the wart-like processes of the wall of the hydrocau- 

 lus as in Corymorpha. 



