l6 ZOANTHARIA 



Colour: Brownish or gray in spirit specimens. Verrill gives the colour as "translucent 

 bluish or purplish-gray or grayish brown. The tentacles jjale orange or salmon with lighter tips. 

 The polyps more or less of a salmon colour". 



The external appearance has been well described by Had don and Shackle ton. The species 

 always forms large carcinoecia inhabited by Eupagurus pilosimanus. The coenenchyme develops on 

 the gastropod shell which it covers completely, thus forming some kind of shelter to the gastropod, 

 especially before its shell is dissolved (PI. i, fig. 8). The polyps are arranged in 2 groups an outer 

 con.sisting of a row of large polyps — 10 in the largest colony examined by me — and an inner one 

 consisting of a single, smaller polyp lying centrally on the ventral side of the carcinoeciura a little 

 behind the opening of the carcinoecium. 



The marginal polyps in contracted specimens are broader than long and elliptic in transverse 

 section. Some of the polyps on the sides of the carcinoecium seem to be larger than the others, some 

 smaller polyps occurring in the posterior region, though this is not always very ajiparent. Whether 

 such a small "posterior" polyp is of normal occurrence, as stated by Had don and Shackleton, I 

 am unable to say for certain, but it seems hardly to be the case to judge from my specimens. But 

 my materia] as well as Haddon and Shackleton's is too small to permit of any certain statement 

 on this jjoint, so that it may be left undecided, as also the question regarding the arrangement of 

 the polyp.s. As this species seems to have been taken in great numbers during the German deep-sea 

 expedition, I shall come back to this question later. 



Capitular furrows occur but are indistinct in the preserved specimens partially owing to the 

 irregular contraction of this region. 



The species is slightly iucrusted with foraminifera, mainly covering the polyps and the 

 neighbouring parts of the ccenenchyme. The tentacles are very small. 



The oesophagus is .short with a deep siphonoglyphe and a well-developed hyposulcus, which has 

 the same length as the oesophagus. 



Anatomical description. Haddon and Shackleton have given a good description of 

 the polyps of this species, but on several points their description requires supplementing. 



As stated l)y Haddon and Shackleton the ectoderm of the body-wall is discontinuous. 

 This does not apply liowever to the capitular region, especially its upper part, where the ectoderm 

 as usual is thicker than at the other places of the body-wall. If the ectoderm is still present, there 

 is in the upper part of the body-wall a fairly common occurrence of equally broad, thick-walled 

 nematocysts (length 24—26/^), but on the other hand no nematocyst capsules with greatly twisted 

 thread, which probably may be found in the lower part. Tlie mesogloea is very thick in comparison 

 with the ectoderm. It contains numerous but small cell-islets, which may sometimes be fairly 

 elongated and even form canals. In conformity with the often-quoted authors I have not been able 

 to find any connection between the ectoderm and the entoderm and these canals. Spool-shaped cells 

 also occur. 



The incrustation is inconsiderable and consists mainly of foraminifera together with .some 

 sand-grains. These lie in the ectoderm and in the outermost parts of the mesogloea. The entoderm 

 is thin and has almost the same size as the ectoderm. Haddon and Shackleton have given a 



