ZOANTHARIA 27 



thick-walled capsules have a distinct basal part to the spiral thread and are somewhat broader at the 

 one end. They are about 19— 24/i long and of fairly common occurrence. 



Both polyps from the colony taken in the Ofjord at Iceland differ from the main form with 

 regard to the nematocysts of the mesenteries. On maceration, namely, besides the above-mentioned 

 nematocysts, some egg-shaped capsules occurred, partly larger about 22 yt long and 19 « broad, partly- 

 smaller, about 14 /u long and n^ broad, both kinds being fairly numerous. On a closer examination 

 of the rather bad sections of this form, I found however, that these egg-shaped capsules do not lie in 

 the filaments but inside these, though it is possible that such a foreign capsule may lie in the filaments. 

 It is at any rate probable, that these nematocysts, just as was the case with some similar capsules in 

 E. incrustatus , do not belong to the animal but are foreign capsules absorbed by it (see p. 13). It is 

 worth observing, that the abnormal specimens of £. iiicrusfatus and E. erdmanni originate from almost 

 the same region. 



The species is dioecious. 



Remarks: I have here taken Zoanthus arcticus as synonym to E. erdmanni, though I have 

 not been able to prove the correctness of this assumption, no type-specimens of Z. arcticus being present 

 seemingly in the Bergen Museum. On the other hand, there are some specimens taken by Daniels- 

 seu in Komagfjord and determined (by whom?) as Z. arcticus. As far as I am able to see from the 

 anatomical examination these are no other than E. erdmanni, though they form no colony but are 

 single specimens. According to the rules of priority, the species should be called E. arcticus and not 

 E. erdmanni, if the supposition is correct that they may belong to one species. As type-specimens 

 seem to be wanting, however, and the description of Z. arcticus is fairly poor, it seems advisable to 

 retain the name E. erdmanni. 



Danielsseu states, that E. erdmanni occurs in two forms different as to colour, the one being 

 darker and the other lighter grayish. Several specimens may even be quite grayish, as e.g. those 

 from Altenfjord, but otherwise their external appearance does not differ much from that of the others. 

 On the other hand, from the localities mentioned below there is a more slender form, which in other 

 respects also differs a little from the main form. This variety has been named var. aurivillii, though 

 it hardly differs essentially from the main form, grading into this through some transitional forms. 



E. erdmanni var. aurivillii. 



PI. 2 figs. iS, 28, 29 PI. 5, fig. 5. 

 Zoanthus Couchi Johnst. C. Aurivillius 1886 p. 52. 



Occurrence: Norway Outer part of the Kwsenangfjord 50 — 100 fins. Stone and clay. June 

 1884 Carl Aurivillius, several specimens Ups. M. 



Finmarken Goes & Malmgren R. M. some specimens. 



Jagfjord 200m. 18. 2. 1899. Nordgaard 1 colony. 



Dimensions: Length of the largest polyp: 17 cm., greatest breadth 0-4 cm. 



Colour light grayish, in the distal end reddish (Aurivillius) in alcohol: light grayish. 



External appearance: the polyps are either separate, or form colonies connected by a small 

 tube-shaped ccenenchvme as in the main form. The number of polyps in the colonies is variable, the 



