ACTINIARIA 



63 



imen shows the following dimensions: Length of the column 1,5 cm, breadth 0,25 cm, length of the tentacles 

 about 0,25 cm (Carlgren). 



Occurrence: Sweden, Bohuslan: Gullmarfiord. Flatholmen on the base of .^/cyom'MW-colonies 



(Carlgren), Smedjebrotten on stones overgrown with Sertularia (Carl- 

 gren), Valbyfiord on the base of Alcyonium-colom&s (Aurivillius). 



Further distribution. S.W. Coast of England. Petit Tor and Orestone in the vicinity of Tor- 

 quay. South Devon: Tenby South Wales, in the ebb-zone in cavities 

 bored by Saxicava. Plymouth. 



Exterior aspect: The body is extended, almost cyhndrical and divisible into two regions, sea- 

 pus and capitulum. Gosse states that a well developed physa is also present. I formerly (1892) adopted 

 tliis opinion, mainly on basis of the description by Gosse. This so-called physa is, however, — as I after- 

 wards have found out — to be interpreted otherwise, and the more so as also Gosse mentions that the most 

 proximal part of it is sometimes furnished with a cuticle. If we more closely examine the iigure of Gosse 

 (1856, PI. 9, figs. I, 4) which was to represent the animal with expanded physa, we find that the scapus- 

 cuticle, above the cuticle-lacking most proximal part, forms some distinct, tranversal folds. The presence 

 of these strong folds does not indicate a normal appearance of the proximal body-end, but is rather to be 

 interpreted thus that the "physa" (the most proximal body-end) is not turned out, but the cuticle is in this 

 part loosened and pushed upwards, whereby the above-mentioned folds are formed. The observations of 

 these species, made by me during a long stay at the zoological station of Kristineberg, unmistakably prove 

 this to be the case. The thing is that the animal very easily casts off its scapus-cuticle. This unfastening 

 of the cuticle takes place most easily and frequently in the most proximal part which is mostly in con- 

 tact with foreign bodies. A physa, at least in the proper sense of the word, therefore, to my mind, does not 

 exist. Besides this, the proximal body-end may expand more or less disc-like when the animal has cast off 

 the cuticle. The above-mentioned specimen altered its form during the time of observation in such a way 

 that, instead of forming a prolongated cylinder, it formed a low cone with enlarged base, attached to the 

 glass. The cuticle of the scapus is rugous, of ordinary- thickness and not incrusted. Also the distal part of the 

 scapus-cuticle is loosely connected with the ectoderm of the scapus and forms an almost totally free tube 

 into which the distal part of the animal can be drawn. Consequently the animal is able to contract much 

 more than M. loveni. The capitulum is short, without a cuticle, distinctly polygonal and with 8 rather strong, 

 longitudinal ridges which are, however, not as conspicuous as in M. loveni. The tentacles are 18 — 32 in 

 number, the largest number observed by Gosse was 28, by Bourne 32, I have not found any more than 

 26 myself. According to Gosse the arrangement should be 8 + 8 + 12, in fact they are arranged hexa- 

 merously as in M. loveni (6 -f- 6 etc.) in three or four cycles of which the fourth is verj- incomplete. The 

 tentacles are short, the inner longer than the outer ones. The oral disc is small, with distinct radii. The mouth 

 is placed on a high cone. The actinopharynx is short, with 8 longitudinal ridges and just as many longitudinal 

 furrows. Whether a small ventral siphonoglyphe is present I cannot determine with certainty as the ex- 

 amined specimens were not in every respect well presen-ed. Probably a siphonoglyphe is present here as 

 in M. loveni. 



