HYDROIDA 



55 



From the reptant stolons proceed polyp stems up to 12 iimi. long, generally unbranclied; more 

 rarely 2—4 polyp stems proceed from a common trunk, 1—2 mm. high. The polyps attain a length 

 of 0.7 mm., and are fusiform, with 6 — 12 tentacles placed in a whorl. Below the tentacles the polyp 

 is surrounded by a pseudohydrotheca, which it is very difficult to observe on the pohp when whollv 

 extended. In general it is jellied and vigorously developed. The polyp stems are, particularly in their 

 proximal part, irregularly wrinkled. 



The very large gonophores show no medusoid structure; they are attached to the reptant sto- 

 lons by a short stem. 



Material : 



Greenland (Lille Hellefiskebanke) (the original specimen of Garvria grocnlandica Levin sen). 



An examination of the original specimen of Garvcia grocnlmidica .shows no difference at all 

 from Norwegian specimens of Perigoiiiiniis roscus. The species are no doubt identical. If we compare 

 Kramp's drawing of Garvcia gror)daiidica (1911, pi. XXV, fig. 6) with Jaderholni's figure of Pc- 

 rigonimus roscus (1909, Taf. IH, Fig. 7), there may, at the first glance, seem to be some points of 

 difference. Thus the stems of the specimen mentioned by Kramp are much .shorter. But this character 

 proves of little significance if we compare the sjDecimen with a larger colony, where, as a matter of 

 fact, the length of the polyp stems varies greatly. A greater stress might, on the other hand, be laid 

 on the apparently great difference between the pseudohydrothecae as represented in the two figures. 

 However, much depends on the contraction of the polyps and on the state of preservation, as is plainly 

 to be seen bv an inquirv into a larger material. I have several times had the opportunit\- of observ- 



(In 



200 m. 600 m. looo m. 2000m. 



Text-fig. R. The occurence of Perigonimiis roscus in the Northern Atlantic, 

 the hatched region the occurence accordintr to the Htterature is couiinou allthough scattered). 



