4 6 



ANNELIDS. I 



apex which is bent, and under which is situated a strong spine. Along the edge of the end-blade are 

 found a few acute, obliquely placed spines, the largest of which is situated most proximally. The 

 shaft is noticeable on account of its strange thickness in proportion to the end-blade. 



The much longer and slender, capillary setae vary somewhat in shape and aspect in proportion 

 to their position; those which are situated most ventrally somewhat approach in shape the thick ones above 

 described ; their end-blade is distinct, even if it has grown long and narrow, and the tooth under the 

 apex is plainly pronounced; the edge is beset with rather strong spines (fig. b). The more dorsally 

 situated are markedly capillary; the end-blade is indistinct, the spines are few and feeble, and there is 

 no trace of a tooth under the tip. 



Alentia gelatinosa (Sars). 



1835. Polynoe gelatinosa, M. Sars: Beskr. og Iagtt. p. 63. 



1858. Halosydna gelatinosa, Kinberg: Freg. Engenias Resa p. 19. 



i860. Polynoe — , Sars: Chr. Vid. Selsk. Forh. p. 58. 



1865. Alentia — , Mahngren: Nord. Hafs-Ann. p. 81. 



1867. , Malmgren: Ann. polych. p. 14. 



1886. , Langerhans: Zeitsch. W. Z. Bd. 40, p. 251. 



1894. , Bidenkap: Norges Ann. polych. p. 62. 



1900. Halosydna , Mc. fntosh: Monogr. Brit. Ann. p. 384. 



Locality : 



The Faroe Islands; Auda-fjord, 16 — 32 fms. 



— ; North of Nolso c. 100 fms. 



— ; "Stokken" in d. e. 50 fms.. 



Onlv three specimens are present, all from the Faroe Islands a locality where, according to the 

 literature, this species could be expected to be found. It can be found, according to Mc. Intosh, 

 everywhere round the British coast; further it is known from Bahuslan in Sweden, from several Nor- 

 wegian fjords, and reaches so far southwards as Madeira, from where Langerhans communicates about 

 it. In spite of its rather great distribution it seems nowhere to be really common, if anywhere at the 

 British coast. 



As to the bathymetric distribution, I shall only remark that Mc. Intosh states that it can be 

 found in tide-pools, and that Ehlers notes it from a depth of 1336 fms. 



The species was originally described (1835) by M. Sars under the name of Polynoe gelatinosa, 

 later, Kinberg in his report on the Annelids of the frigate Eugenia, referred it to his genus Halosydna. 

 In 1865 Malmgren describes the animal and forms a new genus for the species, maintaining that in 

 many and essential respects it differs from the forms, essentially from the southern hemisphere, 

 with which Kinberg had made it generically identic. Of late, Mc. Intosh in his great Monograph 

 incorporates it under Kinberg's genus-name of Holosydna, and at the same time he gives a new- 

 diagnosis of the genus. Mc. Intosh prompts this by remarking, that "Kinberg in his description oi 



