NOTES ON A DEEP-SEA ECHlUfiOID. 135 



Notes on a Deep-sea Echiuroid, Acantlio- 

 hamingia shiplei (n. g. et n. sp.), with Re- 

 marks on the Species Hamingia ijimai, 

 Ikeda. 



By 

 Di*. Iwaji Ikeda. 



With Plate 10. 



In July, 1909, I obtained au Echiuroid animal through the 

 kindness of Mr. Aoki, of the Marine Biological Station at 

 Misaki, Japan. As at that time the date of my departure 

 from Japan was near at hand I was compelled to bi'ing with 

 me the specimen, which remained untouched until the end of 

 October, when I entered the Zoological Laboratory of the 

 University of Cambridge. After some weeks' work in that 

 laboratory I discovered that this single specimen was a very 

 curious and undescribed species belonging to the Bonellidge, 

 and apparently to the genus Hamingia. Doubt was, how- 

 ever, thrown upon relationship of the new form to Hamingia 

 by two remarkable features, the presence (i) of the abnor- 

 mally numerous ventral hooks and (ii) of the skin-papillae. 

 The absence of the two structures just mentioned represents 

 the most essential generic characteristics of Hamingia, dis- 

 tinguishing the genus from the rest of the Bonellidge, 

 Bouellia and Protobonellia.^ Seeing many close rela- 

 tionships between the present species and Hamingia i j imai,^ 



' Ikeda, I., "Notes on a Xew Deep-sea Eclnuroid, Protobonellia 

 mitsiikurii,"' ' Annot. Zool. Jap.,' vol. vi. Part IV, 1908. 



- Ikeda, I., "On a New Eclnuroid (Hamingia ijimai) from the 

 Sagami Bay,"' ' Annot. Zool. Jap.,' vol vii, Part I, 1908. 



