PART I. GENERAL ACCOUNT 



he described the organization of this animal (Fig. \A). [The material has 

 been further examined by Dr. Eve Southward (1961) who has found that it 

 consists of some sixteen species belonging to at least four genera and two 

 families.] Thus because of the mixture of species, which Caullery did not 

 detect, and because of the bad state of preservation of some of the material, 



it was not possible for him to elucidate 

 the entire structural plan of Siboglinum, 

 and, until 1951 the position of this 

 genus in the animal kingdom was not 

 determined. In a classification pub- 

 lished in 1948, however, Caullery placed 

 Siboglinum after the classes Entero- 

 pneusta and Pterobranchia as an adden- 

 dum to the phylum Stomochorda ( = 

 Hemichordata), on the supposition that 

 its organization was similar to that of 

 this phylum. 



The second representative of the 

 class — Lamellisabella zachsi — was found 

 by P. V. Ushakov in 1932 in the Sea of 

 Okhotsk. The characteristic appearance 

 (Fig. 12?) of this tubicolous animal, 

 recalling that of the sedentary poly- 

 chaetes, led Ushakov astray and he 

 ascribed Lamellisabella to the family 

 Sabellidae, merely putting it in a 

 separate subfamily (Ushakov, 1933). A 

 few years later, however, Johansson 

 (1937, 1939) studied two incomplete 

 specimens of L. zachsi in sectioned 

 material and concluded that this animal 

 had nothing in common with the Anne- 

 lida, nor indeed with any other phyla, 

 and created for it a new class, which he called Pogonophora [Gr. -ndjywv— 

 beard, </>epaj — bearer]. Johansson described many features of the organization 

 and noted the 3-segmental nature of the body. Most of his conjectures turned 

 out to be in general correct, though his interpretation of the segmentation of 

 the coelomic cavities is no longer accepted. 



The publication of the work of Caullery and Johansson aroused lively 



В 



Fig. 1. The earliest illustrations of 

 Pogonophora. 



A - Siboglinum weberi in its tube. (After 

 Caullery, 1914.) 



В - The front end of the body of Lamell- 

 isabella zachsi viewed from the side and 

 somewhat ventrally. (After Ushakov, 

 1933). 



