The Atoll of Funafuti, Ellice group : its zoology, botany, ethnology and general structure based on collections made by Charles Hedley of the Australian Museum, Sydney, N.S.W.
Class Gephyrea. — Order Sipunculoidea. — Family Sipunculidæ
Physcosoma nigrescens, Keferstein.
Physcosoma nigrescens (Keferstein), Selenka, in Semper's Reisen. Arch. der Philippinen, iv., Die Sipunculiden, p. 72, pl. ix., figs. 130-136. There are two examples of this well marked species, both are well preserved and fully extended. In the larger specimen the body is 2 cm. in length, and the proboscis is about 2·2 cm.
Physcosoma scolops, Selenka and De Mann.
Physcosoma scolops, Selenka, Semper's Reisen. Arch. der Philippinen, iv., Die Sipunculiden, p. 75, pl. ii., fig. 17; pl. x., figs. 138-144.
Three examples of this species are in the collection. The largest example is 3 cm. in length, the large chitinous papillæ and the intense colour markings serve to readily distinguish this form.
Aspidosiphon elegans, Cham. and Eysenh.
Aspidosiphon elegans (Cham. and Eysenh.), Selenka, Semper's Reisen. Arch. der Philippinen, iv., Die Sipunculiden, p. 124, pl. i., figs. 10, 10a; pl. xiv., figs. 124 - 208.
One specimen, the body measures 3·5 cm., the proboscis is wholly retracted.page 394
Aspidosiphon steenstrupii, Diesing.
Aspidosiphon steenstrupii (Diesing), Selenka, Semper's Reisen. Arch. der Philippinen iv., Die Sipunculiden, p. 116, pl. i., figs. 12, 13; pl. xiii. figs. 190-192.
A single specimen is here doubtfully referred to this species. The body and proboscis are of a uniform pale brown colour, the anterior and posterior shields are darker, the latter is granular and radiately grooved, the former is slightly granular; an encircling series of about twenty small tubercles mark the line of union of the proboscis with the body.
The proboscis is clothed with a series of chitinous bodies of two kinds, those on the anterior half consist of flat curved bidentate hooks arranged in rings, each hook is about 0·05 mm. in height and 0·04 in width at the base. On the posterior half the chitinous bodies are scattered, they are elongate, three sided, slightly bent but not hooked at the summits, they are 0·04 mm. in height and 0·025 in width at the base. Numerous papillate skin glands occur between the rows of hooks, one to every four or five hooks.
The retractor muscles are 15 mm. in length, they are attached about 3 mm. from the posterior end of the body and are joined together at about 4 mm. from their point of attachment. The segmental organs are equal in length to the combined portion of the retractors, and are free from the body-wall for three fourths of their length. At the posterior third of the body there are twenty-five longitudinal muscle bands.
This form comes very near to A. speculator, Selenka, but the retractors are united much nearer the posterior end of the body, and the segmental organs are free for a greater distance than in Selenka's species.
Cloeosiphon aspergillum, Quatrefages.
Cloeosiphon aspergillum (Quatrefages), Selenka, Semper's Reisen. Arch. der Philippinen iv., Die Sipunculiden, p. 126, pl. ii. figs. 23, 24; pl. xiv. figs. 214-216.
A solitary example is somewhat doubtfully referred to this species. The specimen is 6 cm. in length, the proboscis is damaged and no hooks were available for examination. In other respects it agrees fairly well with the published description.page 395page 396