428 
THE VOYAGE OF H.M.S. CHALLENGER. 
coats are thin, excejit on the lateral processes, where a considerable depth of hypoderm 
exists. The circular muscular layer is feebly developed all round. The longitudinal 
dorsal form two powerful sausage-sha23ed masses which have a deep symphysis in the 
middle line and a firm internal boundary. The ventral, again, are reniform, since the 
outer edge is reflected inward. A wide hiatus occurs between these muscles, the inner 
edges of which are bounded by the powerful oblique passing to their insertions in the 
circular coat outside the nerve-area. The latter lies external to the circular coat, and a 
round neural canal lies in the median line toward the upper border. Two capacious 
and much folded hollow organs lie over the area below the alimentary canal, and plaited 
masses occur superiorly above the latter. The ventral blood-vessel runs in the middle 
line below the alimentary canal. The latter is firm and. brownish, the external coat 
consisting of a chitinous layer, on which the somewhat compact glandular tissue rests. 
The glands form close parallel rows, so that when viewed from the inner surface the 
aspect is characteristic. The granular masses and folded organs in the upper region of 
the perivisceral cavity are probably connected with the reproductive apparatus. 
The form of the snout in this species somewhat approaches the SahelUdes 
angustifolicd of Grube, from the Philippines, but which Marenzeller has placed under 
Amphicteis, and extended its distribution to Japan. Both this and the Amphicteis 
philippinarum of Grul^e have a spathulate snout. 
Grube’s example was procured between the Crozets and Kerguelen. The number of 
the anterior segments in his example was seventeen, and the posterior forty-five. 
Amphicteis, Grube. 
Amphicteis gunneri (M. Sars.) 
AmpMtrite gunneri, Sars, Beskrivelser og Jagttagelser, &c., p. 50, Tab. xi. fig. 30. 
Habitat. — Trawled at Station VI. (off the Strait of Gibraltar), January 30, 1873 ; 
lat. 36° 23' N., long. 11° 18' W.; depth, 1525 fathoms; bottom temperature 36°’0, 
surface temperature 58° '0 ; sea-bottom, Globigerina ooze. 
The specimen is small and fragmentary, but corresponds with the ordinary examples. 
The inferior curves of the hooks, as figured l)y Malmgren’s artist, are slightly at variance 
with nature, the posterior depression being too long, while the anterior convexity is 
correspondingly shortened. 
In the alimentary canal is a little greyish mud containing somewhat large Glohi- 
gerincB and a few sponge-spicules. 
1 Annelidenfauna d. Philippinen, p. 206, Taf. xii. fig. 1. 
