. 228 DISCOVERY REPORTS brane and the muscles, and it has been traced forwards for some distance into the head. The lateral nerve stems are united by frequent commissural strands. From the trans- verse furrows between head and body the cerebral canals pass in on each side directly towards the brain. At the basement membrane ^ they meet and become embedded within a nerve from the dorsal ganglion (Fig. 4). The canal just penetrates the basement membrane but cannot be traced farther. These worms have been identified with Tubu- lamis nothus, described by Burger from the Mediterranean, from the for
. 228 DISCOVERY REPORTS brane and the muscles, and it has been traced forwards for some distance into the head. The lateral nerve stems are united by frequent commissural strands. From the trans- verse furrows between head and body the cerebral canals pass in on each side directly towards the brain. At the basement membrane ^ they meet and become embedded within a nerve from the dorsal ganglion (Fig. 4). The canal just penetrates the basement membrane but cannot be traced farther. These worms have been identified with Tubu- lamis nothus, described by Burger from the Mediterranean, from the form of the head, colour of the body and the arrangement of white rings, the pigmented patches of eyespecks, the side organs, and some anatomical features such as the ^ Tubulanus )l0thlis> Biirger. Section thickness of the epithelium and the position of showing the cerebral canal entering the the nephridial canals. The penetration of the nerve from the dorsal ganglion, e, epi- cerebral canals beyond the basement membrane thelium; cc> cerebral canal; #. dorsal , . .- T „ , ,. ganglion; Im, longitudinal muscles; vg, ven- is not considered of significance. In 1. banyulensis, *ral lion whose anatomy according to Burger (1895) is similar to that of T. nothus, the cerebral organ is a finger-like pit which reaches the basement membrane and is innervated from the posterior angle of the dorsal ganglion (loc. cit., p. 526). It is curious that T. annulatus was not taken at Saldanha Bay, for it was described by Stimpson (1856) from Simon's Bay near Cape Town. Order HETERONEMERTEA Genus Lineus, Sowerby Lineus bilineatus, Renier, 1804 (Plate XV, fig. 10). One specimen of this characteristically marked species was taken in August from a kelp root attached to a granite boulder on the outer shore near Eland Point—the end of the southern arm of the bay. The length was between 15 and 20 cm., but the specimen was damaged. The breadth of the head was o-6 mm. Eggs were present. Form and c
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Keywords: ., bookcentury1900, booksubjectocean, booksubjectscientificexpediti
