. Fig. 33. Amphiporus lecointei, Burger. A, dorsal, and B, ventral sides of the head. it ventrally there are several furrows passing forward upon the head (Fig. 33B). The opening of the head gland can sometimes be seen at the tip of the head: the larger opening of the rhynchodaeum is subterminal. There is a semi-lunar group of about twenty deeply embedded eyespots showing palely through the skin passing outwards on each side from the tip of the head along the margin and turning medially. Follow- ing these eyespots there is a deep closely-set posterior group of eyes behind the cephalic furrow o
. Fig. 33. Amphiporus lecointei, Burger. A, dorsal, and B, ventral sides of the head. it ventrally there are several furrows passing forward upon the head (Fig. 33B). The opening of the head gland can sometimes be seen at the tip of the head: the larger opening of the rhynchodaeum is subterminal. There is a semi-lunar group of about twenty deeply embedded eyespots showing palely through the skin passing outwards on each side from the tip of the head along the margin and turning medially. Follow- ing these eyespots there is a deep closely-set posterior group of eyes behind the cephalic furrow of each side (Fig. 33 A). The distinctive marking of the species is a broad brownish red band down the back extending on to the head. The edges of the body and the underside are uncoloured. Form and colour of preserved speci- mens. The stout body does not twist much. Often the ventral side is more convex than the dorsal and there is a tendency for the body to curl with the dorsal surface inside. Occasionally the ventral surface is flat or concave while the dorsal is humped. The proboscis is usually pro- truded. It is nearly the same length as the body. The colour can in some specimens be traced as a grey band. The eyespots are large. On clearing, the anterior group can be seen to consist of 10-20 on each side opening forward, the posterior of 16-18 opening laterally or posteriorly. Anatomy. The basement membrane stains somewhat with haematoxylin and is nearly as thick as the epithelium, which is itself very thick. Each of these layers is four to five times as thick as the circular muscles. The longi- tudinal muscles are thick and show a marked pennate arrangement of the bundles (cf. A. marioni, Hubrecht). There are subepithelial glands in the head confined to lateral tracts from the tip to just beyond the cerebral canals. These I propose to call cerebral subepithelial glands. They differ in appearance and staining reaction from the head glands and their ducts can be seen travers
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Keywords: ., bookcentury1900, booksubjectocean, booksubjectscientificexpediti
