264 SCIENTIFIC RESULTS OF THE 
optic ganglia (fig. 1). The proximal olfactory ganglia ‘fig. 1c) 
bulbiform, the n. olfactorii not very long; the distal olfactory 
ganglia inverse pyriform.. The buccal ganglia (fig. ldd) ovoid, 
connected nearly without commissure; the gastro-cesophageal 
ganglia small (fig. le), with one large cell. 
The eyes (fig. 1) with coal-black pigment and yellow lens.! 
The otocysts at the usual place on the under side of the cerebro- 
visceral ganglionic mass, crowded with otokonia of the usual 
kind (fig. 1). In the leaves of the rhinophoria no spicula; in 
the axes and in the stalk, on the’ contrary, spicula of the same 
kind as in the skin or often larger. The skin with few and 
small spicula and calcified rounded cells, here and there lying in 
groups. The marginal dorsal appendices covered all over with 
above-mentioned nodosities; at their points perhaps a similar 
(but empty) bag as in the typical species (Cf. Pl. XIII, fig. 16,17). 
The anal tube large, 3.0 mm. long. The bulbus pharyngeus 
strong, of the length of 4.0 by a height of 3.0 and a breadth of 
3.3 mm.; the radula-sheath projecting about 1.0 mm. from the 
hinder part of the under side of the bulbus. The lip-disk rather 
convex, with vertical oral slit (Pl. XV, fig. 2), clothed with a 
pale yellow cuticula, that behind the oral slit on each side is con- 
tinued in a triangular, brownish-yellow lip-plate of a greatest 
breadth of 1.0 mm (fig. 3), narrow at the inferior end, broader 
at the superior, and composed of simple, somewhat curved, erect 
staffs (fig. 4,5) about 0.18 mm. in height (fig. 4). The tongue 
broad; in the amber-yellow radula, thirteen rows of plates, 
further backwards in the sheath, six developed and two younger 
rows; the total number thus twenty-one. The three foremost 
rows of the tongue very incomplete, reduced to the outermost 
(four to five, six to seven, nine to eleven) uncinal plates. The 
rhachis rather broad, bearing two quadrangular thickenings of 
the cuticula (Pl. XV, fig. 6a) of the length of about 0.18-0.2 
mm., more thickened and yellowish in the anterior margin, other- 
wise colorless. At the outer side of these median plates is a 
somewhat shorter and narrower plate (fig. 60b), of yellowish 
color; in the posterior rows (Pl. XIV, fig. 20) much broader. 
The three succeeding plates brownish-yellow, book-shaped, all 
nearly of the same form and of the same but outwardly slowly 
1 Alder and Hancock (1. c. part VI) also saw small optic ganglia in the 
Triopa clavigera. 
