1880.J NATURAL SCIENCES OF PHILADELPHIA. 115 



optic ganglia (fig. 1). The proximal olfactoiy ganglia (fig. Ic) 

 bulbiforra, the n. olfactorii not very long; the distal olfactory 

 ganglia inverse pyriform. The buccal ganglia (fig. Idd) ovoid, 

 connected nearly without commissure ; the gastro-oesophageal 

 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. PI. 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 (PI. XY, fig. 2), clothed with a 

 pale 3'ellow 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 ram (fig. 3), narrow at the inferior end, broader 

 at the supei'ior, and composed of simple, somewhat curved, erect 

 stag's (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 (PI. XV, fig. 6a) of the length of about 0.18-0.2 

 mm.-, more thickened and jellowish in the anterior margin, otlier- 

 wise colorless. At the outer side of these median plates is a 

 somewhat shorter and narrower plate (fig. 6&6), of yellowish 

 color ; in the posterior rows (PI. XIV, fig. 20) much broader. 

 The three succeeding plates brownish-j-ellow, hook-shaped, all 

 nearly of the same form and of the same but outwardly slowly 



' Alder and Hancock (1. c. part VI) also saw small optic gauglia in the 

 Triopa clavigera. 



