200 42 



formed by the coalescing of two papillae, the seventh was mostly also slit in the end. — 

 The tail projecting behind the last papilla, had a length of up to 2 mm . 



The visceral mass which reached to behind the sixth papilla, was attached to the 

 wall of the body by a loose, felt-like connective tissue, and the different parts of the mass 

 were loosely connected by such a substance. 



The central nervous system was quite as before described (comp. 1. c. 1874. 

 Taf. XXXVIII, Fig. 17); the nerve cells had a diameter of up to at most (H4 mm . The long 

 N. opticus was in the latter part black pigmented; the larger diameter of the short-ovate 

 eye was 0'30 mm , the lens was dark yellow. The otocysts which were situated at the quite 

 short cerebro-pedal connective, had a diameter of (M2 mm , and were closely filled with oto- 

 conia of a diameter of up to - 016 mm . The club of the rhinophores with a large ganglion 

 at its base. 



The buccal tube is quite short. The bulb us pharyngé us is short and power- 

 ful, of a length of 5— 6 mm , by a breadth of 5— 6 mm , and a height of 3-5 — 5 mm ; its form 

 is as shown before (I.e. Taf. XXXVI, Fig. 14, 17; Taf. XXXVIII, Fig. 20, 21). The labial 

 plates which cover the thick praemandibular muscular mass anteriorly, join each other 

 above and below; they are lemon-coloured or reddish on the outside, in the mouth-slit 

 darker to dark brown; each plate, when spread out, measured 3 mm in length, 2 mm in 

 breadth, they were, as usual, formed of small scales or plates arranged in series, and 

 situated close behind each other, measuring in diameter about 0"007 — 0'009 mm (comp. 1. c. 

 Taf. XXXVI, Fig. 15 — 16). When the above mentioned strong muscular mass is removed, 

 the fore side of the powerful mandibles is laid free; they are yellow, below the hinge- 

 part reddish chestnut; their length was 3 - 25 — 3 - 6 mm , and the breadth of both together in 

 situ 4 mm , their vault in situ I'25 mm ; the thin masticatory edge was smooth, the form as 

 shown before (comp. 1. c. Taf. XXXVIII, Fig. 1). The supplementary oral cavities were quite 

 small. The cheeks anteriorly (in the region of the fore end of the tongue) and also the 

 palate are lined with a powerful, brown yellow, as it were, very fine-grained cuticle. The 

 erect tongue (comp. I.e. Taf. XXXVI, Fig. 17; Taf. XXXIX, Fig. 6, 7) of a height of la— 

 1.75mm an( } a breadth anteriorly of l - 25 mm was of the common form with light yellow 

 radula. At the anterior edge of the tongue 8 — 9 series of tooth plates were found, at the 

 somewhat sunk upper side 6 — 5 series; in the somewhat (downwards) sloping radula sheath 

 were found 24—26 fully developed series and three younger ones ; so the total number of 

 tooth plates was 38 — 41. The lateral plates of the foremost (oldest) series were much damaged, 

 and often torn away; posteriorly on the back of the tongue their number on either side 

 was ll 1 ). The yellow median plates had a height of up to 0'10 mm , by a breadth of 



The number of series of toothplates in the specimens before examined by me, was about the same, 

 viz. in B. arborescens 33—45, in B. digitata 39, in B. calcarata 41, and in B. excepta also 41. 



