x86 Transactions of the Royal Canadian Institute 



Dendr'onotus dalli (Bergh). 



Dendronotus dalli Bergh, Proc. Ac. Nat. Sci., Philad., Ft. I, 1879, p. 94; 

 Bull. Mus. Comp. Zool., Harvard, Vol. XXV, 1894. 



Body. — The body form is somewhat like that of the preceding species 

 but longer and more slender and not strongly marked off from the foot. 

 There is a considerable difference however in the dorsal papillae which 

 are not so high nor nearly so much or finely branched in any of the six 

 specimens I have examined. Also the first is separated from the rhino- 

 phore sheath and from the second by a relatively larger distance than in 

 D. arborescetis. The veil is present but not very strongly marked and 

 bears but three arbusculi on each side of which the outermost is some- 

 what the largest. A mediaji papilla is absent. The upper lip bears a few 

 small blunt subconical papillae. The rhinophore sheaths are quite large. 

 There were four pairs of dorsal papillae present save in one specimen in 

 which there was an additional pair but in all cases the posterior pair was 

 very small. The anal papilla lies between the first and second papillae, 

 i.e., about half way along the back of the animal and bears at its base a 

 small renal pore. The genital aperture lies just below and in front of the 

 first papilla on the right. 



Colour. — I have not examined this species alive but two of the pre- 

 served specimens were of a pale reddish brown with more strongly 

 coloured papillae. The others were of a dull indifferent grey. 



Dimensions. — The largest specimen measured, preserved, 31 mm. 

 long by 9 mm. high by 6 mm. wide which corresponds fairly closely with 

 the measurements given by Bergh. 



Head.— The head is small and has a more or less circular mouth 

 opening. 



Foot. — The foot is long and narrow, abruptly rounded in front and 

 with a distinct tail like prolongation behind. 



Rhinophores. — The clavus of the rhinophore is almost conical and 

 perfoliate but the leaves are not so deeply cut as in D. arborescens and it 

 bears from 12-15 leaves. The top of the rhinophore sheath bears four 

 or more usually five slightly dendriform papillae of which the posterior 

 is distinctly longer than the others — a character not marked in D. 

 arborescens. The sheath bears a dendriform appendage at its base on the 

 outer side. 



Cerata. — The dorsal papillae in this species are not nearly so much 

 branched nor are the branches so long or so fine as in the preceding 

 species. The posterior ones as already noted are very small and almost 

 unbranched. 



Radtila. — The narrow pale yellow radula bears a median line of teeth 



