j6 nudibranchiate gasteropoda. 



having moved down on the (right) side. The Doridoxidae form a transition to the Tritoniadae, a 

 connective link between the holohepatie and the cladohepatic nndibranehiata. 



The habitus of these animals is from the dorsal side quite like that of the Dorididae, in which 

 latter the branchial cleft was especially strongly contracted; but this cleft and the gill itself are 

 completely wanting, and the aims has moved from the dorsal side down on (the right) side of 

 the body. Ahead}- this characteristic gives them a resemblance to the Tritoniadae, which form the 

 outermost link of the Cladohepatica. And this resemblance is still greater by the fact that the strong 

 bnlbns pharvngeus is provided with powerful mandibles situated on its fore side as in the Trito- 

 niadae. Bv the presence of these mandibles 1 ) the Doridoxidae are otherwise nearly related to the 

 Bathydoridae, with which they also correspond with regard to the strnctnre of the radnla, this also 

 showing median tooth-plates, a featnre otherwise rather rare in the Dorididae. 



Hitherto the family contains only the genus 



Doridoxa, Bgh. N. gen. 

 and this genus contains only the one species, described below. 



Doridoxa Ingolfiana, Bgh. n. sp. 

 PL II, figs. 3-15; PL II,; figs. 1-3. 



One specimen of this species was taken in 1895 at a depth of 55 fathoms, at station 34, i.e. 

 on 65 c 17' Lat. N. 54° 17' Long. W. 



It was generally of a yellowish white colour, the back more whitish. The length was i2 mm 

 by a breadth of 7 mm and a height of 5 nim ; the length of the foot was io-5 mm by a breadth of 4 mm ; the 

 breadth of the head was 5 mm , of which breadth i-cj mm belongs to each tentacle; the height of the 

 rhinophores was i mm , the breadth of the mantle-brim o75 mm . The consistency of the animal was 

 rather soft. 



The intestines were nowhere to be seen from without. 



The form was oval, the hinder end a little more pointed (pi. II, fig. 3). The back was evenly 

 convex, anteriorly between the rhinophores it joined the somewhat projecting hinder margin of the 

 head; it was everywhere rather densely covered with small and quite small, semiglobular, and more 

 flattened papulee. The margin of the hollows of the rhinophores was slightly projecting, everted and 

 crenate; the (slightly projecting) club of the rhinophores was perfoliate; the dorsal brim was only a 

 little projecting, the margin rather sharp, the lower side smooth. The head was rather large, some- 

 what flattened, with a rather projecting hinder edge, a little produced on either side; with rather 

 large, rovmdish-lobelike tentacles; the outer mouth was round (pi. II, fig. 3). The sides of the body 

 are only Tow before and behind, otherwise rather high, quite smooth; anteriorly to the right is seen 

 the large genital papilla with the prominent little penis, and behind this the vulva (fig. 3); at the 

 beginning of about the last fourth part of the length of the bod}- was the projecting anal papilla, 

 and a little before this the smaller renal papilla (fig. 3). The foot was powerful, but narrower than 



M In several families of the cladohepatic group quite similar mandibles are seen, in Bornella, Scyllaea, Phylliroidae, 

 Pleurophyllidiadue and Pleuroleuridae. 



