382 On two rare British Nudihranchs. 



length when expanded. This is only half the length of 

 Mr. Hunt's specimen. Colour a purplish-rose, very similar 

 to the Dehsseria on wliich it lived. Too much stress should 

 not be laid on this point, however, since Mr. Hunt's example, 

 although apparently found on the same weed *, was olive in 

 colour. The mid-dorsal and lateral lines of the upper surface 

 darker. The epidermis of the upper surface is of a bluish- 

 green hue, as Gosse has already noticed {loc. cit. p. 317). 

 On the sheaths of the rhinophores are scattered bluish-white 

 spots; semilunar markings of the same kind occurred at the 

 base of the pleuropodial lobes (compare Trinchese^s figure of 

 Govia rubra). Body widest behind the head, gradually 

 tapering posteriorly. Head with an oral veil bearing four 

 papillai on each side, the second anterior one being the 

 largest. These papillae were constantly changing their shape 

 during life, as Gosse and Trinchese have recorded. Rhiuo- 

 phoral sheaths erect, cylindrical, the margin subdivided into 

 about ten rounded projections. This agrees closely with the 

 figure and description of the sheaths of Govia viridis. Those 

 of G. rubra, on the other hand, have plain margins. Rhino- 

 phores with a rounded, bulbous, laminated base, terminating 

 above in a smooth columnar tip. Pleuropodium produced 

 into four lobes on the right and five on the left, the fifth 

 being rudimentary. The first pair of lobes are opposite, the 

 rest gradually becoming alternate, as in Trinchese's figure of 

 Govia rubra. Each lobe is concave externally and is com- 

 posed of seven papilla?, one being dorsal and median, three 

 anterior, and three posterior. The foot is rounded anteriorly, 

 posteriorly it ends in a slightly bifid tail, as in Govia (Trin- 

 chese, loc. cit. p. 183 and my fig. 1). The anal papilla very 

 small, cylindrical, situated halfway between the tii-st and 

 second lobes of the right side. Genital opening near dorsal 

 surface between the rhiuophore and the first dorsal lobe of 

 the right side. 



In the apjjended table I have compared the difl'erent speci- 

 mens of lluncochia and Govia. Although they all agree in 

 main points, no two individuals do so in detail. 



• Gosse, loc. cit, p. 310, note. 



