514 PROCEEDINGS OF THE ACADEMY OF [1899. 



The animals were singularly beautiful and very active, creeping 

 and swimming rapidly, the latter movement somewhat resembling 

 the flight of an insect. The body is plump and prolonged back- 

 ward into a short tail, the tentacles and rhinophores large and 

 leaflike. The epi podia are ample and winglike. They arise from 

 each side of the neck at a moderate distance from the rhinophores 

 with a clear space between them, but are united posteriorly. The 

 ground color is bright pale green, with a border of lilac or pale blue 

 around the edge of the epipodia. The outside of the epipodia, the 

 head, neck, sides of the foot and upper surface of the mantle are 

 marked with black reticulations, to which are added black eye-like 

 spots on the three regions first-mentioned. The inside of the 

 epipodia is marked with large irregular blotches of vivid black, 

 which, in some specimens, almost form a network pattern. The 

 lower surface of the mantle is black, and there is a distinct black 

 spot at the end of the tail on the upper surface. The skin is 

 smooth; there are no warts or filaments, but the edges of the 

 epipodia are wrinkled. The spermatic groove, proceeding from 

 the right oral tentacle, is very distinct. The mantle communicates 

 with the shell cavity through a small tube. The shell is of a fair 

 size, but very thin, and almost entirely membranous, with only a 

 slight calcareous deposit. There is a large greenish ctenidium, 

 which is not entirely covered by the mantle and shell. In front 

 of it is the genital orifice. The opening of the opaline gland is 

 single. The anal siphon is large. The sides of the stomach are 

 set with 12-16 closely packed, brownish, horny plates. The jaws 

 are long and leathery, and each divided lengthways into two halves, 

 one blackish brown, the other white. The radula is composed of 

 numerous teeth, the rows and the individual teeth being both very 

 close together. The central tooth (fig. 26, right side) consists of 

 a basal plate with three cusps, of which the median is the largest; 

 the lateral teeth (fig. 26, left side) of a basal plate with a simple 

 long inner cusp and shorter outer cusp, without accessory denticles 

 along the margin. This form is retained even in the marginal 

 teeth, the two outermost only becoming vestigial. The length of 

 the specimen figured (in alcohol) is 75 mm. 



This species corresponds in many ways with Pease's description 

 of his Siphonota viridescens, but is much smaller and not at all like 

 his figure, particularly in the shape of the head. The coloration 



