CRYPTOPHTHALMUS. 37 



long as the body, its sides produced in large parapodial lobes which 

 fold over the back. Gill small, projecting backward from under 

 the shell on the right. Male orifice near the foot edge on the right 

 side in front. Female orifice in front of the gill, below the tubu- 

 lar anal opening. Dentition unknown. Type, C. smaragdinus 

 Leuckart. 



C. SMARAGDINUS Leuckart. PI. 6, figs. 29-36. 



The animal is beautiful emerald green mingled with light green 

 marking. The shell is 8 mill, long, covering the gills, and covered 

 by a delicate mantle-layer. It is fragile, thin, translucent, white. 

 The side margins are only slightly curved toward each other, with- 

 out whorls or columella. The two broad, thick, free lateral para- 

 podial lobes may be reflexed over the back, entirely closing over 

 the gill. The free end of the gill, similar to that of Aplysia, may 

 project behind the shell. Tentacles wanting. Head shield distinct, 

 raised, two-lobed behind. In front, above the mouth, there is on 

 each side a small eye, not visible in the specimens preserved in 

 spirit. The body on each side of the head shield and within the 

 parapodial lobes, has a series of short oblique folds. Ventral sur- 

 face more or less convex. Genital openings and anus as in Aplysia. 

 Length of body two inches. In alcohol they measure one inch. 



Red Sea at Tor and Suez ; Mauritius ; Reunion. 



Bidla smaragdina RUEPPEL & LEUCKART, Neue wirbellose 

 Thiere des Rothen Meeres (in Atlas zu der Reise im nordlichen Af- 

 rika von Eduard Riippell, Erste Abtheil. Zoologie), p. 26, pi. 11, f. 

 2 a-d (1828). Cryptophthalmus olivaceus EHRENBERG, Symbol* 

 Physicae, seu Icones et Descriptiones Animalium Evertebratorum, 

 etc., Decas prima, Mollusca, pi. 1, f. II A G. B. (Crypt.} olivacea 

 A. AD. in Thes. ii, p. 598, pi. 121, f. 56. Cryptophthalmus smarag- 

 dinus MARTENS, in Mobius' Reise nach Mauritius, p. 305. 



When contracted, the animal assumes a globular shape (pi. 6, 

 fig. 31, anterior view ; fig 30, dorsal view). In fig. 36, the lateral 

 lobes are separated. 



The nameless species mentioned by von Martens as being near 

 the genus Cryptophthalmus, in Beitrage zur Meeresfauna der Insul 

 Mauritius u. der Seychellen, p. 343, pi. 21, f. 7, is a Haminea. 



C. CYLINDRICUS Pease. PL 2, figs. 36, 37, 38. 



Shell unknown. Animal elongate, cylindrical, smooth, sides 

 nearly parallel. Cephalic disk short, about one-fourth the entire 



