TENTACULATA 



153 



Bolinopsis in- 

 ( Mayer). 1, 

 oral lobe ; 3, 



Family 1. BOLINOPSIDAE. 



Oral lobes of medium size ; auricles short : 3 genera. 



Bolinopsis Agassiz {Bolina Mertens). With the characteristics of 

 the family; combs not prolonged onto the oral 

 lobes: 6 genera. 



B. infundibulum (0. F. Miiller) {B. alata 

 Ag.) (Fig. 250). Body up to 15 em. long, of 

 a transparent bluish- white color: from Vine- 

 yard Sound to Labrador, often very common 

 north of Cape Cod. 



Family 2. MNEMIIDAE. 



Lobes large, each bounded on each side 

 by a deep lateral furrow which extends to the 

 aboral end of the body; auricles long and 

 slender: 4 genera. 



Mnemiopsis Agassiz. Auricles long and 

 large ; combs prolonged onto the lobes almost to 

 their oral ends : 3 species. 



M. leidyi A. Agassiz (Fig. 251). Body up to 10 cm. long and very 

 transparent, at night very phosphorescent: Long Island and Vineyard 

 Sounds and south to the Carolinas, often in large 

 swarms; often parasitized by a sea anemone, 

 Edwardsia leidyi. 



M. gardeni Ag. Length 4 cm.; lobes rather 

 small and covered with warts; body translucent or 

 bluish in color: Chesapeake Bay to Florida; 

 abundant. 



Order 3. CESTIDA. 



Body flattened in the plane of the tentacles 

 and so enormously extended in the plane of the 

 stomach that it has the shape of a ribbon which 

 may be a meter or more long by 8 cm. high; 4 of 

 the combs (the subtentacular) are very short, the 

 other 4 are very long; tentacles more or less rudi- 

 mentaiy, tentacle sheaths deep : 2 genera. 

 With the characters of the order: 2 species. 



C. veneris Les. Venus' girdle. Body transparent, shimmering with 

 "\aolet, blue, or green : tropical seas, occasionally brought to our shores by 

 the Gulf Stream, fragments of the animal being occasionally seen on the 

 New England coast. 



Fig. 251 — Mnemiopsis 

 leidyi (Mayer). 1, au- 

 ricle ; 2, oral lobe ; 3, 

 mouth. 



Cestus Lesueur. 



