THE CTENOPHORA 



BoLixiDAE. Sagittal lobes of moderate size ; lobular canals simple ; 

 auricles short. Genera — Bolina, Mertens ; Bolinopsis, L. Agassiz ; 

 Hapalia, Eschscholtz. Family 3. Ueiopeidae. Body much compressed : 

 lobes of moderate size, with lobular vessels more complicated than in 

 Bolinidae ; auricles short ; costae comprise very few, but very broad 

 combs. Genus — Deiopm, Chun. Family 4. Eurhajiphaeidae. Two 

 wiiig-like projections at the aboral pole in which the sub-tentacular costae 

 and meridional vessels are produced. Genus — Eurhamphwa, Gegenbauer. 

 Family 5. Eucharidae. Lobes large, with complex lobula- canals ; 

 body covered with elongate touch -papillae ; a main tentacular filament 

 present, as well as accessory filaments ; above the tentacle bases are a 

 pair of openings which lead into elongate blind sacs lying in the sagittal 

 plane and ending blindly in the neighbourhood of the infundibulum. 

 Genus — Eucharis, Eschscholtz. Family 6. Mnemiidae. Lobes large ; 

 the lobes and auricles spring from near the level of the infundibulum ; 

 auricles long and ribbon-like. Geaera — Mnemia, Eschscholtz ; Alcinoe, 



Fio. IX. 



Ceshts veneris, Lesueur. m, mouth ; tsh, tentacle sheath ; cl, c*, c5, c8, the four ruJiinentary 

 sub-transverse costae ; c2, c3, c6, c'', the four large sub-sagittal costae ; sfl, sti, st^, s(S, the four 

 sub-transverse, meridional canals which communicate at xi, x2, with the sub-sagittal canals. 



Rang. ; Mnemiopsis, L. Agassiz. Family 7. Calymmidae. Body much 

 compressed ; lobes large, springing from the level of the infundibulum ; 

 costae nearly horizontal. Genus — Calymma, Eschscholtz. Family 8. 

 OcYROlDAE. Lobes of great length, with relatively small attachments to 

 the body ; costae horizontal. Genus — Ocyroe, 



Order 3. Cestoidea, Lesson. 

 Ctenophora so much compressed in the infundibular jilane as to be 

 band-like. The sub-sagittal costae extend over the whole length of the 

 aboral surface ; the sub-transverse costae rudimentary. The sub-transverse 

 meridional canals run down the middle of the band-like body and unite 

 with the ends of the long sub-sagittal and stomodajal canals. Tentacle 

 sheath and tentacle basis present, but no main tentacle ; accessory tentacles 

 lie in four tentacular grooves which extend, on the oral surface, from the 

 mouth to the extremities of the band-like body. Gonads developed only 

 in the sub-sagittal canals. Family Cestidae. Genera — Cestus, Lesueur ; 

 Vexillum, Fol. 



