CTENOPHORES OF THE ATLANTIC COAST OF NORTH AMERICA 21 



This genus is closely related to Mnemiopsis, for Mnemiopsis in its 

 growth passes through a BoUnopsis stage. Phylogenetically speaking 

 Bolinopsis is simply an arrested form of Mnemiopsis , or Mnemiopsis an 

 advanced condition of Bolinopsis. 



Bolinopsis infundibulum. (Figs. 12 to 15, plate 4.) 



Springbrunner-Rotzfisch, Martens, 1675, Spitzbergische oder Gr5nlandische Reise- 

 besch., p. 12 1, Taf. P. 



Beroe ovata, Baster, 1762, Opscula subsecina, Bd. i, p. 124, Tat. 14, fig. 5. 



Volvoxberoe, Linn^us, 1768, Systema Naturae, ed. 12, Part 4, Corals, p. 910. 



Beroe infundibtdum, Muller, O. F., 1776, Zoologicae Danicae, Prodromus, p. 232, 

 Nr. 2816. — Fabricius, O., 1780, Fauna GrSnlandica, p. 360, No. 352. 



BoUna infu-ndibiiliim, Chun, 1880, Ctenophoren des Golfes von Neapel, pp. 293, 

 294. — ROmek, 1903, Fauna Arctica, Bd. 3, Ctenophoren, p. 78 (full list of 

 literature). — Vanhoffen, 1906, Nordisches Plankton, Ctenophoren, p. 5, 

 fig. II. — Browne, 1905, Proc. Royal Soc. Edinburgh, vol. 25, p. 784. — Evans 

 and Ashworth, 1909, Proc. Roy. Physical Soc. Edinburgh, vol. 17, p. 309, fig. 



Bolina norvegica, Vogt und Yung, 1888, Lehrbuch der Vergleich. Anatomic, Bd. 

 I, p. 170, Fign. 71-85. 



Bolina septentrionalis, Mertens, 1833, M6m. Acad, des Sci., St. P^tersbourg, Sci. 

 Math. Phys. et Nat., s6r. 6, tome 2, p. 515, Taf. 7, fign. 1-5. 



Bolina alata, Agassiz, L., 1849, Mem. American Acad., vol. 4, part 2, p. 349, 

 plates 6-8; also, i860, Cont. Nat. Hist. U. S., vol. 3, pp. 249, 289. — Stimpson, 

 1853, Marine Invert. Grand Manan, p. 11. — Packard, 1863, List of Animals 

 dredged near Caribou Isd., Canadian Naturalist and Geologist, vol. 8. — Agassiz, 

 L., 1865, North American Acal., p. 15, figs. 1-18. — Agassiz, A., 1874, Mem. 

 American Acad. Arts Sci., vol. 10, No. 3, p. 376, figs. 3-12. — Vanhoffen, 

 1895, Bibliotheca Zoologica, Heft 20, Lfg. i, p. 19. 



Alcynoe vermicular is, Gould, 1841 (non Rang); Invert, of Mass., p. 349. 



The adult (fig. 14, plate 4) is about no to 150 mm. long. The 

 aboral end is bluntly pointed and subconical, while the oral lobes are 

 large and rounded. Thus the general outline of the body is pear-shaped, 

 although the creature is compressed laterally. The lobes are about one- 

 third as long as the body of the animal. The apical sense-organ is placed 

 at the bottom of a deep, narrow cleft. It is very minute and contains 

 a mass of small, white concretions. The 4 subtentacular rows of combs 

 arise from the summit of the conical, aboral end of the animal and extend 

 straight down to the bases of the 4 auricles, which arise from the sides 

 of the animal at points about one-third the distance from mouth to apical 

 sense-organ. The subtentacular rows contain each about 35 to 40 

 combs, while the auricles are edged with a linear row of ciliary combs. 

 The auricles are flat and ribbon-like and about one-quarter as long as the 

 entire animal. The 4 subventral combs of cilia arise from the base of 

 the conical, aboral end of the animal and extend straight down to points 

 near the free, outer ends of the oral lobes. Each of these rows consists 

 of about 50 combs which extend about two-thirds the entire length of 

 the animal and reach a level lower than that of the ends of the 4 sub- 

 tentacular rows. The oral lobes are wide, rounded, and flexible and are 

 commonly folded so as to overlap on both sides of the mouth. Their 

 inner sides are provided with delicate longitudinal and transverse mus- 

 cles, the contractions of which enable the animal to compress the lobes 

 with considerable force, although not with sufHcient rapidity to be of 

 any appreciable service in swimming, this being accomplished almost 

 exclusively through the movements of the combs of cilia. There is a 



