50 CTENOPHORES OF THE ATLANTIC COAST OF NORTH AMERICA 



Body miter-shaped, 70 to 115 mm. long. Lateral compression very 

 marked, the broad, lateral diameter being fully 3 times as wide as the 

 narrow diameter. The apical sense-capsule lies near the surface at the 

 bottom of a shallow cleft; it contains a spherical mass of lithocyst cells, 

 and is flanked on two sides by a row of branched papillae in the form of a 

 figure 8, the loops of the "8" extending around the pole-plate in the 

 plane of the wide, lateral diameter. The 2 excretory pores open on the 

 alternate outer sides of the pole-plate. There are 8 rows of ciliated plates, 

 each row containing 25 to 30 combs of cilia. These extend about three- 

 quarters the distance from the apical sense-organ toward the mouth. 

 The mouth is a wide-gaping slit and its cavity is of large dimensions, 

 comprising the greater part of the center of the animal. The entodermal 

 part of the stomach is small. There is no axial funnel-tube, but instead 

 there are 2 lateral tubes which extend upward from the funnel to the 2 

 halves of the pole-plate. Each of these tubes opens by an excretion pore 

 on alternate opposite sides of the figure "8 "-shaped pole-plate. The 

 funnel, or entodermal part of the stomach, gives rise to 4 interradial tubes 

 which bifurcate, giving 8 adradial canals, which in turn lead to the 8 

 meridional vessels that extend down the sides of the body immediately 

 under the 8 rows of ciliary combs. In addition to these meridional tubes 

 there are two lateral paragastric tubes which arise from the funnel and 

 extend down the middle of the broad sides of the animal. The 4 merid- 

 ional canals of each broad side are placed in communication one with 

 another by means of the oral forks of the paragastric vessels which extend 

 along the broad side of the mouth, but do not fuse with their fellows on 

 the opposite side to form a ring-canal. The 8 meridional canals are, 

 however, placed in communication one with another by means of a loose 

 network of numerous side-branches which anastomose through the 

 gelatinous substance of the animal, forming a wide mesh work. Some of 

 these branches join the 2 lateral, paragastric tubes, although never to 

 the extent observed in B. forskali of the tropical Pacific. These fusioiis 

 occur only in well-grown individuals of Beroe ovata, and distinguish this 

 species from Beroe cucumis of our northern waters, where no anastomosing 

 of the side branches, or fusions with the paragastric vessels has been 

 observed. The young B. ovata can not be distingmshed from B. cucumis. 

 There are numerous small, stellate areas of dark brown and light rosin- 

 colored spots upon the 8 meridional vessels and around the mouth. These 

 spots are especially conspicuous in young animals. The network of anas- 

 tomosing vessels that arises from the meridional canals is of a delicate 

 pink. The gelatinous substance of the mature animal is of a translucent, 

 steely-blue color. In Florida the animal is dull-milky in color, but in 

 the colder northern waters, as in the Chesapeake Bay, it is highly colored 

 and the canals deep pink or reddish-brown. 



When 2.5 mm. long the animal is covered with large, stellate pig- 

 . ment spots of a dark brown and rosin-yellow color. The apical sense- 

 capsule is relatively very large and is flanked by 4 branched, ciliated 

 papillse. The 8 rows of ciHated combs extend only about half the dis- 

 tance from the apical sense-organ toward the mouth. When about 15 to 

 20 mm. long the animal is quite translucent. The 8 meridional vessels 



