CTENOPHORES OF THE ATLANTIC COAST OF NORTH AMERICA 23 
In the adult the body is oval, bluntly pointed above, and there is 
considerable lateral compression, the tentacular diameter being only a 
little more than one-half as wide as the transverse. The creature is 
about 80 mm.long. The aboral apex is quite blunt and the oral lobes 
are wide and about three-quarters as long as the remaining portion of 
Table showing the dimensions in mm. of specimens of B. vitrea from Tortugas, Florida, 
taken in June, 1910. 
Speci- Speci- Speci- Speci- Speci- Speci- 
men A, | men B. | menC, | men D. | men E, | men F, 
Total length of body............6.- 80 60 61 63 60 59 
Length from aboral apex to mouth... 58 49 40 43 36 39 
Maximum width in average expansion 
of the stomodzal axis ............ 46 39 oa 45 44 40 
Width of body in tentacular axis .... 23 22 22 24 ai 23 
Width across expanded lobes........ 38 45 52 39 40 38 
Length of auricles.............00055 20 19 16 16 15 15.5 
Depth of cleft of sense-organ....... 9 9 5 1 5.5 8 
Length of short rows of combs...... 37 28 23 28 at 27 
Length of long rows of combs....... 73 57 5I 47 4r 48 
Length of funnel-tube..............- 3 3 2 3 3 3 
the body. The apical sense-organ is situated in the bottom of a wide 
but not very deep cleft (text-fig. 6). The 4 auricles are edged by a linear 
row of ciliary combs, and arise from the sides of the body at a short 
distance above the mouth and close to the sides of the lappets. The 
lappets are flat and lanceolate and are each about one-fifth as long as 
the entire animal. The 4 subventral rows of ciliated combs are about 
twice as long as the 4 subtentacular rows. The combs of cilia are small 
and numerous, there being about 80 to 100 on each subventral row and 
40 to 60 on each subtentacular row. There is a row of short, simple 
tentacles on each side of the mouth, extending upward along the sides 
of the lappets to the bases of the auricles. The tentacle at the center of 
each row on the mid-axial line is longer than the others and is provided 
with simple, lateral filaments. The edges of the auricles are fringed 
with long, closely-crowded cilia. The stomodzum is long and narrow, 
and the funnel is short, being about one-fifth as long as the stomodzum. 
The chymiferous tubes are of fine caliber, and the windings of the merid- 
ional ventral tubes in the oral lappets are very simple, not complex as in 
B. infundibulum. The oral lappets are provided with a delicate network 
of longitudinal and transverse muscle fibers. The gelatinous substance is 
of very delicate consistency and is either transparent or diffusely tinged 
by a faint pink. The peripheral chymiferous tubes are of a more decided 
pink and in the lappets these tubes often display masses of intense pink 
color, probably due to products of digestion or excretion. 
When about 7 mm. long (fig. 16, plate 5), the body is oval with the 
two poles of about equal bluntness. Two long, flexible tentacles arise 
from the middle points of the sides of the body. These tentacles are 
highly contractile and give rise to numerous short, lateral filaments. 
They arise from the surface of the body and are not protected by sheaths. 
The apical sense-organ consists of a capsule containing a small mass 
of hyaline concretions. It lies at the bottom of a shallow depression. 
There is as yet no trace of the lappets, but the adjacent meridional sub- 
ventral tubes have fused, forming simple, closed loops. The 4 meridi- 
onal subtentacular tubes have joined with the circumoral vessel. When 
