170 SEA-SHORE LIFE 
larva with large rounded head, and lash-like tail. The larva usually 
breaks through the egg membrane and swims through the water, 
avoiding the hght. Soon, however, it settles down, and becomes 
fast to the bottom by means of the adhesive slime of its body. Often 
it becomes fastened by the tail, but occasionally by its head or some 
other part of the body. The little creature then struggles vainly 
to free itself for a time, but soon the tail becomes absorbed, the 
nervous system degenerates and the animal becomes a Ciona, fixed 
for life to one spot, and in its adult state no one would suppose 
that it was in reality a vertebrate. 
Molqula manhattensis, Fig. 119. This is found under stones, 
etc., below low tide level from Maine to the Carolinas. The body 
is about one inch in diameter, rounded 
in outline and usually covered more or 
less with particles of sand and detritus. 
In color it is dull olive green. Two 
long tapering spouts project upward, the 
uppermost being for the admission, and 
the lower for the discharge of water 
which passes through the gills. Alto- 
gether the creature presents the appear- 
ance of the water bottles made of skin, 
such as are still used in the Orient, and 
indeed the name ascidian signifies a 

Fig. 19; MOLGULA MannatT- ttle water skin. “The eggs are laid 
TENSIS. Woods Holl, Mass. a little before daybreak during the sum- 
mer months, and the larve develop in a 
few hours into little tadpoles within the egg membrane, and finally 
change into fixed tunicates without being set free from the egg 
membrane. 
This species may often be seen in the New York Aquarium, 
where colonies of volunteer growth attach themselves to the rocky 
linings of the tanks, and attain full growth in about six weeks. 
The Star-Spangled Jelly, (Botryllus gouldii). This compound 
ascidian ranges from New Jersey to Maine, and is very abundant 
late in summer upon eel grass. It forms smooth, thick, gelatinous 
expansions of various colors, such as gray-green, dul] yellow, brown, 
purple, or spotted with white. The whole surface appears as if 
