1885.] Zoology. 613 
side only, was placed in the labyrinthine aquarium. It contrived 
to keep the non-mutilated side turned towards any obstacle. 
These experiments leave no doubt as to the function of the 
lateral line. It is a very delicate organ of touch, adapted to the 
requirements of an aquatic life. It is sensitive to the faintest 
movement of the water, takes cognizance of the slightest displace- 
ments, and gives fishes continual information on the state of the 
medium in which they live. 
ZooLocicaL News.— Vermes.—Mr. W. Bateson has contributed 
to the Quart. Jour. Micros. Sci., an account of the early stages of 
the development of examples of Balanoglossus found at Hampton, 
Va. The adults agree very closely with B. kowalevskii of Agassiz, 
but as the development differs, the species cannot be identified. 
At no stage has the larva any superficial resemblance whatever to 
a Tornaria, such as is described by Agassiz as occurring in the 
development of B. kowalevskii. The eggsare elliptical and opaque, 
are fertilized outside of the body ; divide into two, segment regu- 
larly and then form a hollow blastophore, enclosing a segmen- 
tation cavity. The gastrula is formed by invagination, the blasto- 
pore closes completely, a posterior transverse ring of cilia, forms, 
and the body elongates and becomes marked out into regions. 
The mouth is a small pore in the ventral middle line of the ante- 
rior transverse groove; and the nervous system is formed by a 
segregation of epiblastic cells in the dorsal middle line of the 
collar, forming a cord lying immediately beneath the skin. The 
larva is always opaque, and creeps about in the muddy sand when 
hatched. 
Celenterates—According to R. von Lendenfeld, the Crambessa 
mosaica in Port Jackson is brown, while that of Port Philip is 
deep blue. The difference is caused by the presence of Zoanthel- 
læ, parasitic algae which may possibly be young stages of Lami- 
Narians, in the Sydney variety, which Mr. Lendenfeld names 
Crambessa mosaica symbiotica, because it has become associated 
symbiotically with an alga, and thus differs from the Melbourne 
form as lichens differ from fungi. Should the variety not be able 
to live without its parasite, it would be a new species. Huxley, 
in 1845, does not notice the brown color, and all previous au- 
thors, though they have collected the species near Sydney, de- 
scribe it as varying in color from blue to gray. . Our author asks 
whether the change has taken place since 1845 ? 
Batrachians and Reptiles —Professor E. D. Cope as one of the 
results of his studies on the batrachian and reptilian fauna of 
Mexico and Central America, which had been prosecuted by the 
use of material mainly placed at his disposal by the Smithsonian 
Institution, states that the total number of species described up 
to date is six hundred and ten, which is described as follows : 
VOL, XIX.—NO. VI. 40 
