884 
of the brain of the chick has been under- 
taken with the end in view of determining 
the real value of the furrows upon the 
mesal or endymal surface of the brain tube. 
In the earliest stages, while the dorsal union 
is taking place, there is a furrow demarka- 
ting the regica adjacent to the neural crest 
from the remainder of the nervous tube and 
ending in the optic cup. As the neural 
crest separates into ganglia which grow 
down the side of the tube this furrow dis- 
appears and the brain tube assumes the 
well-known moniliform with total folds of 
the wall. 
Of the five transverse furrows of the 
oblongata, two certainly leave a remnant 
which can be traced definitely to the 9th 
and 10th days. To that time there is not 
reestablished a continuous longitudinal fur- 
row throughout the brain tube separating 
the so-called dorsal and ventral zones of 
His, but in each portion of the brain arise 
furrows of limited extent which from com- 
parison with other brains promise to prove 
of value in homologizing parts. 
Further Notes on the Brook Lamprey. (Lam- 
petra wilderi.) Stwon H. Gaaz, Ithaca, 
INR YS 
In this paper were brought out the addi- 
tional facts bearing upon the non-parasitic 
habits of the adult brook lamprey. 
1. It was shown that the lake lamprey, as 
soon as completely transformed, attacked 
fish with great ferocity. 
2. Transformed brook lampreys under 
the same conditions never attacked the fish. 
3. The alimentary canal of the lake lam- 
prey was comparatively large with many 
secondary, longitudinal folds at the time of 
transformation, while that of the brook 
lamprey was very small and quite or almost 
completely unfolded. 
Bearing upon the question of possible 
ancestral parasitism in the brook lamprey, 
serial sections were made of the larvee at 
SCIENCE. 
[N. S. Von. X. No. 259. 
the beginning of transformation, when the 
transformation was nearly complete and of 
the adult at the spawning season. It was 
found: 
1. That the branchial apparatus under- 
goes the same modification as in the lake 
lamprey in that the common branchial 
chamber becomes divided into seven branch- 
ial pouches on each side, and the formation 
of a common median branchial canal open- 
ing into the mouth and by passages into 
each branchial pouch. 
2. That there is developed an esophagus 
connecting the 1. >uth with the alimentary 
canal as in the known parasitic forms (lake 
and sea lamprey ). 
4. The buccal and lingual armature of 
horny teeth is well developed. 
It was concluded that the indications all 
point to an almost certain conclusion that 
the progenitors of the brook lamprey were 
true parasites although at present the 
brook lamprey possesses the esophagus 
which is not used for swallowing food. and 
buccal and lingual teeth which are no 
longer used for lacerating prey, but remain 
as stigmata of an ancestral mode of life. 
Respiration in Tadpoles of the Toad. S. H. 
GaaeE, Ithaca, N. Y. 
On comparing the behavior of toad tad- 
poles with that of the tadpole of the bull- 
frog, for example, one is surprised to find 
that the toad tadpoles go to the surface 
with far less frequency, and if the water is 
very fresh they may appear not to go to the 
surface at all. In a small glass vial they 
may remain at the bottom for half an hour 
or more. An investigation of the develop- 
ment of the lungs showed that they appear 
very early, that is long before the hind legs, 
but it was found that the opening of the 
trachea into the mouth through the glottis, 
and the development of the larynx did not 
occur until the tail was nearly absorbed. 
From this structural condition there could 
