726 Scientific News. [ November, 
“Such a hypothesis as that nature had either all her birds or all 
her mammals from one stock is at once upset by the facts pre- 
sented by the structure of the lowest mammals, the duck-billed 
Platypus and the Echidna. Between the mammals and the types 
which foreshadow them, viz: the Selachians and the Batrachians, 
there is unfortunately a large chasm , and, moreover, the Platypus 
and Echidna refuse to lie fairly in the direction indicated at the 
top of this chasm, or they confusingly partake of the characters 
of the reptile and bird; as well as those which are peculiarly 
mammalian * * * as already mentioned, the forecast of the 
mammalian type, which is very plain in the cartilaginous fishes, 
becomes much more plain, definite and indubitable in the frog 
and toad. In fact, the building materials are passed from hand 
to hand, as it were, in this way: the batrachian forefathers brought 
down all things meet for the work, borrowing and taking carti- 
lages from the Selachians and bones from the Ganoids, and noise- 
lessly forming them, after due selection, into a new, more com- 
pounded and noble structure. The rude ancestors of the tribes 
that give suck began to build on this higher level ‘ until the con- 
summation was effected of vertebrate form.’ But the consumma- 
tion of all, the election and selection that has been going on since 
the beginning of the ages, is seen in man, who alone gives mean- 
ing to, and reads the meaning of, the whole mystery of organic 
He.” 
— From his recent studies on the habits of the cotton-worm 
moth, Prof. C. V. Riley concludes, in a paper lately read before 
the National Academy of Sciences, that the species is not repre- 
sented by the egg, larva or chrysalis in the winter, but that the 
moth hibernates. His paper ends as follows: “ My own belief 
now is that the moth really survives the winter in the more 
southern portions of the cotton belt, as on the Sea islands of 
Georgia and in parts of Florida and Texas, and that it 1s from 
this more southern portion that it spreads this year. 
“ This belief, which yet lacks full confirmation, does not pre- 
clude the occasional coming of the moth from foreign, more 
tropical countries, or the possibility of its being brought by favor- 
able winds from such exterior regions; though the fact is estab- 
lished that it could not have come from the Bahamas since 1866. 
“The question has an important practical bearing, for, on the 
theory of the insect’s ability to remain with us, much important 
fall and winter work of a preventive nature may be done 1n 
destroying the moths; whereas on the theory of its annual per- 
ishing and necessarilly coming from foreign countries, no such pre- 
_ ventive measures are left to the planter. The time employed in 
baiting and destroying the last brood of moths in autumn will he. 
-~ wasted, and he must helplessly await the coming of the parent ae 
the ensuing spring, and deal as best he can with the progeny. —— 
