662 THE AMERICAN NATURALIST. 
that the plan would react in any disadvantageous way on the authors. 
The preparation of restricted abstracts, such as this plan requires, is 
at least an exercise in concise composition. 
The Introduction of Exotic Animals. — The Yearbook of the U. S. 
Department of Agriculture for 1898 contains a most important and 
interesting paper by Mr. T. S. Palmer, entitled “ The Danger of 
Introducing Noxious Animals and Birds.” Though Mr. Palmer uses 
animals and mammals as synonymous terms, his subject would bear 
more extended treatment. The need of legislation to prevent the 
importation of species which may become injurious is well and 
temperately stated ; scientific men, however, should unite in preserv- 
ing the integrity of the natural faunas and floras, and should urge 
that all laws made to forbid the introduction of exotic species include 
Mongolian pheasants introduced for sport, and skylarks brought here 
for the charm of their song. 
Colors of Deep-Sea Animals. — In a paper of this title (Rept. 
Towa Acad. Sci., 1898) Dr. C. C. Nutting explains the occurrence of 
bright pigments and well-developed eyes in animals from great depths 
by the existence there of a phosphorescent light emanating from the 
animals themselves, and in support of his idea advances the fact that 
cave animals, on the other hand, are colorless and blind. We wish 
to point out that Dr. Walter Faxon in his report on the Stalk-Eyed 
Crustacea of the Albatross expedition (Mem. Mus. Comp. Zobi., Vol. 
XVIII, 1895) devotes a special chapter to the colors of deep-sea 
_ Crustacea, and suggests the existence at great depths of a phosphor- 
escent light; and he also emphasizes the opposite conditions existing 
in cave animals. The prevailing red tints of deep-sea forms are 
explained by Faxon through simple physiological reactions in the 
chromatophores owing to the absence of bright light, and in support 
of his theory cites some of the experiments of Pouchet on shore 
forms. 
